Precipitated silicas for storage-stable rtv-1 silicone rubber formulations without stabilizer

[0001] The present invention relates to precipitated silicas that allow the preparation of storage stable RTV-1 silicone rubber preparations without a stabilizer, a method for their production and their use for thickening sealing masses.

[0002] By sealing compounds is meant flexible materials applied in the form of a liquid or viscous material for sealing buildings or equipment against water, atmospheric influence or aggressive means.

[0003] Silicone rubbers are those transformed into a state of elastic gum that contain polydiorganosiloxanes as basic polymers that have groups available for cross-linking reactions. As such, H atoms, OH groups and vinyl groups that are at the ends of the chains are taken into account, but they can also be incorporated in the chain. In this system fillers are included as amplifiers, the type and quantity of which significantly affect the mechanical and chemical behavior of vulcanizates. Silicone rubbers can be dyed with inorganic pigments. A distinction is made between hot vulcanizing and cold vulcanizing rubber (high / room temperature vulcanizing = HTV / RTV).

[0004] Cold-curing masses of RTV silicone rubbers are distinguished by one-component systems and two-component systems. The first group (RTV-1K) polymerizes slowly at room temperature under the influence of atmospheric humidity, cross-linking by condensation of SiOH groups to form Si, O bonds. The SiOH groups are formed by hydrolysis of SiX groups formed directly from the polymer with terminal OH groups and thus called the R-SiX3 cross-linking substance (from B. X = -O-COCH3, -NHR) species. For bicomponent rubbers (RTV-2K), for example, mixtures of silicic acid esters (e.g., ethyl silicate) and organic tin compounds are used as cross-linking substances, with cross-linking being the cross-linking reaction

Si-O-Si with Si-OR and Si-OH (- = methyl group; R = organic residue) by cleaving the alcohol.

[0005] For thickening RTV-1K silicone rubber, among others, silicas. These can contribute to the system due to the sensitivity to the hydrolysis of sealing silicone masses with as little moisture as possible. So far, almost exclusively pyrogenic silicas have been used for this application. The hydrophilic precipitated silicas could not be used up to now due to their high moisture content.

[0006] WO 2005/061384 discloses the manufacture and use of, among others in silicone rubber, precipitated silicas, which should have, according to the claim, a water absorption of <6% and DOP> 300 ml / 100 g. Published in the examples WO

- 2005/061384, the precipitated silicas have, however, all together a water absorption between 5.7 and 5.9% and are therefore not suitable for the aforementioned reasons for use in RTV-1K formulations. Consequently, in WO 2005/061384 only the use in silicone rubber preparations for the extrusion process (HTV) is described.

[0007] EP 1557446 only describes preparations of HTV silicone rubber. The silicas used there have a loss on drying of <4%. The preparations published in EP 15 155 746 are used for the production of insulating materials such as, for example, cable sheeting.

[0008] From DE 102005005046, precipitated silicas are known which have a silanol group density of less than 2.5 SiOH / nm² and they are silylated on the surface.

[0009] Further from EP 1561727 are known alkaline precipitated silicon cysts with a pH value>

8.

[0010] In summary, it can therefore be concluded that in the prior art, no precipitated silicas have been published that meet the high requirements for use in RTV-1K silicone rubber. There is therefore a high demand for such usable RTV-1K precipitated silicas.

[0011] To solve the aforementioned problem, DE 102006024591 and DE102006024590 have been proposed for precipitated silicas which are suitable for RTV-1K silicone rubber preparations. However, the drawback of the precipitated silicas published there is that a stabilizer and relatively large amounts of cross-linking substance must be added to achieve a good storage stability of the RTV-1K preparations.

[0012] Starting from the above-described prior art, the object of the invention was to provide precipitated silicas at which the previously outlined defects of the precipitated silicas of the prior art would be removed completely or at least in part. In addition, a method for preparing the precipitated silicas of the invention should be provided.

[0013] Further non-specific tasks result from the combined context of the description, examples and claims.

[0014] Surprisingly, it has been found that this task can be solved by the silicic acids according to the invention described in more detail in the following description as well as in the claims and examples.

The present invention therefore relates to precipitated silicas having an extinction ratio SiOHisolated greater than or equal to 1.5, a density of silanol groups of 1 to 3.0 SiOH / nm² and a modified compacting density of 1 to 50 g / l, and are characterized in that the pH of the precipitated silicic acid is in the range of 3-5, in addition to the precipitated silicic acid having a pH value of 4-5.

[0016] The present invention also relates to precipitated silicas, preferably hydrophilic precipitated silicas, which in addition to the aforementioned parameters,

- 3 independently of one another, have one or more of the following physicochemical parameters:

- BET area 50 - 600 m²/ g - surface CTAB 50 - 350 m²/ g - DBP (dehydrated) 150 - 400 g / 100g - loss at roasting 0.1 - 3.0% by weight - loss on drying 0.1 - 3.0% by weight

- a fraction of 5 to 100% of fine particles <1 μm in the distribution of molecules depending on the volume

- d value₉₀ from 0.001 to 10 μm particle size distribution.

[0017] A further object of the invention is a process for the preparation of precipitated silicas of the invention as defined in the claims and the following description.

[0018] A further object of the invention is the use of the precipitated silicas of the invention in sealing compounds, in particular in silicone rubber or sealing silicone masses, and particularly preferably in RTV-1K sealing compounds. It is possible to use in various crosslinking systems, e.g. acetoxy-crosslinking, alkoxy-crosslinking and oxime-crosslinking systems. These systems are used, for example, in the construction industry as sealing compounds for joints, in the automotive industry as adhesive and sealing material and as coating compounds for textile fabrics.

[0019] A further object of the invention is silicone rubber sealing masses that contain the precipitated silicas of the invention and their use.

The precipitated silicas of the invention have the advantage, due to their special structure and surface properties, that they guarantee, after treatment in silicone rubber masses, in particular RTV-1K type, high storage stability, high durability and optimal silicone rubber yield strength, although the silicone rubber formulation does not contain a stabilizer.

[0021] The inventors have surprisingly found that the precipitated silicas with an extinction ratio SiOHisolated greater than or equal to 1.5, densities of silanol groups from 1 to 3.0 SiOH / nm² and a modified dough density of 1 to 50 g / l, when they have a pH in the range of 3-5, in addition to the precipitated silicic acid with a pH value of 4-5 ensure good storage stability of silicone rubber preparations without adding a stabilizer.

[0022] The further precipitated silicas of the invention have the advantage that by the special combination of parameters claimed in claim 1 the necessary amount of cross-linking substance in the RTV-1K silicone rubber preparations can be clearly reduced, resulting in a significant economic benefit.

[0023] Despite the resignation of the stabilizer and the reduction of the amount of cross-linking substance,

- 4 RTV-1K preparations containing the precipitated silicas of the invention have a high thixotropy. In addition, the precipitated silicas of the invention can be subjected to a good and rapid dispersion in silicone rubber preparations and thus a high thickening effect is achieved in the silicone rubbers RTV-1K.

[0024] Thus, the precipitated silicas of the invention offer essentially cost savings as previously used in the RTV1 silicone rubber, because they can be cheaper to produce.

[0025] The objects of the invention will then be described in detail.

[0026] In this invention, the terms silicic acid and precipitated silicic acid are used synonymously. Hydrophilic precipitated silicas are understood to mean those whose surface, when reconstituted with water, behave hydrophilically, i.e. their surface is completely cross-linked with water and thus has a contact angle on the water which is less than 90 °. He he he T4 T4 T T4 T4 T T4 T4 T T4G4GG T T4G4 T T4 TG T T44 T T4 T4 T4 T T4 T T he T4 T 00 T he TG T T he he T T T4 T4 T4 T T4G T4 T4 T4 T T T heG T T T T4 TG TG he TG he T T he T T

[0027] The precipitated silicas of the invention are distinguished in that they have a particularly high proportion of isolated SiOH groups, expressed by the SiOHisolated extinction ratio, on their surface. The extinction ratio of SiOHisolated precipitated silicas of the invention is greater than or equal to 1.5, preferably between

1.5 and 10, particularly preferably between 1.5 and 7, particularly very preferably between

1.8 and 5, particularly preferably between 2 and 4.5, particularly particularly preferably between 2.3 and 4.0 and particularly preferably between 2.3 and 3.5. This particular property of the surface of the precipitated silicas of the invention is an important property that leads to the fact that the precipitated silicas in the silicone rubber preparations lead to high storage stability, for better stability and for optimum flow behavior.

[0028] The precipitated silicas of the invention are further distinguished by the low density of silanol groups, i.e. the wide spacing of silanol groups on the surface of the precipitated silicic acid. The amount of silanol groups on the surface of the precipitated silicic acid is then determined by LiAlH4 to determine the density of silanol groups. This alone is not convincing, however, because the high surface silicates precipitated usually have a high absolute number of silanol groups as precipitated silicas with a low surface area. Therefore, the number of silanol groups should be related to the surface of the precipitated silicic acid. As a suitable surface, here the BET surface appears, because this describes a surface that is also available for smaller molecules such as water.²preferably from 1.0 to 2.8 SiOH / nm²particularly preferably from 1.5 to 2.8 SiOH / nm². If the number of silanol groups per nm²It is too low, it can cause a low flow limit and thus negatively affect the durability of silicone sealing compounds.

[0029] The precipitated silicas of the invention further have a low modified density after whipping. At the same time, it should be noted that by the modified density after whipping

- 5 is the density after whipping, measured on the uncompressed material. In order to be able to determine this quantity also on pre-compacted packaging and storage materials, sample preparation should be performed as described in the paragraph "Determining the modified density after whipping". The precipitated silicas of the invention may preferably have a modified density after whipping from 1 to 50 g / l, particularly preferably from 5 to 55 g / l, particularly very preferably from 10 to 50 g / l and especially preferably from 10 to 30 g / l.

[0030] Finally, the precipitated silicas of the invention are distinguished by a pH value in the range of 3-5, in addition to the precipitated silicic acid having a pH value of 4-5. The low pH value allows the stabilizer to be dispensed with the preparation of silicone rubber preparations and thus also without storage stabilizer good storage stability.

[0031] Without referring to the special theory, the special properties of the precipitated silicas of the invention mean that they allow the production of stable silicone rubber preparations with excellent properties for industrial use, such as good durability and rheology, without the addition of a stabilizer, Explain by the high number of isolated SiOH groups precipitated silicas in combination with their large spacing, low modified by the densification density and above all low pH value. In addition, by means of a special combination of the physico-chemical properties of the precipitated silicas of the invention it can be achieved that only silicas of the cross-linking substance for the formulation are required when using the silicas of the invention as a filler in silicone rubber preparations.

[0032] The BET surface area describes the effect of precipitated silicic acid on the behavior when treated in silicone rubber as well as the properties of crude mixtures (cf. S. Brunauer, PH Emmett, E. Teller, "Adsorption of Gases in Multimolecular Layers", J. Am. Chem. Soc. 60, 309 (1938)). Thus, the precipitated silicas of the invention may have a BET surface area of ​​50 to 600 m²/ g, preferably 50 to 400 m²/ g, particularly preferably 50 to 250 m²/ g, particularly very preferably from 80 to 230 m²/ g, particularly preferably from 100 to 180 m²/ g, very particularly preferably from 125 to 180 m²/ g and especially preferably from 140 to 170 m²/ G.

[0033] The surface area of ​​CTAB is predominantly critical for the reinforcing property of the precipitated silicic acid (cf. Janzen, Kraus, Rubber Chem. Technol. 44, 1287 (1971)). The strengthening potential increases with the increasing area of ​​CTAB. Thus, the precipitated silicas of the invention may have a CTAB surface area of ​​50 to 350 m²/ g, particularly preferably 50 to 250 m²/ g, particularly very preferably from 80 to 230 m²/ g, particularly preferably from 100 to 200 m²/ g, very particularly preferably from 125 to 190 m²/ G.

[0034] In addition, it has been found that the high DBP absorption of the precipitated silicas of the invention can be used to achieve good rheological properties on silicone rubber preparations. However, too high DBP values ​​can lead to an excessive increase in the viscosity of the silicone rubber and should therefore be

- 6 avoided. The precipitated silicas of the invention may therefore preferably have a DBP absorption of 150 to 400 g / (100 g), particularly preferably 200 to 350 g / (100 g), particularly very preferably 220 to 330 g / (100 g), particularly preferably 250 to 330 g / (100 g), very particularly preferably 260 to 320 g / (100 g).

[0035] The inventors have further found that a particular advantage for the durability of silicone sealing compounds can be when the precipitated silicas of the invention have a sufficient proportion of fine particles, i.e. particles <1 μm. This applies to all previously described embodiments. Thus, the precipitated silicas of the invention have in the particle size range <1 μm of the volume-dependent distribution of particles preferably a proportion of fine particles from 30 to 100%, more preferably 30 to 95%, particularly preferably 35 to 95%, quite particularly preferably 35 to 90%, preferably 40 to 90%, particularly preferably 45 to 80% and particularly preferably 50 to 80%.

[0036] It has also been found that too high a proportion of large molecules can adversely affect the industrial application properties of the precipitated silicas of the invention. Thus, the precipitated silicas of the invention are distinguished by the fact that with respect to the volume-dependent distribution curve of the d-values₉₀ between 0.001 and 10 μm, preferably between 1 and 10 μm, particularly preferably between 2 and 8 μm and particularly preferably between 3 and 7 μm.

[0037] The particle distributions may be monomodal or bimodal, preferably bimodal.

[0038] It has also been found that for all of the previously described embodiments of the precipitated silicas of the invention it may be particularly advantageous if the precipitated silicas bring up as little moisture as possible to the silicone sealant. The precipitated silicas of the invention may therefore have an initial moisture, expressed as loss on drying, of from 0.1 to 3.0% by weight, preferably from 0.2 to 2.5% by weight, particularly preferably from 0.3 to 2.0% by weight. and especially preferably 0.4 to 1.8% by weight and / or loss on ignition from 0.1 to 3.0% by weight, preferably 0.2 to 3.0% by weight, particularly preferably 0.3 to 2.0% by weight by weight and particularly preferably 0.4 to 1.8% by weight.

[0039] Said preferred ranges can be set independently of one another.

[0040] The precipitated silicas of the invention can be prepared according to a method that includes the following described steps;

1. a reaction of at least one silicate and at least one acidifying agent

2. filtration and rinsing of the precipitated silicic acid obtained

3. drying the resulting precipitated silicic acid or filter cake

4. optionally grinding the precipitated silicic acid obtained according to step 3

5. tempering of the dried and / or milled precipitated silicic acid

6. optionally grinding the precipitated silicic acid obtained according to step 5

And - characterized in that after step 3 and / or 4 and / or step 5 and / or step 6 an acidifying agent of at least one type is added and the precipitated silicic acid obtained at the end of the method has a pH value of 3-5, in addition to precipitated silicic acid with a pH value of 4-5.

Stage 1 preferably comprises partial steps. [0041] 1a: Preparation of a receptacle from water or water and at least one silicate and / or silicate solution, the pH of the recipient thus obtained being preferably between pH 5 and pH 10 and the temperature of the receptacle preferably between 80 and 100 ° C.

[0042] 1b: Dosing of at least one silicate and / or silicate solution and at least one acidulant during mixing at 80 to 100 ° C in the receiver from the partial stage 1a), so long as the solids content of the precipitation suspension is reached, which it leads to the solid content reached in partial stage 1c). Here, the addition of silicate and / or silicate solution and acidifying agent takes place particularly preferably simultaneously and / or so that the pH value is maintained during the duration of the partial step 1b) continuously at a value between pH 7 and pH 10.

[0043] 1c: Addition of an acidifying agent at a temperature of the precipitating slurry from 80 to 100 ° C such that the pH of the precipitating slurry decreases from 2 to 6 and the solids content of the precipitating slurry is at the end of the partial stage between 30 g / l.

[0044] Preferably, the precipitated silicas of the invention have been prepared. This is particularly advantageous in that the silicas of the invention are in step 4, i.e. between steps 3 and 5 or in step 6, i.e. after step 5, or both in step 4, i.e. between step 3 and 5, as also in phase 6, i.e. after step 5.

[0045] All known silicate forms are considered for the silicate or silicate solutions used in step 1) of the method according to the invention. Preferably, the silicates used according to the invention are alkali silicates, e.g. sodium or potassium silicates. It is particularly preferably at step 1 for sodium silicate (water glass). Its mass ratio SiO2 to Na2O is between 2 and 4, preferably between 3 and 3.6 and particularly preferably between 3.3 and 3.5. The SiO 2 content is preferably between 20 and 40% by weight, preferably between 25 and 30% by weight.

[0046] By acidifying agents are meant acidic compounds of organic or inorganic nature by means of which the pH of the precipitation suspension can be lowered. Inorganic acids such as hydrochloric acid, phosphoric acid, sulfuric acid or nitric acid or organic acids such as acetic acid, formic acid or carbonic acid or carbon dioxide may be used advantageously. Both dilute as well as concentrated acids can be used. The sulfuric acid is particularly preferably used in the process according to the invention.

[0047] Most commonly used in the partial stages 1a) to 1c) silicate and / or solution

- 8 silicate and acidifying agent are identical.

[0048] The pH of the receiver in the partial stage 1a) is preferably between pH 7 and pH 10, particularly preferably between pH 8 and pH 9. The temperature of the receptacle is set at 80 to 100 ° C, preferably at 85 to 95 ° C.

In the partial stage 1b), the silicate and acidifier are preferably metered simultaneously. The addition of the two components is preferably always constant throughout the duration of the partial step 1b). The temperature remains during them at 80 to 100 ° C, preferably 85 to 95 °. The duration of the addition lasts until the solid content reached at the end of step 1c) is reached. In this case, it may be necessary for the precipitation to continue through the point of viscosity increase. This point of increase in viscosity corresponds to the time point at which the viscosity of the precipitating slurry in the course of precipitation is observed, cf. EP 0643015. During the partial stage 1b) in which the precipitation of silicic acid starts, the pH is kept as constant as possible at a pH between pH 7 and pH 10,

[0050] By adding an acidulent agent at the temperature of the precipitating slurry from 80 to 100 ° C, the pH is reduced at 2 to 6, preferably at pH 3 to 6, particularly preferably at pH 3 to pH 4, in a partial step 1c). the solid precipitating slurry is at the end of this partial stage between 30 and 70 g / l, preferably between 45 and 60 g / l and very particularly preferably between 45 and 55 g / l.

[0051] Without referring in any way to a particular theory in step 1b), a chain structure of aggregates is created by appropriate selection of the process parameters. Due to a sufficiently slow further precipitation also after the point of viscosity growth, the reinforcement of this really loose structure of the aggregate is achieved.

[0052] The dosing rates in step 1b) are selected in all the embodiments of the process according to the invention both before and after the viscosity increase point such that after acidification in step 1c) a target solids content of 70 ai g / l is reached.

Filtration, condensation (e.g. according to DE 2447613) and long-term and short-term drying of the precipitated silicas of the invention are known to the person skilled in the art and can be read, e.g. in the documents mentioned herein. The filtration and washing of the precipitated silicic acid is preferably carried out in such a way that the conductivity of the final product is <1000 μs / cm, preferably <500 μs / cm and particularly preferably <200 μs / cm.

[0054] The precipitated silicic acid of the invention is preferably dried in a pneumatic dryer, spray dryer, tray dryer, belt dryer, rotary dryer, jet dryer, jet dryer or band dryer.

- 9 with nozzle blowing of the drying gas. The drying variants given here include the use of a drive with a sprayer, a single or spray nozzle and an integrated fluidized bed. Spray drying can be carried out, e.g., according to US 4094771.

[0055] If spray drying has been chosen as the drying process, which is particularly advantageous, the filter cake must be re-dispersible beforehand. The re-dispersion is preferably carried out in water or an aqueous acid, so that the suspension has a pH of from 4 to 7. In this regard, care should be taken that the suspension of precipitated silicic acid after re-dispersion has a solid content of 5 to 18, preferably 8 to 13 % by weight, particularly preferably 9 to 11% and that during re-dispersion the precipitated silicic acid does not interact too strongly with shear forces. This can be achieved e.g. by stirring at a rotational speed of <1000 U / min, preferably being mixed covering the entire space, and not pointwise.

[0056] The milling of the precipitated silicas of the invention can be carried out, e.g. as described in Ullmann, 5th edition, B2, 5-20. The grinding of the precipitated silicas according to the invention preferably takes place in step 4 and / or in step 6, particularly very preferably in step 4. Particularly preferably, a grinding system (grinding apparatus) comprising or consisting of impact mills or jet mills is used, preferably from anti-collision mills. Fluidized bed jet mills are particularly preferably used. Particularly very preferably grinding takes place by means of a grinding system (grinding apparatus), especially preferably a grinding system including a jet mill, characterized in that the mill of the grinding system in the grinding phase is driven by the driving means selected from the group,

Particularly preferably, the milling is carried out according to the method described in DE 10 2006 048 850.4 by means of the grinding system (mill) described therein, particularly preferably steam is used as the propellant. To avoid pure repetition of the text, the content of the cited patent letter is included in detail in the content of this application. The grinding parameters are preferably selected such that the milled product has a range of less than 1 μm depending on the volume of particle distribution of fine particles from 5 to 100%, preferably 10 to 95%, particularly preferably 15 to 95%, particularly very preferably 20 to 90. % and particularly preferably from 40 to 80% and / or the d90 value of the volume-dependent particle distribution curve between 0.001 and 10μm.

[0058] In an extremely advantageous embodiment, an anti-condensation mill is heated to prepare the proper grinding by means of hot steam.

A fluidized bed according to FIG. 1 with an integrated dynamic air separator according to FIGS. 2 and 2a followed by two heating nozzles (5a) (of which only one is shown in FIG. 1) which are driven by hot compressed air, preferably at 10 bar and 160 ° C, up to the exit temperature of the mill, which is more than the dew point of steam and / or propellant, preferably around 105 ° C.

[0059] A filtering device (not shown in figure 1) is attached to the mill for separating the ground material, the filter body of which is lower in the third third heated just the same by the heat shocked by means of saturated steam, preferably saturated steam (pressure 6 bar) ) to avoid condensation. All surfaces of the device within the mill, separating filter and supply lines for steam and hot compressed air are particularly insulated.

[0060] Once the desired heating temperature has been reached, the heating nozzles with hot compressed air are switched off and the three grinding nozzles are driven with heated steam, preferably 38 bar (abs) at 325 ° C.

[0061] To protect the filter medium used in the separating filter and to set a specific content of residual water of the milled material of preferably 2 to 6%, the water in the starting phase and during grinding in the grinding space of the mill is fed with a compressed air-driven spray nozzle depending on the temperature outlet mill.

[0062] The amount administered is regulated depending on the settling stream of the separator. The separator stream regulates the amount fed in such a way that approximately 70% of the rated flux can not be exceeded.

[0063] In this case, as an introducer (4), there was a drum with adjustable volume dividers, dispensing the feed material from the feed tank to the overpressure grinding chamber through a bar impulse lock serving as a barometric closure.

[0064] The grinding of coarse material took place in expanding steam streams (grinding gas). Together with the relaxed grinding gas, the product particles in the middle of the mill tank rise to the separator rotor. Depending on the rotational speed of the separator and the amount of grinding steam, particles with sufficient fineness get in with the grinding steam to the fines outlet and from there to the separating system connected further, while the too coarse particles get back into the grinding zone and are subjected to secondary grinding. The output of the separated fines from the separating filter to the following silo and packing takes place via a lock with a baffle drum.

[0065] The grinding pressure of the grinding gas prevailing at the grinding nozzles or the resulting amount of grinding gas in connection with the speed of rotation of the dynamic air separator with the scoop wheel determine the fragmentation of the grain size distribution function and the upper grain boundary.

[0066] In a preferred embodiment, the method according to the invention runs in

- a grinding system (grinding apparatus), preferably in a grinding system including a jet mill, particularly preferably including an anti-condensation mill. The crushed material is accelerated in the expanded high-velocity gas streams and disintegrated by particle-particle collisions. As stream mills, it is particularly advantageous to use fluidized bed jet mills or fluidized jet mills with compact or spiral jet mills. In the case of a particularly advantageous fluidized bed jet mill, in one third of the lower part of the milling chamber there are two or more grinding mill inlets, preferably in the form of grinding nozzles, which are particularly in the horizontal plane. The grinding milling inlets are arranged particularly preferably around the circumference of the preferably round mill tank, so that the grinding radii meet all at one point of the grinding tank. Especially preferably, the grinding radial inlets are evenly distributed around the circumference of the grinding tank. In the case of three grinding-mill inlets, the distance would therefore each be 120 °.

[0067] In an exemplary embodiment of the method according to the invention, the grinding system (grinding apparatus) comprises a separator, preferably a dynamic separator, particularly preferably a dynamic separator with a scoop, in particular a separator according to figures 2 and 3.

[0068] In another preferred embodiment, the dynamic air separator according to figure 2a and 3a is used. This dynamic air separator comprises a separator rotor and a separator shaft and a separator body, wherein a separator gap is formed between the separator rotor and the separator body and between the separator shaft shaft and the separator shaft body and is characterized in that the separator slot purge and / or carrying out the shaft takes place with compressed low-energy gases.

[0069] By using a separator in combination with the jet mill actuated in the conditions of the invention, the upper grain is limited, the product particles rising with the expanded gas streams are guided from the center of the grinding tank through the separator and finally the product which has sufficient fineness is discharged from the separator and from the mill. The coarse particles get back into the grinding zone and undergo further crumbling.

[0070] In the grinding system, the separator can be included as a separate mill unit, but preferably an integrated separator is used.

In a particularly advantageous milling process, before the actual milling step, a heating phase is activated, in which the grinding chamber is guaranteed, particularly preferably all relevant building elements of the mill and / or grinding system on which water and / or water vapor can condense. it is heated in such a way that its temperature is above the dew point of the steam. The heating can take place essentially by any heating method. Preferably, however, the heating occurs because the hot gas is passed through the mill and / or the entire grinding system such that the temperature of the gas at the outlet of the mill is higher than the dew point of the steam. It is considered as such

It is particularly advantageous for the hot gas to sufficiently heat all of the essential building blocks of the mill and / or the entire grinding system that are associated with the steam.

[0072] As any heating gas, any gas and / or gas mixture may be used, however, hot air and / or combustion gases and / or inert gases are preferably used. The temperature of the hot gas is above the dew point of the steam.

[0073] The hot gas can be essentially arbitrarily introduced into the grinding chamber. Preferably, there are inlets or nozzles in the grinding chamber for this purpose. At the inlets or nozzles may be the same inlets or nozzles through which grinding radii (grinding nozzles) are also carried out during the grinding phase. It is also possible that separate inlets or nozzles (heating nozzles) are present in the grinding space, through which hot gas and / or a gas mixture can be introduced. In a preferred embodiment, the heating gas or the heating gas mixture is introduced by at least two, preferably three or more inlets or nozzles located in the plane, which are arranged circumferentially in a preferably circular mill tank so that the rays meet all at one point inside the grinding tank .

[0074] During grinding by grinding slots, preferably in the form of grinding nozzles, a gas and / or steam, preferably steam and / or a gas / steam mixture, is expelled as a propellant gas. The driving means generally have a significantly higher acoustic velocity than air (343 m / s), preferably at least 450 m / s. Preferably, the driving means comprise water vapor and / or hydrogen gas and / or argon and / or helium. It is particularly preferably heated in steam. In order to achieve very fine grinding, it has proven particularly advantageous to pressurize the driving means in the mill with a pressure of 15 to 250 bar, particularly preferably 20 to 150 bar, particularly very preferably 30 to 70 bar and especially preferably 40 to 65 bar. In the same way, the propellant is particularly preferably at a temperature of 200 ° C to 800 ° C,

[0075] In the case of water vapor as the driving means, i.e. especially when the steam supply line is connected to the steam source, it is particularly advantageous to connect the grinding or inlet nozzles to the steam supply line equipped with expansion arches.

[0076] It has also been found advantageous if the jet mill surface has the lowest possible value and / or the flow paths are at least mostly free of protrusions and / or when the jet mill components are planned to avoid bulk accumulation. The milling of the ground material can additionally be prevented by these steps.

[0077] On the basis of the preferred and exceptional embodiments of the method according to the invention as well as the preferred and particularly suitable embodiments of jet mills as well as figures and descriptions of the figures, the invention is only explained in more detail, i.e. it is not limited to these examples.

- execution and application or to a respective combination of features within particular embodiments.

[0078] The particular features, given and / or presented in the context of specific embodiments, are not limited to these embodiments or combinations with the remaining features of these embodiments, but can be combined in technical capabilities with all other variants, including if in these documents have not been treated separately.

[0079] The same reference numerals in the individual figures and illustrations of the drawings mean the same or similar or the same or similarly functioning components. On the basis of the graphs in the figure, features without reference numerals are clearly visible, regardless of whether such features are described or not. On the other hand, for the specialist, there are undoubtedly also understandable features, included in this description, but invisible or not shown in the drawing.

[0080] As already mentioned above, in the method according to the invention, a jet mill, preferably an anti-condensation mill, with an integrated air separator, preferably with an integrated dynamic air separator, can be used to produce the finest particles. Particularly preferably, the air separator comprises a separator rotor and a separator shaft and a separator body, wherein a separation gap is formed between the separator rotor and the separator body and between the separator shaft and the shaft seal housing and the separator is operated so that the separator gap / or the shaft penetration takes place with compressed low-energy gases.

Preferably, a scrubbing gas having a pressure of not less than at least about 0.4 bar, particularly preferably no greater than at least about 0.3 bar and especially not more than about 0.2 bar above the internal pressure of the mill is used. . The internal pressure of the mill can be at least in the range of about 0.1 to 0.5 bar.

[0082] It is furthermore advantageous if a scrubbing gas with a temperature of about 80 to about 120 ° C, especially about 100 ° C is used, and / or when compressed air with low energy is used as the scrubbing gas, especially (at pressure) about 0.3 bar to about 0.4 bar.

The rotational speed of the air separator rotor and the internal gain ratio V (= Di / DF) can be adjusted or adjusted so that the peripheral speed of the driving means (B) on the impeller pipe or outlet stub assigned to the rotor reaches up to 0.8. times the acoustic velocity of the driving medium. In formula V (= Di / DF), they mean: Di = the inner diameter of the separator (8), i.e. the distance between the internal edges of the blades (34) and DF = the inner diameter of the diving tube (20). In another preferred embodiment, the inner diameter of the separator is Di = 280 and the inner diameter of the dive tube

DF = 100 mm. For the definition of the gain ratio, see also R. Nied, "Stromungsmechanik und Thermodynamik in der mechanischen Verfahrenstechmk", available in consulting companies Dr. med. Roland Nied, 86486 Bonstetten, Germany.

- 14 Also available from NETZSCH-CONDUX Mahltechnik GmbH, Rodenbacher Chaussee 1, 63457 Hanau, Germany.

This can be further shaped by selecting or setting or adjusting the rotational speed of the rotor of the air separator and the internal gain ratio V (= Di / DF) so that the peripheral speed of the driving means (B) on the dive tube or outlet stub reaches up to 0, 7 times and particularly preferably up to 0.6 times the acoustic velocity of the driving medium.

[0085] In addition, it can be particularly advantageous to provide that the separator rotor exhibits with a decreasing radius an increase in height in the light, wherein preferably the flow area of ​​the separator rotor is at least more or less constant. Alternatively or additionally, it may be advantageous if the separator rotor has an interchangeable rotating dive tube with it. In yet another variant, it is advantageous to provide an outlet chamber of the finely ground material with a cross section increasing in the direction of flow.

[0086] Furthermore, the jet mill according to the invention may advantageously comprise in particular an air separator having individual features or a combination of features of the air separator according to EP 0 472 930 B1. Through this reference, in order to avoid identical acquisition itself, the entire content of disclosure EP 0 472 930 B1 is included herein in its entirety. The air separator can especially comprise means for reducing the peripheral flow components according to EP 0 472 930 B1. In this case, it can especially be provided that the air separator associated with the rotor, developed as a diving pipe, the outlet port preferably has a rounded cross-sectional section to avoid the formation of vortices.

[0087] Preferred and / or useful embodiments of the grinding or milling system used in the method according to the invention result from figures 1 to 3a and the accompanying description, it being further emphasized that these embodiments explain the invention only by way of example only, i.e. it is not limited to these embodiments and uses or the respective combinations of features within the individual embodiments.

Fig. 1 schematically shows an embodiment of a jet mill in a schematic sketch in partial section.

Fig. 2 shows an embodiment of an air jet separator in a vertical arrangement and as a schematic central section of a floor, wherein the separator rotor is assigned to an outlet pipe for the separator air mixture and solid particles.

Fig. 2a shows an embodiment of an air separator analogous to Fig. 2, however, with rinsing the gap of the separator 8a and passing the shaft 35b.

Fig. 3 shows in a schematic representation and in vertical section the rotor of an air separator.

Fig. 3a shows in a schematic representation and in vertical section the air separator rotor in analogy to Fig. 3, however, with rinsing the gap

- a separator 8a and a shaft 35b.

[0088] In Fig. 1 is shown an embodiment of a jet mill 1 with a cylindrical body 2, which includes a grinding chamber 3, a feeder 4 in about half the height of the grinding chamber 3, at least one grinding mill inlet 5 in the lower region of the grinding chamber 3 and a product outlet 6 in the upper region of the grinding chamber 3. There is an air separator 7 with a rotatable impeller of the separator 8, with which the ground material is classified (not shown) so that only the milled material below a certain grain size is discharged from the milling chamber 3 through the product outlet 6 and the milled material with a grain size above the selected one values ​​lead to further grinding.

[0089] The rotor of separator 8 can be a common rotor used in air separators whose paddles (see later, e.g. in the context of Fig. 3) limit the radially extending spaces between the blades on which the outer ends of the air intake for classification and attract particles of smaller size grains or mass to the central outlet and the outlet of the product 6, while larger particles or molecules with a larger mass are rejected under the influence of centrifugal force. The air separator 7 and / or at least its impeller 8 is particularly preferably provided with at least one design feature according to EP 0 472 930 B1.

Only one inlet of the grinding stream 5 can be provided, e.g. consisting of only one radially inlet or inlet nozzle 9 so that particles of grind material get from the feed 4 into the region of the grinding stream 10 with high energy. only one grinding mill 10 and decompose particles of ground material into smaller constituent molecules that are sucked by the rotor of the separator 8 and, if they have a correspondingly small size or mass, directed through the outlet of the product 6 outwards. However, better efficiency is obtained with diametrically opposed inlets of grinding mills 5, forming two colliding grinding jets 10, causing more intense disintegration of particles than is possible with only one grinding stream 10,

Preferably, two or more inlets of milling jets, preferably grinding nozzles, in particular grinding jet inlets 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12, placed in the lower third part of the preferably cylindrical chamber of the chamber are used. grinding. These grinding jet inlets are ideally arranged in one plane and uniformly around the circumference of the grinding tank, so that all grinding radii meet at one point in the interior of the grinding tank. Particularly preferably, the grinding radiuses or nozzles are evenly distributed around the circumference of the grinding tank. With three grinding streams, this would be an angle of 120 ° between individual inlets or nozzles. Generally, it can be said that the larger the milling space, the more inlets or grinding nozzles are used.

[0092] In a preferred embodiment of the method according to the invention, the grinding space may additionally have, in addition to the grinding jet inlets, heating holes 5 a, preferably in the form of heating nozzles, through which in the heating phase,

- 16 introduce hot gas into the mill. These nozzles or openings - as previously described - can be arranged in the same plane with the openings or grinding nozzles 5. One / one, but preferably also more, more preferably 2, 3, 4, 5, 6, 7 can be included, or 8 holes or heating nozzles 5a.

[0093] In a particularly highly preferred embodiment, the mill comprises two nozzles or heating openings and three nozzles or grinding openings.

[0094] In addition, it is also possible to influence the processing temperature by using an internal heating source 11 between the grinding material feeder 4 and the grinding media region 10 or the respective heating source 12 in the area outside the grinding material feeder 4 or by processing the particles anyway a warm minced material getting in the avoidance of heat losses to the minced material feeder 4, to which the supply pipe 13 is surrounded by a thermally insulating jacket 14. The heating source 11 or 12, if used, can be essentially arbitrary and can therefore be selected functionally and according to market availability, therefore further clarifications are not necessary.

[0095] Especially for the temperature, the temperature of the grinding jet or milling streams 10 is important, and the temperature of the milled material should at least approximately correspond to the temperature of the grinding jet.

[0096] For superheating of the grinding streams 5 inserted into the grinding chamber 3, superheated steam is used in this embodiment. It should be assumed that the heat of water vapor behind the inlet nozzle 9 of the respective inlet of the grinding jet 5 is not significantly smaller than before this inlet nozzle 9. Since the energy required for the impact crumbling should initially be available as the stream energy, the pressure drop between the inlet 15 the inlet nozzle 9 and its outlet 16 will be significant (the pressure energy will be largely transformed into the energy of the stream), and the temperature drop will be considerable. Especially this temperature drop should be sufficiently compensated for by heating the ground material,

[0097] In order to shape and adapt the grinding jet 10 from superheated steam, especially in the form of a closed system, reference is made to DE 198 24 062 A1, the entire disclosure of which in order to avoid identical acquisition itself is incorporated herein by reference. By means of a closed system, it is possible, for example, to grind hot slag as a ground material with an optimum efficiency ratio.

When presenting this embodiment of the jet mill 1, any supply of the propellant B replaces a reservoir or production device 18, illustrating, for example, a reservoir 18a from where the driving means B is guided by the line devices 19 to the inlet of the grinding stream 5 or the inlets of the grinding streams 5 in to produce a grinding jet 10 or

- 17 grinding streams 10 ...

[0099] In particular, starting from a jet mill 1 equipped with an air separator 7, the respective embodiments have been planned and should be understood by way of example only and not limitingly, the jet mill with an integrated dynamic air separator 7 is used to make the finest particles. The innovation over conventional jet mills lies in the fact that the milling phase precedes the heating phase in which all steam-contacting parts are heated to a temperature above the dew-point of the steam, and the fact that an integrated air separator is preferably used is that the rotational speed of the separator rotor or of the separator wheel 8 of the air separator 7 and the internal gain ratio V (= Di / DF) is preferably selected,

[0100] By referring to the above-described variant with superheated steam as driving means B or as an alternative to this, it is particularly advantageous to use as gases or vapor propellants B, exhibiting a higher, and especially significantly higher, acoustic velocity than air (343 m / s). s). Especially as driving means, gases or steam B are used, having an acoustic velocity of at least 450 m / s. In this way, the production and recovery of the finest particles is significantly improved compared to processes with other propellants, used conventionally in accordance with the knowledge of practice, and thus together optimizes the process.

[0101] As the driving means B, fluid, preferably the already mentioned water vapor, but also hydrogen gas or helium gas is used.

[0102] In a preferred embodiment, the jet mill 1, in particular in the case of a fluidized bed jet mill or a compact fluid jet mill or spiral jet mill, with an integrated dynamic air separator 7 for producing ultrafine particles is suitably shaped or arranged or equipped accordingly. in appropriate devices, that the rotational speed of the separator rotor or separator wheel 8 of the air separator 7 and the internal gain ratio V (= Di / DF) are selected or adjusted or adjusted or controlled so that the peripheral speed of the driving means B on the diving tube or nozzle 20 reaches up to 0.8 times, preferably up to 0.7 times and particularly preferably up to 0.6 times the acoustic velocity of the driving means B.

[0103] Furthermore, the jet mill 1 is preferably provided with a source, such as a steam or vapor reservoir or superheated or superheated steam or other suitable reservoir or productive device, for the propelling means B, or a source of the medium associated therewith. a power source from which it is powered for use by a driving means B having a higher and especially a significantly higher acoustic velocity than air (343 m / s), as preferably at a speed

- 18 acoustic at least 450 m / s. This source of driving means, such as a steam or superheated reservoir or steam generation device or superheated steam, contains gases or steam B for use in the operation of the jet mill 1, in particular the above-mentioned steam, with hydrogen gas or alternatively preferred alternatives. helium gas.

[0104] In particular, when using steam as hot propellant B, it is advantageous to provide for inlet or grinding nozzles 9 provided with (not shown) expansion arches of the line devices 19, which should then also be referred to as steam supply lines, i.e. preferably when the steam supply lines are connected to the steam source as a reservoir or generation device 18.

[0105] A further advantageous aspect when using steam as the driving means B is to give the grinding mill 1 the smallest possible surface, or in other words to optimize the jet mill 1 in view of the smallest possible surface area. In the context of steam as the propellant B, it is particularly advantageous to avoid heat exchange or heat loss in the system, and thus energy loss. A further alternative or additional shape means also serves this purpose, namely designing or optimizing the components of the jet mill 1 in order to avoid mass accumulation. This can, for example, be accomplished by using the thinnest flanges in the line devices 19 and for connecting the line devices 19.

[0106] In addition, energy losses as well as other adverse effects for flow can be limited or avoided if the components of the jet mill 1 are designed or optimized to avoid condensation. For this purpose, it is even possible to use (not shown) special devices to avoid condensation. In addition, it is advantageous if the flow paths are at least substantially free of protrusions or optimized in this respect. In other words, through these design variants, the principle of avoiding as much as possible or anything that can become cold, leading to condensation, is realized individually or in any combination.

[0107] It is also advantageous and therefore advantageous when the separator rotor with the decreasing radius has an increasing height in the direction of its axis in the light, in particular the flow-like surface of the separator's rotor is at least approximately constant. . First, or alternatively, an outlet chamber of a finely ground material may be provided, exhibiting a flow-increasing cross-section.

[0108] A particularly advantageous configuration of the jet mill 1 is that the rotor of the separator 8 has an interchangeable rotating diving tube 20.

[0109] In the following, with reference to Figures 2 and 3, further details and variants of the preferred embodiments of the jet mill 1 and its components will be explained.

[0110] The jet mill 1 preferably comprises, as shown schematically in Figure 2, an integrated air separator 7, for example in the case of constructions

- a jet mill as a fluidized bed jet mill as a compact fluidized jet mill or as a spiral jet mill with a dynamic air separator 7, preferably located in the middle of the jet mill 3 of the jet mill 1. Depending on the gas flow rate of the grinding gas, the separator may be impact on the expected fineness of the ground material.

At the air separator 7 of the jet mill 1 according to Fig. 2, the entire vertical air separator 7 is surrounded by the body of the separator 21, consisting essentially of the upper body 22 and the lower body part 23. The upper body part 22 and the lower body part 23 bear on the upper or lower edge by one outwardly oriented circumferential flange 24 or 25. Both circumferential flanges 24 and 25 are located in the built-in or functional state of the air separator 8 on top of each other and are by respective means set relative to each other. Suitable means for fixing are, for example, screw joints (not shown). Loose fasteners can also be used as clamps (not shown) or the like.

[0112] At virtually any point in the circumference of the flange, both circumferential flanges 24 and 25 are mutually connected by articulation 26 so that the upper housing portion 22 can be loosened by means of the flange connecting means towards the lower body part 23 in the direction of the arrow 27 and the upper part body 22 is accessible from below and the lower part of body 23 from above. The lower part of the body 23 is in its turn formed in two parts and essentially consists of a cylindrical body of the sifting space 28 with a circumferential flange 25 at its upper open end and a downward conical discharge cone. The unloading cone 29 and the screening chamber body 28 are located on the upper or lower end with flanges 30, 31 on top of each other, and both flanges 30, 31 of the unloading cone 29 and the screening body case 28 are like circumferential flanges 24, 25 interconnected by loosening (not shown) fastening means. The composite air separator body 21 is suspended in or on the supporting arms 28a, several of which are spaced as evenly spaced around the periphery of the separator body or compressor 21 of the air jet separator 7 of the jet mill 1 and attached to the cylindrical body of the grinding space 28.

[0113] An important part of the built-in elements of the air separator body 7 is the impeller of the separator 8 with the upper disc of the cover 32, with the lower disc of the lid 33 at the outflow side located between the outer edges of both covers 32 and 33, connected to each other. with them permanently and evenly distributed around the rotor of the separator 8 with blades 34 with functional contours. In this air separator 7 the rotor of the separator 8 is driven by the upper disc of the cover 32, while the lower disc of the cover 33 is the cover disc on the discharge side. The rotor of the separator 8 includes a rotatably driven rotor shaft of the separator 35, led out by the upper end from the body of the separator 21 and lifting with the lower end inside the separator body 21 in a one-sided bearing,

The rotor of the separator shaft 35 is discharged from the body of the separator 21 in a pair of machined plates 36, 37 closing the separator body 21 at the upper end of the upwardly extending cone of the body section 38, which guides the rotor shaft of the separator 35 and In this way, the upper plate 36 can be assigned as a torsion-resistant flange to the rotor shaft of the separator 35 and pivotally supported by a pivot bearing 35a on the bottom plate 37, which is associated with its side to the rotary shaft of the separator shaft 35. The lower side of the cover disk 33 on the outflow side lies in a common plane between the circumferential flanges 24 and 25, i.e.that the rotor of the separator 8 is entirely within the foldable upper part of the body 22. In addition, in the region of the conical end section of the body 38, in the upper part of the body 22 there is a tubular product feed nozzle 39 of ground material 4, whose longitudinal axis extends parallel to the axis rotating the rotor of the separator 8 and its drive or separating shaft 35 and which is positioned as far away as possible from this rotational axis 40 of the separator 8 and its drive shaft or separator 35 on the upper body portion 22 lying radially outwards.the longitudinal axis of which runs parallel to the rotational axis 40 of the rotor of the separator 8 and its drive or separating shaft 35 and which is located as far away from this axis of rotation 40 of the rotor of the separator 8 and its drive shaft or separator 35 on the upper part of the body 22 lying radially outside .the longitudinal axis of which runs parallel to the rotational axis 40 of the rotor of the separator 8 and its drive or separating shaft 35 and which is located as far away from this axis of rotation 40 of the rotor of the separator 8 and its drive shaft or separator 35 on the upper part of the body 22 lying radially outside .

[0114] In a particularly preferred embodiment according to figures 2a and 3a, the integrated dynamic air separator 1 includes, as already explained, the separator rotor 8 and the separator shaft 35 and the separator body. A gap is defined between the rotor of the separator 8 and the separator body 21 the separator 8a, and between the separator shaft of the separator and the separator body 21, the formed passageway of the shaft 35b (see with reference to figures 2a and 3a). Especially from the jet mill 1 equipped with this type of air separator 7, where the relevant embodiments are to be understood only by way of example and not as limiting, the jet mill 1 with an integrated dynamic air separator 7 is used to prepare the finest particles. The innovation in relation to conventional jet mills is in addition to the fact that the grinding space is heated before the grinding phase to a temperature above the dew point of the steam, that the separation of the separator slot 8a and / or the shaft passage 35b takes place with compressed low energy gases. A special feature of this design is the combination of the use of these low-energy compressed gases with energy-rich superheated steam, which the mill is fed through the grinding media inlets, in particular through grinding nozzles or grinding nozzles in them. At the same time, high energy and low energy factors are used simultaneously. that the rinsing of the gap of the separator 8a and / or the passage of the shaft 35b takes place with compressed low-energy gases. A special feature of this design is the combination of the use of these low-energy compressed gases with energy-rich superheated steam, which the mill is fed through the grinding media inlets, in particular through grinding nozzles or grinding nozzles in them. At the same time, high energy and low energy factors are used simultaneously. that the rinsing of the gap of the separator 8a and / or the passage of the shaft 35b takes place with compressed low-energy gases. A special feature of this design is the combination of the use of these low-energy compressed gases with energy-rich superheated steam, which the mill is fed through the grinding media inlets, in particular through grinding nozzles or grinding nozzles in them. At the same time, high energy and low energy factors are used simultaneously.

[0115] In the embodiment according to both figures 2 and 3 or 2a and 3a, the separator body 21 places a tubular outlet 20 located on a common axis with the impeller of the separator 8, located at the upper end just below the cover disc 33 on the outlet side of the separator rotor 8, not however, being connected with it. A tube-like shape is also attached to the lower end formed as the outlet pipe 20 on the same axis, the outlet chamber 41 however, the diameter of which is significantly larger than the diameter of the outlet nozzle 20, and in this embodiment at least twice

21 is greater than the diameter of the outlet nozzle 20. There is therefore a clear pitch in the transition between the outlet nozzle 20 and the outlet chamber 41. The outlet nozzle 20 is inserted into the upper cover plate 42 of the outlet chamber 41. At the bottom, the outlet chamber 41 is closed with a removable cover 43. The construction unit from the outlet nozzle 20 and the outlet chamber 41 holds several support arms 44 starfully uniformly around the circumference of the construction unit, permanently connected to the inner ends in the region of the outlet nozzle 20 with a construction unit and fixed by external ends on the body of the separator 21.

[0116] The outlet nozzle 20 is surrounded by a conical annular body whose lower, larger outer diameter corresponds at least approximately to the diameter of the outlet chamber 41 and whose upper, smaller outer diameter corresponds at least to about the rotor diameter of the separator 8. The support arms 44 end in the conical wall of the annular body 45 and are permanently connected to this wall, which for its part is again part of the construction unit from the outlet nozzle 20 and the outlet chamber 41.

[0117] The support arms 44 and the annular body 45 are parts (not shown) of the rinsing air device, the rinsing air preventing the material from entering inside the separator body 21 into the gap between the rotor of the separator 8 or more precisely its lower cover disc 3 and the outlet nozzle 20. this rinsing air could enter the annular body 45 and from there to the slotted gap, the support arms 44 are formed as tubes, guided over the outer end portions through the wall of the separator body 21 and connected via a suction filter 46 to a (not shown) rinsing air source. The annular body 45 is ended upwards with a sieve plate 47,

[0118] The outlet from the outlet chamber 41 forms a fine-grained material discharge tube 48, inserted from the outside into the separator body 21 and tangentially connected to the outlet chamber 41. The fine-grained gas discharge tube 48 is part of the product outlet 6. As the outlet for the discharge pipe of the material finely ground 48, a jet cone 49 serves to the outlet chamber 41.

[0119] At the lower end of the conical end section of the body 38 to the end portion of the body 38, the inlet spiral of the separating air 50 and the coarse material exit 51 are assigned in a horizontal arrangement. The direction of rotation of the inlet air separating spiral 50 is opposite to the direction of rotation of the separator 8. Material output The thick 51 is assigned as removable to the end section of the body 38, with the flange 52 being assigned to the lower end of the end portion 38 and the flange 51 to the upper end of the coarse material 51, and in turn the two flanges 52 and 53 are mutually connected by releasably known means when the air separator 7 is ready for operation.

[0120] The planned dispersion zone is marked as 54. Machined (chamfered) on the inner edge of the flanges for clean flow guiding and straight lining are

- 22 marked as 55.

[0121] Finally, an interchangeable protective tube 56 adheres to the inner wall of the outlet nozzle 20 and the corresponding replaceable protection tube 57 can abut against the inner wall of the outlet chamber 41.

[0122] At the beginning of the operation of the air separator 7 in the illustrated operating state, the air separator 7 is introduced through the inlet air spiral at a pressure drop and the separating air selected according to the inlet speed. As a result of the introduction of the separating air by means of the spiral, in particular in connection with the conicity of the final section of the body 38, the separating air spirals upwards into the rotor region of the separator 8. At the same time, through the product feed port 39, the "product" of solid particles of different mass is introduced into the body separator 21. Thick material from this product, i.e. the proportion of particles with a larger mass, it gets in the opposite direction to the separating air to the exit area of ​​the coarse material 51 and is made available for further processing. The finely ground material, i.e. the proportion of particles of lower mass, is mixed with the separating air, radially extends from the outside inward through the separator rotor 8 to the outlet nozzle 20, into the outlet chamber 41 and finally through the finely ground outlet tube 48 to the material outlet finely ground and from there to the filter, in which the driving fluid in the form of a fluid, such as air, and finely ground material are separated. The thicker components of the finely ground material are centrifuged centrifugally from the rotor of the separator 8 and mixed with the coarse material to leave the body of the separator 21 with the coarse material,

[0123] As a consequence of the sudden widening of the cross section between the outlet nozzle 20 and the outlet chamber 41, there is a marked reduction in the speed of the mixture of fines and air. This mixture thus enters at a very low flow rate through the outlet chamber 41 through the finely grit exhaust pipe 48 to the finely grit outlet 58 and produces only slight abrasion on the wall of the outlet chamber 41. Therefore the protective tube 57 is also only the center of the highest foresight . Due to the good separation technique, the flow velocity in the rotor of the separator 8 still prevails in the outlet or in the discharge port 20, therefore the protective pipe 56 is more important than the protective pipe 57.

Furthermore, the air separator 7 can be well conserved by dividing the body of the separator 21 in the manner described and assigning the separator components to individual parts of the body, and the damaged components can be replaced at relatively low expenditure and within short maintenance times.

[0125] While in the schematic representation of Fig. 2 or 2a, the rotor of the separator 8 from

Both of the discs 32 and 33 and between the paddles blade paddles 59 and paddles 34 are shown in the already known usual form with parallel and parallelepiped discs of covers 32 and 33, whereas in Fig. 3 and 3a, the separator rotor 8 is shown in a modification preferred for the further embodiment of the air separator 7.

[0126] The rotor of the separator 8 according to Fig. 3 or 3a additionally comprises a blades disc 59 with blades 34, an upper cover disc 32 and axially spaced lower cover disc 33 on the discharge side and can rotate about a rotation axis 40, and thus the longitudinal axis of the air separator 7. The diagonal extent of the rotor of the separator 8 is perpendicular to the axis of rotation 40, i.e. to the longitudinal axis of the air separator 7, regardless of whether the axis of rotation 40 and thus said longitudinal axis is vertically oriented or running horizontally. The lower cover disk 33 from the discharge side circumferentially surrounds the outlet nozzle 20. The blades 34 are connected to both discs of the covers 33 and 32. Both cover plates 32 and 33 are now convexly shaped differently from the prior art, preferably in such a way, that the distance between the upper lid disc 32 and the cover disk 33 on the outflow side increases from the rim 59 of the blades 34 into the interior, i.e. to the axis of rotation 40, preferably continuously, e.g. linearly or non-linearly, and particularly preferably so that the surface of the skirt the flow cylinder for each radius between the blade outlet edges and the outlet nozzle 20 remains at least approximately constant. The outflow velocity, which decreases in the known solutions due to the decreasing radius, remains at least more or less constant in this solution. that the surface of the shell of the flow cylinder for each radius between the blade outlet edges and the outlet nozzle 20 remains at least approximately constant. The outflow velocity, which decreases in the known solutions due to the decreasing radius, remains at least more or less constant in this solution. that the surface of the shell of the flow cylinder for each radius between the blade outlet edges and the outlet nozzle 20 remains at least approximately constant. The outflow velocity, which decreases in the known solutions due to the decreasing radius, remains at least more or less constant in this solution.

[0127] In addition to the embodiment of the top cover disc 32 and the lower cover disk 33 explained above and in Figs. 3 and 3a, it is also possible that only one of the two cover plates 32 or 33 is conically shaped in the manner explained and the other cover disk 33 or 32 flat, as is the case with both cover plates 32 and 33 in the context of the embodiment according to fig. 2. The non-parallelepiped shape of the cover disk can in particular be of such a kind that the surface of the shell of the flow cylinder for each radius between the blade shoulder edges and outlet port 20 remained at least approximately constant.

[0128] An important step for determining the density of silanol groups and the arrangement of silanol groups on the surface of the precipitated silicic acid, in addition to the precipitation at which the chain structure is built, is tempering in step 5. This tempering can be carried out in series or continuously. For tempering, for example, a fluidized bed (fluidized bed), fluidized bed or rotary bed reactor may be used. In this regard, care should be taken that during tempering a homogeneous temperature distribution and a homogeneous atmosphere of process gases are ensured so that all particles of precipitated silicic acid are subjected to the same conditions. The process gas must have a sufficient concentration of water vapor. Preferably, the water vapor concentration is 10 to 95% by volume, particularly preferably 40 to 90% by weight,

[0129] In particular when using a rotary tubular reactor, care must be taken that the temperatures are uniform throughout, i.e. there are no "cold zones" in which condensation could condense. Condensed water vapor may cause the precipitation of precipitated silicas. The special tempering conditions according to the invention therefore also ensure that the pre-tempered silicic acid does not have to be ground once after tempering, i.e. no sinters or lumps are formed which would have to be removed again by grinding after tempering.

[0130] Preferably, a fluidized (vortex) or fluidized bed reactor is used. The fluidized bed (vortex) is understood as follows:

When the particulate material lying on the horizontal, perforated bottom is subjected to gas flow from below, then under certain flow conditions a condition is created that resembles a boiling liquid; the layer ejects bubbles; the particles of loose material are inside the layer in a continuous, rotating upward and downward motion and thus remain in a certain sense in a suspended state. Therefore, it is also said about the lifting bed, the vortex bed, the fluidized bed, and the fluidization. The associated large surface area of ​​fluidized material also facilitates the drying and annealing of solid bodies.

[0131] It is important that during tempering all particles of the precipitated silicic acid are subjected to the same temperature and the same process gas. Temperature differences between the hottest and coldest places should be as small as possible. Therefore, the temperature of the filter candles must not be less than the temperature of the product.

[0132] Particularly very preferably, tempering takes place in step 5 of the process according to the invention according to the following partial steps 5a) to 5e):

5a. Filling of the fluidized bed reactor with precipitated silicic acid,

5b. Reactor heating to 300 to 800 ° C, at the same time the reactor is vented with an inert gas and / or a nitrogen-air mixture so that the fluidization velocity is set from 0.02 to 0.06 m / s,

5c. Administration of a gas mixture I from steam and an inert gas, e.g. nitrogen, or a gas mixture II from steam, inert gas and air at 300 to 800 ° C for a time of 0.25 to 6 hours, whereby the gas mixture ventilates the reactor at a rate of fluidization from 0.02 to 0.06 m / s and gas mixtures I and II have a water vapor concentration of 10 to 95 vol.% and for gas mixtures II an oxygen content of 0.01 to 21 vol.%.

5d. Interruption of steam supply and vapor displacement by inert gas, e.g. nitrogen, and / or inert gas-air mixture at 300 to 800 ° C, the gas or gas mixture flowing through the reactor at a fluidization velocity from 0.02 to 0.06 m In the case of using a gas-air mixture, it has an oxygen content of 0.01 to 21% by volume.

5e. Cooling of tempered precipitated silicic acid to temperature

- the room is carried out in a dry process atmosphere, with the inert gas-air mixture having an oxygen content of 0.01 to 21% by volume. [0133] In this case, after filling the fluidized bed (suspension) reactor with precipitated silicic acid (step partial 5a)), the reactor is heated in partial step 5b) to an operating temperature of 300 to 800 ° C, preferably 350 to 690 ° C and particularly preferably 400 to 650 ° C. During the heating operation, the reactor is vented with an inert gas, preferably nitrogen and / or a mixture of inert gas and dry air, such that the fluidization velocity is set from 0.02 to 0.06 m / s, [0134] Once the operating temperature is reached through the reactor at partial step 5c), a gas mixture I is passed from steam and inert gas, preferably nitrogen, or a gas mixture II from steam, inert gas and air for a time of from 0.25 to 6 h, preferably 0.5 to 5 h, particularly preferably 1 to 4 h, particularly very preferably 2 to 4 h. The speed of fluidization of the gas mixture is 0.02 to 0.06 m / s. Mixtures I and II have a water vapor concentration of 10 to 95 vol.%, Preferably 40 to 90 weight%, particularly very preferably 50 to 90 weight% and for gas mixtures II, an oxygen content of 0.01 to 21 vol.%.

[0135] The material obtained according to step 5 or step 6 is acidified to pH = 3-5, in addition to pH 4-5. This is preferably effected by a gaseous acidifier, particularly preferably gaseous hydrochloric acid and / or HBr and / or nitrogen oxides and / or steam SO3 and / or steam

SOCl2.

[0136] In a first embodiment of the method according to the invention, acidification occurs by contacting at least one acidulent with the precipitated silicic acid obtained according to step 5 or 6.

[0137] In a second embodiment, acidification is effected by mixing the acidified and non-acidified fraction of the precipitated silicic acid of the invention. In this embodiment, the material obtained according to step 5 or 6 is divided into fraction A and fraction B. Fraction A is acidified by contacting an acidulent, preferably gaseous HCl. After acidification, fraction A is optionally rinsed with an inert gas, particularly preferably with nitrogen. Fraction A is preferably acidified to a pH of 2 - 4, in addition to a pH value of 4. To the acidified fraction A, so much material from fraction B is added until the pH is equal to 3-5, in addition to a pH of 4-5. The course of acidification and mixing can be repeated until the desired pH value is reached.

[0138] Irrespective of whether the acidification is carried out according to Embodiment 1 or 2, after completion of the acidification, it may be followed by rinsing with an inert gas, preferably nitrogen, to remove residues acidifying the surface of the precipitated silicic acid.

[0139] The precipitated silicas of the invention can be used in sealants, in particular in silicone rubber or silicone sealants, and particularly preferably in RTV-1K sealing compounds. It is possible to use in various crosslinking systems, e.g., acetoxy-crosslinking, alkoxy-crosslinking and oxime-crosslinking systems. These systems are used, for example, in the construction industry as sealing compounds for joints, in the automotive industry as adhesive and sealing material and as coating compounds for textile fabrics.

[0140] The reaction conditions and physical / chemical data of the precipitated silicas of the invention are determined by the following methods:

Examination of solids content in the filter cake [0141] According to this method, the solids content in the filter cake is tested by removing volatiles at 105 ° C.

[0142] 100.0 g of filter cake (weight E) was weighed into the interior of a dry, porcelain bowl (diameter 20 cm). Alternatively, the filter cake was ground with a spatula to obtain loose pieces with a maximum size of 1 cm³The sample was dried at 105 ± 2 ° C in a drying cabinet until its weight was stabilized. The sample was then cooled to room temperature in a desiccator using silica gel as a drying agent. Weight A is determined gravimetrically.

[0143] The solids content (FG) in% is determined according to FG = A / E * 100%, with A = the weight (final) of the weight E = the weight in g.

Determination of the solids content of suspending suspensions [0144] The contents of the solid suspensions are determined gravimetrically after the sample has been filtered.

[0145] At room temperature, 100.0 mL of a homogeneous suspension (V-suspension) was measured using a graduated cylinder. The sample was filtered using a round filter (TYPE 572, manufacturer: Schleicher & Schuell) on a porcelain suture, nevertheless not soaked to dryness to prevent filter cake from breaking. The filter cake was then rinsed with 100.0 ml of distilled water. The rinsed filter cake was transferred to a porcelain bowl and dried at 105 ± 2 ° C in a drying oven until the weight was stabilized. After cooling to room temperature, the weight of the dried precipitated silicic acid is measured^(ma sample^). [0146] The solid content is determined according to:

Solid substance content in g / l = (mpróbka wg) / (Vzawiesiny wl)

Determination of solid product content based on precipitated silicic acid [0147] The product based on precipitated silicic acid is dried in an infrared (IR) dryer until the weight is stabilized. Loss on drying usually consists of water humidity.

[0148] The tarnished aluminum pan is filled with 2.0 g of a product based on precipitated silicic acid and the lid of the IR dryer unit is closed (Companies

- 27 Mettler, Type LP 16). After pressing the start button, the slurry starts drying at 105 ° C, which ends automatically when the weight drop per time unit drops below 2 mg / (120 s).

[0149] The weight loss in% is shown directly by the device when mode% 0-100 is selected. The content of a solid substance is given by

Solid content in% = 100% - weight loss in%.

Determination of the pH value [0150] The pH of the precipitated silicic acid is determined as a 5% aqueous suspension at room temperature based on DIN EN ISO 787-9. Compared to the requirements of this standard, the total weight was changed (5.00 g of silicic acid per 100 ml of deionized water).

Electrical conductivity test [0151] The electrical conductivity of the precipitated silicic acid is determined as 4% of this aqueous suspension at room temperature based on DIN EN ISO 787-14. Compared to the requirements of this standard, the total weight was changed (4.00 g of precipitated silicic acid per 100 ml of deionized water).

Moisture test or dehydratation after drying [0152] Moisture of precipitated silicic acid is determined according to ISO 787-2 after drying for 2 hours in a circulating air dryer at 105 ° C. The loss on drying is mainly the loss of water.

Determination of the loss on ignition [0153] According to this method, the weight loss of the precipitated silicic acid is determined based on DIN EN ISO 3262-1 at 1000 ° C. At this temperature, physically and chemically bound water evaporates as well as other volatile components. Moisture (TV) of the test sample is determined according to the previously described method "Determination of moisture or moisture loss" based on DIN EN ISO 787-2.

[0154] 0.5 g of powdered, spherical or granular precipitated silicic acid is weighed to an accuracy of 0.1 mg to the previously baked, milled porcelain crucible (sample E). The test is heated for 2 h at 1000 ± 50 ° C in a muffle furnace. The porcelain crucible was then cooled to room temperature in a desiccator using silica gel as a drying agent. Weight A is determined gravimetrically.

[0155] The loss on ignition (DIN) GV in% is obtained according to GV = (1 - A / F) * 100% [0156] F means the corrected weight with respect to the dried substance in g is calculated according to

F = E * (1 - TV / 100) [0157] Designations in calculation A = weight (final) in g, E = weight of TV =

- 28 loss on drying in%.

Determination of the BET surface [0158] The specific surface area of ​​nitrogen (then called the BET surface) for powdered, ball or granulated precipitated silicic acid is determined based on ISO 5794-1 / Annex D by the TRISTAR 3000 device (by Micromeritics) according to the multipoint designation according to DIN-ISO 9277.

CTAB surface determination [0159] The method is based on the adsorption of CTAB (N-hexadecyl-N, N, N-trimethylammonium bromide) on the surface of the "outer" precipitated silicic acid, based on ASTM 3765 or NFT 45-007 (Chapter 5.12.1.3 ).

[0160] The adsorption of CTAB takes place in an aqueous solution with continuous mixing and treatment using ultrasound. Excessive, unadsorbed CTAB is tested by excess titration using NDSS (sodium docusate solution, AOT solution) and titration equipment, the completion being accompanied by a maximum turbidity of the solution, determined by means of a phototrode. The temperature during the entire process is 23-25 ​​° C, which helps counteract the crystallization of CTAB. Titrating excess is described by the following equation:

(C20H37O4) SO₃Na + BrN (CH₃) 3 (Ci6H₃3) F> (C2oH3704) S03N (CH3) 3 (C₁₆H33) + NaBr

NDSS CTAB

Apparatus [0161] METTLER Toledo titration apparatus, model DL 55, and METTLER Toledo titration apparatus, model DL 70, each equipped with: pH electrode, Fabrikat Mettler, model DG 111, and phototrode, Fabrikat Mettler, model DP 550.

Tank for titration, 100 ml, made of polypropylene

Glass titration tank, 150 ml, with lid

Pressure filtering device, 100 ml content

Membrane filter made of cellulose nitrate, pore size 0.1 μm, 47 mm 0, e.g. Whatman (Best. No. 7181-004)

Reagents [0162] CTAB solutions (0.015 mol / l in deionized water) and NDSS (concentration 0.00423 mol / l in deionized water) ready for use (Bernd Kraft GmbH, 47167 Duisburg: order number 6056.4700, CTAB solution in a concentration of 0.015 mol / Order No. 6057.4700, NDSS solution 0.00423 mol / l), stored at 25 ° C and consumed within one month.

Procedure

1. Titration using a blank test

[0163] One day, before each series of measurements, the consumption of the NDSS solution for titration with 5 ml of CTAB solution should be examined. For this purpose, the phototrode is determined before starting the titration at the level of 1000 ± 20 mV (which corresponds to 100% transparency).

[0164] To the titration tank, approximately 5.0 ml of CTAB solution are pipetted with pipet , followed by 50.0 ml of deionized water. The titration with the NDSS solution is carried out - with constant mixing - based on the measurement method known to the specialist using the DL 55 titration device until the maximum opacity of the solution is obtained. The V1 consumption of the NDSS solution in ml is determined. Each titration should be carried out three times.

2. Adsorption 10.0 g of powdered, spherical or granular silicic acid with a moisture content of 5 ± 2% (optionally the moisture content is determined by drying at 105 ° C in a drying oven or by uniformly moisturizing) crushed by 30 seconds with the help of a mill (Krups, model KM 75, article no. 2030-70). Exactly 500.0 mg of the particulate sample (weight E) was carried into a 150 ml titration tank by means of a magnetic stirrer, after which 100.0 ml of CTAB (T1) solution was added exactly. The titration tank was closed with the aid of a lid, after which the contents were mixed with a Ultra Turrax T 25 stirrer (stirrer shaft KV-18G, diameter 18 mm) for a maximum of 1 minute until full crosslinking, at (rotational speed) 18000 revs / min.

[0166] The suspension inside the titration tank was treated for 4 minutes by ultrasound sonication (from Bandelin, Sonorex RK 106 S, 35 kHz 100 W nominal or 200 W maximal power) at 25 ° C. Then, pressure filtration was carried out using a membrane filter at a nitrogen pressure (atmosphere) of 1.2 bar. The first part of the mixture in the amount of 5 ml is discarded.

3. Titration [0167] 5.00 ml of the remaining filtrate is pipetted into a 100 ml titration vessel, followed by deionized water to 50.0 ml. The titration tank is screwed to the DL 55 titration unit and, under continuous mixing, the titration is carried out using the NDSS solution until the maximum opacity is obtained. The VB consumption of the NDSS solution is determined in ml. Each titration should be carried out three times.

Calculations [0168]

- 30 CTAB (uncorrected moisture)

<img file="PL2209739T3_D0001.tif" />

VA = Consumption of the NDSS solution in ml when blank titration

VB = Consumption of NDSS solution in ml using filtrate

CCTAB = Concentration of CTAB solution in mol / l

MCTAB = molar mass CTAB = 364.46 g / mol

T1 = Added amount of CTAB solution incl

P = the required space for CTAB = 578,435 m2 / g

E = weight of precipitated silicic acid [0169] The surface CTAB refers to the precipitated silicic acid devoid of water content, and the following correction is carried out.

CTAB (uncorrected moisture) in m²/ g * 100%

CTAB =

100% - moisture in% [0170] The moisture of the precipitated silicic acid is determined according to the described method "Determination of moisture".

Determination of DBP Absorption [0171] The DBP absorption coefficient (DBP number), which is a measure of the absorption capacity of precipitated silicic acid, is determined based on DIN 53601 as follows:

Mixing takes place with a small amount of energy and is tracked using a digital indicator. At the end of the study, the mixture became pasty, which was indicated by the rapid increase in energy demand. When displaying at level 600 (torque 0.6 Nm) using an electric switch, the kneader is switched off as well as the DBP dosing. The synchronous motor for DBP power supply is coupled with a digital measuring mechanism, which allows

- 31 for DBP consumption reading in ml.

[0172] The DBP absorption coefficient is given in g / (100 g) and calculated on the basis of the following formula:

<img file="PL2209739T3_D0002.tif" />

where:

DBP = Absorption DBP in g / (100 g)

V = DBP consumption in ml

D = Density of DBP in g / ml (1.047 g / ml at 20 ° C)

E = weight of precipitated silicic acid acc

K = Correction value according to the moisture correction table in g / 100 g) [0173] The DBP absorption coefficient is determined for dry precipitated silicic acid devoid of water content. If moist precipitated silicas are used, the correction value K for the calculation of DBP absorption should be taken into account. This value can be corrected on the basis of the following correction table, e.g. the water content of precipitated silicic acid at 5.8% means an addition of 33 g / (100 g) in the case of DBP absorption. The moisture of the precipitated silicic acid is determined according to the described method of "determining moisture or loss on drying".

Moisture correction table: for the absorption of dibutylphthalate (dehydrated) [0174]

<td>% moisture</td><td>% moisture , 0</td><td>2</td><td>4</td><td>6</td><td>8</td>

<td>0</td><td>0</td><td>2</td><td>4</td><td>5</td><td>7</td>

<td>1</td><td>9</td><td>10</td><td>12</td><td>13</td><td>15</td>

<td>2</td><td>16</td><td>18</td><td>19</td><td>20</td><td>22</td>

<td>3</td><td>23</td><td>24</td><td>26</td><td>27</td><td>28</td>

<td>4</td><td>28</td><td>29</td><td>29</td><td>thirty</td><td>31</td>

<td>5</td><td>31</td><td>32</td><td>32</td><td>33</td><td>33</td>

<td>6</td><td>34</td><td>34</td><td>35</td><td>35</td><td>36</td>

<td>7</td><td>36</td><td>37</td><td>38</td><td>38</td><td>39</td>

<td>8</td><td>39</td><td>40</td><td>40</td><td>41</td><td>41</td>

<td>9</td><td>42</td><td>43</td><td>43</td><td>44</td><td>44</td>

<td>10</td><td>45</td><td>45</td><td>46</td><td>46</td><td>47</td>

Infrared (IR) determination [0175] By infrared (IR) spectroscopy, various types of SiOH groups (isolated, bridged, + H2O) can be determined. To determine the intensity of various silanol groups, the precipitated silicas are measured as layers of powder. The extinction values ​​of the different silanol groups are divided by the value of the extinction of the connected SiO vibrational bands at 1870 cm^-1 (Standardized).

[0176] Determination by IR (infrared) spectroscopy is carried out with Bruker's FT-IR IFS 85 spectrometer. For the measurement, a NaCl monocrystalline window (round d = 25 mm, h = 5 mm) from K.Korth, Kiel, 0.5 mm Teflon maintainer and window fastener is used. The gap maintainer is laid on a clean and polished NaCl monocrystalline window. The test material is sprayed between the gap maintainer and covered with a further clean and polished NaCl monocrystalline window, the air bubbles can not be closed. Both mono-crystalline NaCl windows with a powder layer are used in the sample mounting. Attachment of the sample is placed on the path of the infrared radiation (IR) beam and the examined space closes. The test space is rinsed before the measurement, cleaned with steam and carbon dioxide, with air. In the adjustment mode, "Align" is performed and the measurement starts.

[0177] The measurement is carried out with the following parameters:

Resolution:

Scanner speed:

Measurement interval:

apodization function: Number of scans _{2 cm}^-1

6; 10.51 Hz

4500 cm^-1 up to 100 cm^-1

triangular

[0178] The spectrum is expressed in the range of wave numbers from 4000 to 1400 cm^-1 in continuous wave numbers.

[0179] The extinction ratio of SiOHisolated is determined as follows (figure 4):

Then, two output values ​​are determined. For this purpose, two tangents are placed on the absorption curve. The first tangent (1st base value) touches the absorption curve in the range of 4,000 cm^-1 up to 3800 cm^-1 as well as in a different range from 3000 cm^-1 up to 2100 cm^-1. Make sure that the tangent does not cross the absorption curve or in the range of 4,000 cm^-1 up to 3800 cm^-1 or in the range of 3000 cm^-1 up to 2100 cm^-1. The second tangent (2nd output value) touches the absorption curve in the range of 2200 cm^-1 up to 2000 cm^-1 as well as in a different range from 1850 cm^-1 up to 1650 cm^-1. Make sure that the tangent does not intersect the absorption curve or in the range of 2200 cm^-1 up to 2000 cm^-1neither in the range of 1850 cm^-1 up to 1650 cm^-1.

[0180] After determining the starting values ​​from the maximum of the relevant beams (3750 and 1870 cm^-1) is plotted perpendicular to the individual output values ​​and the respective maximum heights are measured up to the output value in mm.

The following quotient is created:

- 33 Maximum height to the initial value in mm at 3750 cm^-1

The extinction ratio (SiOH_isolated) =

Maximum height to the initial value in mm at 1870 cm^-1 [0181] Six IR spectra (infrared) are taken from each sample, each time measured using a new test material. Each IR (infrared) spectrum is evaluated according to the method described above each time five times. The extinction ratio (SiOHisolated) is then given as the mean value of all grades.

Determining the contact angle [0182] The contact angle is determined as described in WT Yen, RS Chahal, T. Salman, Can. Underworld. Quart., Vol. 12, No. 3, 1973.

Determining the density of silanol groups [0183] Next, the moisture of the precipitated silicic acid is determined according to "Determining moisture or loss after drying". Subsequently, 2 - 4 g sample (exactly to be determined for 1 mg) is run into a sealed glass apparatus (glass flask with dropping funnel) with the pressure measurement connected. Here, it is dried for 1 h at 120 ° in a vacuum (&lt;1 hPa). At room temperature, about 40 ml of degassed 2% LiAlH4 solution in Diglyme are then added dropwise from the addition funnel. Ew. a further solution is added dropwise until no further increase in pressure is observed. The pressure increase of the hydrogen produced by the reaction of LiAlH4 with the silanol groups of the precipitated silicic acid is determined by measuring the pressure (with the accuracy of &lt;1 hPa before the calibration of the apparatus of known volume). From the pressure increase, the concentration of silanol groups of the precipitated silicic acid can be calculated by the general equation of gases, with the moisture of the precipitated silicic acid being taken into account. The influence of solvent vapor pressure should be corrected accordingly. From the density of silanol groups, it is calculated as follows:

Concentration of silanol groups

Density of silanol groups =

BET surface

Determination of particle size distribution by means of laser diffraction [0184] The particle size distribution is determined according to the laser diffraction principle on a laser diffractometer (Horiba, LA-920).

The sample of the precipitated silicic acid is then subjected to a dispersion in 100 ml of water without the addition of dispersing agents in a 150 ml beaker (diameter: 6 cm), so that a suspension having a SiO2 weight fraction of 1% by weight is formed. This suspension is then subjected to intense dispersion using an ultrasonic finger (Dr. Hielscher UP400s, Sonotrode H7) for a period of 5 min (300 W, non-pulse). For this purpose, an ultrasonic finger (Ultraschallfinger) should be mounted so that its lower end is immersed approximately 1 cm above the bottom of the beaker. Directly after dispersion

34 is determined from a partial ultrasound-processed slurry particle size distribution using a laser diffractometer (Horiba LA-920). For the assessment using the Horiba LA-920 standard software provided, a refractive index of 1.09 should be chosen.

[0186] All measurements take place at room temperature. The particle size distribution as well as significant quantities, such as the particle size d90, are calculated automatically by the device and presented graphically. Observe the instructions in the operating instructions.

Determination of the modified density after tamping [0187] With "traditional" deflection density determination according to DIN EN ISO 787-11, the measurement result can be adulterated by the fact that the precipitated silicic acid has already been pre-compacted, e.g. in packaging. To exclude this for the precipitated silicas of the invention, the "modified paste density" is determined.

[0188] Equipped with a round filter (eg Model 598, company Schleicher + Schull), a porcelain knob (nominal size 110, diameter = 12 cm, height = 5.5 cm) is filled loosely to about 1 cm below the upper edge with precipitated acid silicon and covered with a flexible film (Parafilm®). The shape and dimensions of the flexible film should be chosen so that it closes the edges of the porcelain sutures as completely as possible. The nozzle is deposited on the suction flask and then set for a duration of 5 min under vacuum -0.7 bar. In this case, the evenly precipitated silicic acid is compacted (whipped) by the sucked film. Then, carefully ventilate and remove the resulting plate from the precipitated silicic acid and hummage it by turning it into a porcelain bowl.

The slightly pre-mixed material was evenly redispersed (in the aerosol sense silicic acid / air) via a centrifugal mill (ZM 1, Retsch, sieve insert 0.5 mm, speed stage 1, no cyclone separator, no inner funnel insert) with internal the receiving basin (silicic acid (educt) was introduced slowly - a paddle on the blade - to supply the mill, the inner product receiving bowl should never be completely full). The current consumption of the mill should not exceed 3 amperes. This method was less about classic milling and more about the defined relaxation of the structure of silicic acid (e.g. precipitated silicas ground by air stream), because here the energy input was much weaker than when milling the stream.

[0190] 5 g of the material thus obtained is weighed into a 250 ml measuring cylinder of a compacted volume measuring instrument (Type STAV 2003, from Engelsmann) to an accuracy of 0.1 g. Based on DIN ISO 787-11 reads from a scale in ml of the resulting volume of silicic acid after 1250-times compaction.

1000 ml

Modified density after whipping in [g / l]

The volume after compaction in [ml] [0191] The following examples should explain the invention without limiting it

- 35 extent.

[0192] The water glass and sulfuric acid used at various locations in the following example instructions are characterized as follows:

Water glass: density 1,348 kg / l, 27.0% by weight SiO2, 8.05% by weight Na2O Sulfuric acid: density 1.83 kg / l, 94% by weight.

Example 1 [0193] In a 2 m3 waste container (diameter 160 cm) with blades, a MIG oblique agitation system and a Ekato turbine cutting station, 1680 l of deionized water are placed and heated to 92 ° C. After reaching the temperature, the water glass is dispensed for a duration of 100 min with a dosing speed of 3.93 kg / min and sulfuric acid with a dosing speed of 0.526 kg / min during mixing. The sulfuric acid dosing rate should be adjusted so that the pH value of 8.5 is maintained during the total duration of the precipitation. The dosage of the water glass and the same sulfuric acid dosing rate are then switched off and the acid suspension is acidified further to pH 3. The precipitation suspension has a solid content of 54 g / l.

[0194] The resulting suspension was filtered using a membrane filter press and the filter cake was rinsed with deionized water until a conductivity of &lt;1 mS / cm was found in the water after rinsing. The filter cake then has a solid content of &lt;20%.

[0195] Before drying with the aid of a spray dryer, the filter cake is again dispensed with deionized water to a solid content of 8-13%, with care being taken not to be subjected to strong shearing forces. The dosage of the condensed filter cake in the spray dryer is such that the temperature measured at the dryer outlet is about 150 ° C.

[0196] The spray-dried material is pre-milled through a mechanical beater mill to an average particle size of 10-12 Pm. After this pre-milling, the material is smallest in the water vaporized fluidized bed jet according to Figures 1, 2a and 3a at 38 bar overpressure. The details of the grinding system (mill) used and the grinding methods used can be taken from the above description as well as figures 1,2a and 3a.

[0197] For the preparation of proper grinding by means of heated water vapor, the fluidized bed jet of Figure 1 is heated up with the integrated dynamic air separator according to figures 2a and 31 followed by two heating nozzles (5a) (of which only one is shown in Figure 1) ), which are driven by hot compressed air 10 bar and 160 ° C, up to the exit temperature from a mill equal to approximately 105 ° C.

[0198] A filtration device (not shown in figure 1) is attached to the mill for separating the ground material, the filter housing of which is lower in the third third heated with indirect heat by delivering heat shock with saturated steam (6 bar) to avoid condensation . All surfaces of the device in

- within the mill, the separation filter and the supply lines for steam and hot compressed air are particularly insulated.

[0199] Once the desired preheating temperature has been reached, the hot nozzles are turned off with hot compressed air and the three grinding nozzles are heated with hot water vapor (37.9 bar (abs), 325 ° C) as a grinding medium.

[0200] To protect the filter medium used in the separation filter and to set a specific residual water content of the ground material (see Table 1), the water in the starting phase and during grinding in the grinding space of the mill is fed with a compressed air nozzle made of two materials depending on outlet temperature of the mill.

[0201] The following configurations of mill operation parameters apply: diameter of grinding nozzle nozzles = 2.5 mm, nozzle type = Laval, number of nozzles = 3 pieces; inside pressure of the mill = 1.306 bar (abs.), pressure at the grinder input = 37.9 bar (abs.), temperature at the grinding agent input = 325 ° C, outlet temperature of grinding media mill = 149.8 ° C, speed rotational separator = 3500 min^-1, separator radius = 54.5 A%, diameter of the exit bracket (diameter of the immersion sleeve) = 100 mm.

[0202] The feed of the product starts when the above-mentioned process parameters are constant. Adjustment of the given amount occurs depending on the separator stream setting. The separator stream regulates the amount fed in such a way that approximately 70% of the rated flux can not be exceeded.

[0203] Here, as an introducer (4), there was a drum with adjustable volume dividers, dispensing the feed material from the feed tank to the overpressure grinding chamber through a bar impulse lock serving as a barometric closure.

[0204] The fineness of the coarse material takes place in the vapor streams (grinding gas). Together with the expanded grinding gas, the product particles rise in the middle of the mill tank to the separator rotor. Depending on the rotational speed of the separator and the amount of grinding steam, particles that have the right fineness go with the grinding steam to the output of the fine material, and from there to the connected distribution system, while too coarse particles return to the grinding zone and are subjected to further refining. The output of the separated fines from the separating filter to the following silo and packing takes place via a lock with a baffle drum.

[0205] The grinding pressure of the grinding gas prevailing on the grinding nozzles or the resulting amount of grinding gas in connection with the rotational speed of the dynamic air separator with the scoop wheel determine the fragmentation of the grain size distribution function and the upper grain boundary.

[0206] The material was de? Ned as defined in Table 1 by the d90 value and the proportion of particles &lt;1 .mu.m particle size.

[0207] Next, the material is treated with a fluidized bed reactor

37 (vortex) (height of the suspension bed of the expanded suspension bed about

1.5 m, diameter of the suspension bed about 0.5 m). The following conditions must be maintained:

The fluidized bed reactor with a fluidized bed is then filled with 5 kg of ground powder. A mixture of gases from dry nitrogen and dry air flows through the fluidized bed. Both of these gases are dispensed before entering the reactor in such a way that the resulting oxygen content does not exceed 6% by volume and that the reactor has a fluidization velocity of 0.05 m / s. The reactor is heated from room temperature to 600 ° C. The gas flows in the fluidization gas are set in the heating phase so that the fluidization velocity in the reactor of 0.05 m / s remains constant.

[0208] After reaching 600 ° C for a period of 3 h, a pre-warmed gas mixture of steam and nitrogen is fed to the reactor. Mixing of both components takes place in such a way that a water vapor concentration of 90% and a nitrogen content equal to 10% are set. The amounts of gases are adjusted so that the fluidization velocity is again equal to 0.05 m / s.

[0209] The steam is then stopped and pure nitrogen at 600 ° C is passed through the bubble bed reactor for 30 minutes.

[0210] The material is then cooled in a dry nitrogen stream to room temperature and withdrawn from the reactor. In the cooling phase, be careful not to allow any steam present anymore.

[0211] The material is acidified with HCl gas to pH = 4.3.

[0212] To this end, the material is divided into part A and part B.

[0213] Part A is acidified with HCl gas. For this purpose, 20 g of silicic acid are gassed for 2 minutes (flow around 250 ml / h) at room temperature. The material is then rinsed with nitrogen for 10 minutes.

[0214] After this treatment, the material has a pH value of 3.7.

[0215] To the acidified part A, the material from part B is added until the pH is equal to 4.3.

[0216] The acidification and mixing process can be repeated until the desired number of trials is reached.

[0217] The physicochemical data of Example 1 are listed in Table 1.

Comparative Example [0218] As a comparative example, the precipitated silicic acid obtained according to Example 2 was used. DE 102006024591

- 38 Table 1:

<td>Product</td><td></td><td>Example 1</td><td>Comparative example</td>

<td>BET</td><td>m²/ g</td><td>142</td><td>142</td>

<td>CTAB</td><td>m²/ g</td><td>163</td><td>157</td>

<td>DBP</td><td>g / 100g</td><td>286</td><td>295</td>

<td>PH value:</td><td>-</td><td>4.3</td><td>6.0</td>

<td>Loss on drying</td><td>%</td><td>0.8</td><td>0.5</td>

<td>Loss on ignition</td><td>%</td><td>0.9</td><td>0.9</td>

<td>The ratio of SiOH extinction_isolateny</td><td></td><td>3.19</td><td>3.17</td>

<td>Density of silanol groups</td><td>SiOH / nm²</td><td>1.92</td><td>1,988</td>

<td>Modified density after whipping</td><td>g / l</td><td>23</td><td>21</td>

<td>Part of fine particles &lt;1 μm 1)</td><td>%</td><td>74,79</td><td>66.7</td>

<td>The distribution of molecules</td><td></td><td>bimodal</td><td>bimodal</td>

<td>The d90 value of the particle size distribution depends on the volume</td><td>um</td><td>5, 03</td><td>5.87</td>

<td>Behavior towards water</td><td></td><td>hydrophilic</td><td>hydrophilic</td>

<td colspan="4">1) at 5 min of ultrasound treatment at 300 Watt</td>

Example 3: Research for industrial use

3.1. Preparation of RTV-1K cross-linking silicone sealing acetate precipitated by silicic acids [0219] The amounts needed for the preparation of the following preparation are given in Table 2. During production, they are cooled with tap water so that the formulation is not heated significantly above room temperature. The production takes place at room temperature and at a relative humidity of the air from 40 to 60%.

[0220] For a planetary dissolver (from H. Linden, model LPMD 2SP) equipped with 2 1-pipe vessels with a double coil, cooling water connection and independent controlled planetary and diffuse drive, the silicone polymer is weighed out, plasticizer (silicone oil) and cross-linking substance and homogenized for 1 min at 50 min^-1 (planetary drive) and 500 min^-1 (distracting drive). The catalyst is then added and homogenized in a N 2 atmosphere for 15 min at the same rate of planetary and disperse drive. After this, in the comparative example, the stabilizer and the precipitated silicic acid, in the example according to the invention, only the precipitated silicic acid, are treated in the same way at uniformly maintained speeds. As soon as the precipitated silicic acid is completely cross-linked, it is placed in a vacuum of about 200 mbar and subjected to dispersion 10 min at 100 min^-1 planetary mixer and 2000 min^-1 dysolwera.

[0221] Immediately after the dispersion is complete, the mixer tank is vented with nitrogen. The aluminum drum (heads) is filled as quickly as possible using the drum press with the sealing compound.

- 39 3. Determination of rheological properties and storage stability of RTV-1K sealing compounds

<td colspan="3" rowspan="2">Table 2: Preparation for the preparation of a single-component cross-linking silicone mass (RTV-1K) at room temperature (acetoxy)</td><td colspan="2">42 g cross-linking substance</td><td colspan="2">30 g cross-linking substance</td>

<td colspan="2">Degree fill 12% SiO2</td><td colspan="2">Degree fill 12% SiO2</td>

<td>Hey component preparation. [Name general]</td><td>Chemical Mark</td><td>Product and manufacturer's name</td><td>Fake [g]</td><td>Participation [%]</td><td>Fake [g]</td><td>Participation [%]</td>

<td>Polymer silicone OH-terminated silicone polymer (viscosity = 50000 mPa * s)</td><td>α, ω hydroxydimetric losiloksypolidi methylsiloxane</td><td>Silopren® E 50 GE Bayer Silicones GmbH &amp; Co. KG</td><td>468,00</td><td>58.6</td><td>468,00</td><td>60.1</td>

<td>softener non-functional polydimethylsilane xan (silicone oil, viscosity = 1000 mPa * s \</td><td>α, ω trimethylsiloxy polidimetylosilo xanthan</td><td>Oil M 1000 GE Bayer Silicones GmbH &amp; Co. KG</td><td>184,50</td><td>23.1</td><td>184,50</td><td>23.7</td>

<td rowspan="2">Active extender silicic acid</td><td rowspan="2">Precipitated silicic acid</td><td>Example 1</td><td></td><td></td><td>95.79</td><td>12.3</td>

<td>Example comparative</td><td>95.79</td><td>11.99</td><td></td><td></td>

<td>Substance The crosslinking</td><td>triacetoxysilane ethyl</td><td>Triacetoxies and ethyl ether ABCR GmbH &amp; Co. KG</td><td>42,00</td><td>5.3</td><td>30.00</td><td>3.9</td>

<td>Stabilizer</td><td></td><td>TP 3556 GE Bayer Silicones GmbH &amp; Co. KG</td><td>8.00</td><td>1.0</td><td>0.00</td><td>0.0</td>

<td>Catalyst</td><td>diacetate dibutyl</td><td>TEGOKATO ® 233 Goldschmidt TIB GmbH</td><td>7 kr 0.01 g</td><td>0.001</td><td>7 kr 0.01 g</td><td>0.001</td>

<td>Total quantities</td><td></td><td></td><td>798.3</td><td>100</td><td>778.3</td><td>100</td>

cr. = drop

[0222] Produced according to example 3, section 1, "Preparation of RTV-1K silicone crosslinking silicas paste from precipitated silicas" sealing masses are stored prior to testing for at least 24 h in an air-conditioned room at 23 ° C / 50% relative humidity. .

[0223] Two tubes are stored for 35 days in an air-conditioned room at 23 ° C / 50% relative humidity for testing the sealing masses and tested at 0, 7, 14, 21, 28 and 35 days of storage respectively. In addition, two consecutive tubes are stored in a convection oven at 50 ° C for 35 days and the same is tested after 1, 7, 14, 21, 28 and 35 days of storage.

[0224] Determination of rheological properties takes place with the Haake RheoStress 1 rheometer (controlled by the PC via the RheoWin Pro program). Operation of the device and software is described in detail in the Haake manual. A 35 mm diameter piston and a MPC 35 measuring plate cap are used for the measurement. The measurement is carried out under the following conditions:

<td>The distance between the piston and the plate cap</td><td>0.5 mm</td>

<td>measuring:</td><td></td>

<td>Temperature of measurement:</td><td>23 ° C</td>

<td>Measuring range (shear rate):</td><td>0 - 10 1 / s</td>

<td>Number of measuring points:</td><td>400</td>

[0225] The measuring points are shown in a graph which on the x-axis shows the shear rate γ a on the y-axis the shear stress τ. At the shear rate = 10 1 / s, the shear stress is read and the viscosity η at 10 1 / s calculated according to η = τ / γ is calculated. Two tubes are measured, at least three measurements are made for each tube. Of the six individual results, the highest and lowest values ​​are deleted. From the remaining four results, the average value is calculated.

[0226] The Casson model is used to calculate the flow limit. The base for calculating the yield point according to Casson ranges from 0.2 to 2 1 / s with the shear rate - shear stress. The following dependency is defined:

<img file="PL2209739T3_D0003.tif" />

V 7 [0227] The value on the y-axis at which the flow curve, calculated according to Casson, intersects it is given as the flow limit according to Casson.

[0228] The determination of both the viscosity at 10 1 / s as well as the Casson flow limit is automatically made under the above-mentioned conditions using the RheoWin Pro software.

3.3 Evaluation of results [0229] To assess the durability of silicone rubber preparations incorporating the precipitated silicas of the invention, the results of flow limit measurements are used

- according to Casson and viscosity at a shear rate of 1/10 (Table 3).

[0230] By durability is meant the rheological behavior of the RTV-1K silicone sealing compound. Good durability is defined when the silicone rubber applied to the perpendicular surface is maintained there for 24 hours during curing without running off. Sufficiently good durability can be recognized by a viscosity of&gt; 100 Pas and a flow limit of&gt; 90 Pa. The values ​​for the Casson flow limit of the silicone rubber preparations of examples 3a and 3b are in a comparatively good range, even though the silicone rubber formulation 3a contains a reduced amount of stabilizing substance by 30% as well as no stabilizer. Thus, such formulations containing the precipitated silicas of the invention remain in the form in which they were applied and do not tend to run. This is also confirmed by viscosity values. Here, the precipitated silicas of the invention have clearly improved, i.e. higher viscosity, compared to the comparative examples.

[0231] Stability of storage, i.e. change in rheological properties such as yield point and viscosity as well as negative curing behavior in the tube over time are shown in Tables 4 and 5. Both storage at room temperature and at elevated temperature (50 ° C) are included C).

[0232] Tables 4 and 5 support the evidence of the low necessary amounts of crosslinker using the precipitated silicas of the invention compared to the precipitated silicas of the comparative example. The amount of cross-linking substance could be reduced by about 30%. In addition to the reduced amount of cross-linking substance equal to only 30 g per 95.79 g of precipitated silicic acid, using the precipitated silicic acid according to the invention as opposed to the comparative example, the use of a stabilizer could also be dispensed with. Thus, Table 3 shows that the viscosity of the formulation with the precipitated silicas of the invention is clearly better than the comparative example whereas the yield point in both examples is at a comparable very good level.

[0233] Despite the low amount of crosslinker and the lack of stabilizer, the formulations according to the invention with acid precipitated silicas of the invention exhibit very good storage behavior, which is also demonstrated by the viscosity stability and yield strength of 35 days stored at room temperature and 50 ° C ( Table 4 and 5) of the preparation.

[0234] In spite of the absence of the stabilizer, the trials of the invention according to the invention harden themselves after 35 days of storage time at 50 ° C in a correct manner. Precipitated silicas with high pH values ​​as shown in the comparative example require, in contrast, a stabilizer and higher amounts of cross-linking substance to cure also after prolonged storage at elevated temperatures.

- 42 Table 3: Durability test

<td>Example</td><td>Silicic acid used with</td><td>charge [%]</td><td>Content substances crosslinking [G]</td><td>Stabilizer GE TP 3556 [G]</td><td>Limit flow Casson [Pa]</td><td>Viscosity at 10 1 / s [Crimson]</td>

<td>3a</td><td>Example 1</td><td>12</td><td>30.0</td><td>0.0</td><td>241</td><td>159</td>

<td>3b</td><td>Comparative example</td><td>12</td><td>42.0</td><td>8.0</td><td>260</td><td>118</td>

Table 4: Rheology for 35 days at RT

<td>Example</td><td>adopted acid silicon with</td><td>Charging in [%]</td><td>Content substances crosslinking in ^[g^]</td><td>Stabilizer GE TP 3556 [g]</td><td>Temp. in [° C]</td><td>Duration in [d]</td><td>Viscosity at 10 1 / s [Crimson]</td><td>The limit of Casson's flow in [Pa]</td>

<td rowspan="2">3a</td><td rowspan="2">Example 1</td><td rowspan="2">12</td><td rowspan="2">thirty</td><td rowspan="2">0.0</td><td rowspan="2">23</td><td>0</td><td>159</td><td>241</td>

<td>35</td><td>163</td><td>235</td>

<td rowspan="2">3b</td><td rowspan="2">Example comparative</td><td rowspan="2">12</td><td rowspan="2">42</td><td rowspan="2">8.0</td><td rowspan="2">23</td><td>0</td><td>118</td><td>260</td>

<td>35</td><td>124</td><td>270</td>

Table 5: Rheology for 35 days at 50 ° C

<td>Example</td><td>Silicic acid used with</td><td>Naładowa not in [%]</td><td>Content substances crosslinking in [g V]</td><td>Stabilizer GE TP 3556 [G]</td><td>Temp. Toilets]</td><td>Duration in [d]</td><td>Viscosity at 10 1 / s [Crimson]</td><td>The limit of Casson's flow in [Pa]</td>

<td rowspan="2">3a</td><td rowspan="2">Example 1</td><td rowspan="2">12</td><td rowspan="2">thirty</td><td rowspan="2">0.0</td><td rowspan="2">50</td><td>0</td><td>162</td><td>259</td>

<td>35</td><td>159</td><td>300</td>

<td rowspan="2">3b</td><td rowspan="2">Example comparative</td><td rowspan="2">12</td><td rowspan="2">42</td><td rowspan="2">8.0</td><td rowspan="2">50</td><td>0</td><td>113</td><td>252</td>

<td>35</td><td>112</td><td>279</td>

List of reference marks for figures 1, 2, 2a, 3 and 3a [0235] jet mill cylindrical body grinding chamber material feed for milling grinding mill inlet

5a heating nozzles product outlet air separator air separator rotor

8a separation gap

- 43 9 inlet or inlet nozzle grinding flow heating source heating source pipe supplying insulating jacket from the temperature inlet outlet center of the grinding chamber reservoir device or manufacturing line devices outlet nozzle (diving pipe) separator body upper part of the body bottom part of the body flange peripheral circumferential collar hinge arrow body of the separator space

28a support arms cone chute flange flange cover disc cover plate shovel rotor shaft separator

35a swivel bearing upper plates machined bottom plate machined end section of the body feeder stub pipe rotary axis outlet chamber upper cover plate cover removable support arms conical annular body suction filter sieve plate material unloading pipe fines jet cone air intake spiral for classification

- 44 51 thick material output

Collar

Flange dispersion zone flange treated (chamfered) on the inner edge and replaceable liner protective tube replaceable protective tube exit / outlet of fine-grated material wreath rim

She prepared and verified

Grażyna Palka Patent attorney