Gasoline sulfur reduction in fluid catalytic cracking

【0001】

The present invention relates to reducing sulfur in gasoline and other petroleum products produced by catalytic cracking processes. The present invention provides a catalytic composition that reduces the sulfur content of a product, and a method of using this composition to reduce the sulfur content of a product.

【0002】

Catalytic cracking is an industrially applied petroleum refining process on a very large scale, especially in the United States. In the United States, most of the mixed pools of refined gasoline are produced by catalytic cracking, and almost all of them are derived from fluid cracking (FCC) processes. In the process of catalytic decomposition, the heavy hydrocarbon fraction is converted to a light product by a reaction that occurs at high temperature in the presence of a catalyst, and most of the conversion or cracking (decomposition) occurs in the gas phase. The feed feed is converted to gasoline, distillates, and other liquid cracking products, in addition to lighter gaseous cracking products consisting of 4 or less carbon atoms per molecule. The gas is partially composed of olefins and partially saturated hydrocarbons.

【0003】

During the cracking reaction, a somewhat heavy substance known as coke adheres to the catalyst. This weakens the catalytic activity and requires regeneration. After removing the adsorbed hydrocarbons from the used (or spendt) cracking catalyst, the coke is burned for regeneration and then the activity of the catalyst is restored. Therefore, the three unique steps of catalytic decomposition are: cracking, which converts hydrocarbons into lighter products, stripping, which removes hydrocarbons absorbed by the catalyst, and regeneration, which burns coke and removes it from the catalyst. Can be distinguished. The regenerated catalyst is then reused in the cracking process.

【0004】

Catalytic feed feed materials generally contain sulfur in the form of organic sulfur compounds such as mercaptans, sulfides and thiophenes. Cracking process products tend to contain significant sulfur impurities, even if half of the sulfur is converted to hydrogen sulfide during the cracking process, primarily due to catalytic decomposition of non-thiophene sulfur compounds. The distribution of sulfur in cracking products depends on multiple factors, including raw materials, catalyst types, additive presence, conversion and other operating conditions, but at least some of the sulfur is contained in light or heavy gasoline fractions. It is also included in the product pool. As the environmental regulations applicable to petroleum products become stricter, for example, in the Reformulated Gasoline (RFG) regulation, the emission of sulfur oxides and other sulfur compounds into the air after the combustion process The sulfur content of the product was generally reduced in response to concerns about.

【0005】

Attempts have been made to remove sulfur from the FCC feed by hydrogenation before cracking begins. Although very effective, this attempt tends to be costly in terms of operation and capital investment due to the high hydrogen consumption. Another attempt has been made to remove sulfur from the decomposed product by hydrogen treatment. This is also very effective, but this method has the disadvantage that when high octane olefins are saturated, the valuable product octane is lost.

【0006】

From an economic point of view, it is desirable to remove sulfur in the cracking process itself. This is because it effectively desulfurizes the main components of the gasoline blend pool without any additional treatment. Various catalytic materials have been developed to remove sulfur during the FCC process cycle, but so far most developments have focused on removing sulfur from the flue gas of the regeneration tower. .. An early attempt by Chevron was to use an alumina compound as an additive in the inventory of cracking catalysts (or load or retention) and adsorb sulfur oxides in the FCC regeneration tower; in the feed. The adsorbed sulfur compounds involved in the process are released as hydrogen sulfide during cycle cracking and sent to the product recovery section of the unit where they are removed. "Additives Improve FCC Process" by Krishna et al. (Hydrocarbon Processing), November 1991, pp. 59-66). Sulfur is removed from the flue gas from the regeneration tower, but the sulfur concentration in the product is not significantly affected, if any.

【0007】

Another technique for removing sulfur dioxide from the regeneration tower is based on the use of magnesium-aluminum spinel as an additive to the circulating catalyst inventory (or loading catalyst) in the FCCU. The technology has achieved remarkable commercial success in the name of DESOX®, which is used as an additive in this process. Representative patents for this type of sulfur removal additive include US Pat. Nos. 4,963,520, 4,957,892, 4,957,718; 4,790,982 and the like. However, the sulfur concentration of the product does not decrease so much.

【0008】

Catalytic additives that reduce the sulfur concentration of liquid cracking products have been proposed by Wormsbecher and Kim in US Pat. Nos. 5,376,608 and 5,525,210. It uses an alumina-supported Lewis acid cracking catalytic additive to produce sulfur-reduced gasoline, but the system has not been significantly commercially successful. Therefore, effective additives have long been needed to reduce the sulfur content of liquid cracking products.

【0009】

Therefore, we have developed catalyst-added materials for catalytic cracking processes that can reduce the sulfur content of liquid products in cracking processes. It is possible to reduce sulfur in the cracking fraction of gasoline and other fractions, including intermediate distillates obtained from light cycle oils.

【0010】

The sulfur-reducing catalysts of the present invention are usually in a circulating cracking catalyst inventory, which is a normally matrixed zeolite based on faujasite zeolite (usually Zeolite Y), in combination with an active cracking catalyst in a cracking unit. It is used in combination with the main component of. The sulfur reduction catalyst may be used as an independent granular additive used in combination with a cracking catalyst or as a component incorporated into the catalyst.

【0011】

According to the present invention, the sulfur removing composition comprises a porous molecular sheave containing a metal in an oxidized state greater than 0 within the pore (or pore) structure of the sheave. Molecular sieves are most often zeolites, which match zeolites with features that match large pore zeolites such as zeolite beta or zeolite USY, or intermediate pore size zeolites such as ZSM-5. It may be a zeolite having the characteristics of Non-zeolite molecular sieves such as MeAPO-5 and MeAPSO-5, and mesoporous crystalline materials such as MCM-41. material) may be used as the sheave component of the catalyst. Metals such as vanadium, zinc, iron, cobalt and gallium are effective. Metal-containing sheaves or zeolites are used in combination with active catalytic cracking catalysts (usually forjasites such as Zeolite Y) to process hydrocarbon feed feedstocks in fluid cracking (FCC) units, and low sulfur Manufactures gasoline and other liquid products, such as light cycle oils that can be used as low-sulite diesel blend components or fuel oils.

【0012】

The exact mechanism by which metal-containing zeolites remove the sulfur components normally present in cracked hydrocarbon products is unknown, but it makes the organic sulfur compounds in the feed inorganic sulfur so that the process is a true catalytic process. Accompanied by conversion to a compound. In this process, zeolites or other molecular sheaves are thought to alter the dimensions of the pores to provide shape selectivity, and metal sites in zeolites provide adsorption sites for sulfur seeds (spicies). Therefore, we have named our process "shape-selective desulfurization".

【0013】

FCC Process The sulfur removal catalyst of the present invention is used as a catalytic component of the catalytic cracking inventory in catalytic cracking processes, which are nowadays most often fluid cracking (FCC) processes. For convenience, the present invention will be described with reference to the FCC process, but the additives of the present invention are older moving bed type (TCC) decomposition processes in which the particle size is appropriately adjusted to suit the requirements of the process. Can also be used in. Except for the addition of the additives of the invention to the inventory of catalysts and some possible changes in the product recovery section, the method of performing the process remains unchanged, as described below. Therefore, an original report by conventional FCC catalysts, such as Venuto and Habib, "Fluid Catalytic Cracking with Zeolite Catalysts" (Marcel Dekker); New York 1979 International Standard Book Number (ISBN) 0-8247-6870-1), and also, for example, Sadeghbeigi's "Fluid Catalytic Cracking Handbook" (Gulf publ. Co) Houston 1995 ISBN 0-88415- Zeolite-based catalysts with faujasite cracking components, as described in many other sources such as 290-1), may be used.

【0014】

To put it a little briefly, the fluidized catalytic cracking process, in which heavy hydrocarbon feeds containing organosulfur compounds are decomposed into lighter products, is in the recirculation cracking process of circulating catalysts, with dimensions ranging from 20 to 100 microns. It is caused by the contact between a circulating fluidable cracking catalyst inventory and a feed. An important step in the cyclic process is: (i) The feed is operated under catalytic cracking conditions in the catalytic cracking zone, usually the cracking zone of the riser, to bring the feed into contact with the source of the regenerated hot cracking catalyst. Crack cracking by producing cracks containing used (or spent) catalysts containing coke and removable hydrocarbons as well as cracked products; (ii) cracks, usually 1 or In multiple cyclones, the cracked product-rich gas phase and the solid-rich phase containing waste catalyst are separated; (iii) the gas phase is removed as a product and rectified in the main tower of FCC and its associated auxiliary tower. And form a liquid cracking product containing gasoline; (iv) To remove occluded hydrocarbons from the catalyst, the used catalyst is usually stripped with steam and then the stripped catalyst is oxidized. The process is to regenerate at a high temperature to produce a regenerated catalyst, and then recycle the regenerated catalyst into a cracking zone to crack a larger amount of feed.

【0015】

The feed to the FCC process is a high boiling point feed starting from mineral oil, typically at least 290 ° C (550 ° F) and often above the initial distillate of 315 ° C (600 ° F). Is a feed with. The cut point for most refinery FCC feeds is at least 345 ° C (650 ° F). The end point depends on the characteristics of the feed or the operating characteristics of the refinery. The feed may generally be a distillate having an end point of 550 ° C (1020 ° F) or higher, for example 590 ° C (1095 ° F) or 620 ° C (1150 ° F). Alternatively, a residual oil material (which cannot be distilled) may be included in the feed, which may include all or most of the feed. Distillable feeds include straight-run feeds such as gas oil, for example heavy or light atmospheric pressure light oil, heavy or light decompressed gas oil, and light coker gas oil (coke gas). Includes cracked feeds such as oil; or coker light oil), heavy coker gas oil. Hydrogenated feeds may be used, for example hydrogenated gas oil, especially hydrogenated heavy oil, as the catalysts of the present invention can result in a significant reduction in sulfur. The first hydrogen treatment aimed at reducing sulfur can be eliminated, albeit with improved degradability.

【0016】

By performing catalytic decomposition in the presence of a sulfur-reducing catalyst in the process of the present invention, the sulfur content of the gasoline portion of the liquid cracking product is effectively reduced to a more acceptable level.

【0017】

The sulfur reduction catalyst of the present invention may be used in the form of an independent granular additive added to the cracking main catalyst in the FCCU, or the sulfur reduction catalyst is included and integrated as an additional component of the cracking catalyst. A cracking / sulfur reduction catalyst system may be provided. Cracking catalysts are usually based on the active cracking component of faujasite zeolite, which is, for example, calcined rare-earth exchanged type Y. recently (CREY) (the method of manufacture thereof is disclosed in U.S. Pat. No. 3,402,996), such as the ultrastable Y zeolite (USY) disclosed in U.S. Pat. No. 3,293,192, and, for example, U.S. Pat. Conventional zeolite Y in one form among the various partially exchanged types of Y zeolite-like forms disclosed in 3,607,043 and 3,676,368. The active cracking component is conventional with matrix materials such as alumina to provide certain mechanical properties (such as abrasion resistance) and to control the activity of one or more highly active zeolite components. Combined with. The particle size of cracking catalysts is generally in the range of 10-100 microns for effective fluidization. When used as a separate granular additive, the sulfur reduction catalyst (and all other additives) has a particle size commensurate with the particle size of the cracking catalyst to avoid separation of components during the cracking cycle. Is usually selected to have.

【0018】

Sheave Component According to the present invention, the sulfur removal catalyst comprises a porous molecular sheave containing a metal in an oxidation state higher than 0 within the pore structure of the sheave. Molecular sieves are often zeolites, which can be large pore zeolites such as zeolite beta, or zeolites with the same properties as medium pore size zeolites such as ZSM-5, and fall into the latter category. What is preferred.

【0019】

As described above, the component of the molecular sheave of the sulfur reduction catalyst of the present invention may be a zeolite sheave or a non-zeolite sheave. When used, zeolites may be selected from zeolites with large pore size or medium small pore size (Frilette et al., J. Catalysis 67,218-222 (1981). "Shape Selective Catalysis in Industrial Applications" by Chen et al., Marcel Deckker, New York 1989, discussing the classification of zeolites by small pore size based on a general outline. Year ISBN See 0-8247-7856-1). Zeolites with small pore size, such as zeolite A and erionite, are generally unfavorable due to their molecular size exclusion properties, in addition to their inadequate stability for use in catalytic cracking processes. This molecular size exclusion property tends to exclude many components of the cracked product as well as components of the cracking feed. However, the small pore size of the sheave was found to be as effective for both medium and large small pore size zeolites as mesoporous crystalline materials such as MCM-41, as shown below. Therefore, it is clearly not important.

【0020】

Zeolites with properties consistent with the presence of large pore (12-membered ring) structures may be used to form the sulfur-reducing catalysts of the present invention, such zeolites include Y, REY, CREY, USY (this Of these, various forms of zeolite Y, such as (preferably the last one), as well as other zeolites such as zeolite L, zeolite beta, mordenite containing dealuminated mordenite, and zeolite ZSM-18. In general, large pore size zeolites are characterized by a small pore structure with an annular opening of at least 0.7 nm, while medium or intermediate small pore size zeolites are smaller than 0.7 nm but larger than 0.56 nm. Will have a hole opening. Suitable intermediate small pore size zeolites that may be used are ZSM-5, ZSM-22, ZSM-23, ZSM-35, ZSM-50, ZSM-57, MCM-22, MCM-49, MCM-56. Includes pentasil zeolite such as. These are already known materials. Zeolites may be used with skeletal metal elements other than aluminum, such as boron, gallium, iron and chromium.

【0021】

The use of zeolite USY is particularly preferred. This is because the zeolite is commonly used as an active cracking component of cracking catalysts, thus allowing the sulfur reduction catalyst to be used in the form of an integrated cracking / sulfur reduction catalyst. The USY zeolite used as a cracking component is also advantageously used as a sheave component for independent granular addition catalysts. Stability correlates with the small unit cell size of the USY, and for optimal results the UCS should be 2.420-2.455 nm, preferably 2.425-2.450 nm, 2.435-2.440. nm is a very good range.

【0022】

In addition to zeolites, other molecular sheaves may be used, as it is clear that some acidic activity (conventionally measured by alpha values) is required for maximum performance. It cannot work in an advantageous way. Test data show that alpha values greater than 10 (metal-free sheaves) are suitable for suitable desulfurization activity, and alpha values typically in the range 0.2-2,000 are suitable. Alpha values from 0.2 to 300 correspond to the normal range of acidic activity of these additives.

【0023】

Typical non-zeolite sheave materials that can provide suitable supporting components for the metal components of the sulfur reduction catalysts of the present invention include silicates of various silica-alumina ratios (eg, metal silicates and titanium silicates). ), Metaliluminates (eg germanium aluminate), metal phosphates, metal-integrated aluminophosphates (MeAPO and ELAPO), metal-integrated silicoaluminophosphates (MeAPSO and ELAPSO), Includes aluminophosphates such as silico and metallic aluminophosphates called silicoaluminophosphates (SAPO), gallogerminates and combinations thereof. A discussion of the structural relationships between SAPO, AlPO, MeAPO and MeAPSO is from Stud. Surf. Catal. 37 Found in several sources, including 13-27 (1987). AlPO contains aluminim and phosphorus, while in SAPO some phosphorus and / or both some phosphorus and aluminum are replaced by silicon. In MeAPO, various metals such as Li, B, Be, Mg, Ti, Mn, Fe, Co, An, Ga, Ge, and As are present in addition to aluminum and phosphorus, while MeAPSO is further silicon. including. Me_aAl_{b b}P_cSi_dO_eThe negative charge of the lattice (lattice) is offset by the cations, where Me is magnesium, manganese, cobalt, iron, and / or zinc. Me_xAPSO is described in US Pat. No. 4,793,984. SAPO-type sheave materials are described in US Pat. No. 4,440,871. MeAPO-type catalysts are described in US Pat. Nos. 4,544,143 and 4,567,029. ELAPO catalysts are described in US Pat. No. 4,500,651 and ELAPSO catalysts are described in European Patent Application No. 159,624. Certain molecular sheaves, for example, have the following patents: MgAPSO or MAPSO is US Pat. No. 4,758,419; MnAPSO is US Pat. No. 4,686,092; CoAPSO is US Pat. No. 4,744,970; FeAPSO is US Pat. No. 4,744,970. 4,683,217; and ZnAPSO are described in US Pat. No. 4,935,216. Specific silicoaluminophosphates that may be used include SAPO-11, SAPO-17, SAPO-34, SAPO-37. Other specific sheave materials include MeAPO-5, MeAPSO-5.

【0024】

Another class of crystalline supporting materials that can be used is the group of mesoporous crystalline materials exemplified by the MCM-41 and MCM-48 materials. These mesoporous crystalline materials are described in US Pat. Nos. 5,098,684, 5,102,643, and 5,198,203. MCM-41 is described in U.S. Pat. No. 5,098,684 by a microstructure with a uniform, hexagonal (or hexagonal) arrangement of small pores with a diameter of at least 1.3 nm. Characterized. After firing, it corresponds to an X-ray diffraction pattern with at least one d-spacing greater than 1.8 nm, and a d100 value greater than 1.8 nm, which corresponds to the d-spacing of peaks in the X-ray diffraction pattern. ) Is shown as a hexagonal electron diffraction pattern. The preferred catalytic form of this material is an aluminosilicate, but other metal silicates may also be used. MCM-48 has a cubic (or cubic) structure and is manufactured by a similar manufacturing procedure.

【0025】

Metal component The metal component is incorporated into the molecular sheave support material to form the additive of the present invention. To be effective, one or more metals should be present inside the pore structure of the sheave component. Zeolites containing metals and other molecular sheaves preferably include (1) post-addition of the metal to the sheave or catalyst containing one or more sheaves, and (2) one or more metal atoms in the backbone structure. It can be produced by synthesizing sheaves and (3) synthesizing one or more sheaves with large metal ions trapped in the small pores of zeolite. After adding the metal component, it is necessary to carry out washing, drying and calcination to remove unbound ionic species. These techniques are known in their own right. Post-addition of metal ions is preferred from the standpoint of convenience and economy, allowing the available sheave material to be converted and used in the additives of the present invention. A wide variety of methods of post-adding metals can be used to produce the catalysts of the invention, such as aqueous exchange of metal ions, exchange of solid phase states with salts of one or more metal halides. , Immersion of metal salts in solution, and metal deposition can be used. However, in any case, it is important that the addition of one or more metals allows the metal component to enter the pore structure of the sheave component.

【0026】

When the metal is present as an exchanged cation species in the pores of the sheave component, the hydrogen transfer (or transfer) activity of the metal component is such that for the preferred metal component, the hydrogen transfer reaction that occurs during the cracking process is usually acceptable. It was found to reduce to a point where it was maintained at a low level. Therefore, coke and light gas increase slightly during cracking, but they remain within acceptable limits. The unsaturated light end (or light end) can be used at least as an alkylating feed and is thus recycled into the gasoline pool, thus providing a gasoline range of hydrocarbons resulting from the use of the additives of the present invention. Loss is not so great.

【0027】

Due to concerns that excess coke and hydrogen are produced during the cracking process, the metals incorporated in the additives should not exhibit significant hydrogenation activity. For this reason, noble metals such as platinum and palladium with strong hydrogenation-dehydrogenation function are not preferred. Combinations of base metals and base metals with strong hydrogenating functions, such as nickel, molybdenum, nickel-tungsten, cobalt-molybdenum, and nickel-molybdenum, are not preferred for similar reasons. Preferred base metals are metals of the 3rd period, 5th, 8th, 9th and 12th groups (IUPAC classification, formerly 2B, 5B and 8B groups) of the periodic table. Vanadium, zinc, iron, cobalt and gallium are effective with the preferred metal component vanadium. It is surprising that vanadium can be used in this way in FCC catalyst compositions. This is because vanadium is usually thought to have a very significant effect on zeolite cracking catalysts, and much effort has been made to develop vanadium inhibitors. For example, "Vanadium Poisoning of Cracking Catalyst: Mechanism of Poisoning and Design of Vanadium Tolerant Catalyst System" by Wormsbecher et al. (Vanadium Poisoning of Cracking Catalyst: Mechanism of Poisoning and Design of Vanadium Tolerant Catalyst System) See J. Catalysis 100, 130-137 (1986)). The location of vanadium within the pore structure of the sheave is thought to fix vanadium and prevent it from becoming a vanadate species that can be harmfully bound to the sheave component;

【0028】

Vanadium is particularly suitable for reducing sulfur in gasoline, especially when supported by zeolite USY. The yield structure of the V / USY sulfur reduction catalyst is of particular interest. While other zeolites are performing sulfur reduction in gasoline after the metal has been added, they C the gasoline.₃And C₄Converts to gas. Converted C₃= And C₄Although much of the = can be alkylated and returned to the petrol pool and reblended, C₄-High yields of moist gas can be problematic. This is because many refiners are limited by the capacity of their wet gas compressors. USYs containing metals have a yield structure similar to current FCC catalysts. This advantage allows the content of V / USY zeolite in the catalyst mixture to be adjusted to the desired desulfurization level without being limited by the constraints of the FCC unit. Therefore, vanadium in the Y zeolite catalyst, along with zeolite represented by USY, is particularly preferred for reducing gasoline sulfur in FCC. USYs found to give particularly good results are USYs with small unit cell sizes in the range of 2.435 to 2.450 nm and correspondingly small alpha values. Base metals such as vanadium / zinc are also preferred in terms of overall sulfur reduction.

【0029】

Generally, the most convenient method of using a sulfur-reducing catalyst is to use it as an independent granular additive to the catalyst inventory. When used in this way, it may be used in the form of pure sheave crystals and may be pelleted to the proper dimensions (without matrix) for use in the FCC, but metal-containing sheaves are sufficiently fluid. It is usually matrixed to obtain sufficient particle abrasion resistance so as to maintain the formation. Conventional cracking catalyst matrix materials such as alumina or silica-alumina, along with the clay usually added, are suitable for this purpose. The amount of matrix relative to the sheave may typically be between 20:80 and 80:20 on a weight basis. Conventional matrixing techniques may be used.

【0030】

Instead of using independent granular additives, the sulfur reduction catalyst may be incorporated into the cracking catalyst to form an integrated FCC cracking / gasoline sulfur reduction catalyst. Zeolite USY, which is useful as a cracking catalyst component, has been found to provide good product sulfur-reducing activity, so the metal component is used as a cracking catalyst by ensuring that the metal enters the sheave, that is, the internal pore structure of the USY zeolite. It is convenient to incorporate. This involves recalcining the USY cracking catalyst to ensure a small unit cell size, and then ion exchange of the metal (eg vanadium) or cation exchange so that the metal ions can be immobilized in the small pore structure of the zeolite. It can be done appropriately by immersing under conditions that allow it to occur. In this case, the immersion / replacement process should be carried out with a controlled amount of metal so that the required number of sites can be left on the sheave to catalyze the cracking reaction. Alternatively, the metal can be incorporated into a sheave component, such as USY zeolite or ZSM-5, after the calcining required to remove the organic matter from the synthesis. The metal-containing components can then be formulated to the final catalyst composition by cracking, addition of matrix components and spray drying of the formulation to form the final catalyst. The amount of sulfur-reducing component is generally up to 25% by weight of the total catalyst. This amount corresponds to an amount that may be used as an independent granular additive, as described below.

【0031】

The amount of the metal component in the sulfur reduction addition catalyst is usually 0.2 to 5% by weight (as a metal, relative to the weight of the sheave component), generally 0.5 to 5% by weight, but an amount outside this range, for example, It will be found that even 0.10 to 10% by weight still provides some sulfur removal effect. When the sulfur reduction catalyst is used in the form of an integrated cracking / sulfur reduction catalyst, the amount of metal somewhat reflects the dual functionality of the system, in fact the dual functionality of the formulation. It is low and the range of metal content generally ranges from 0.1 to 5% by weight of the total catalyst, more generally from 0.2 to 2% by weight.

【0032】

Use of Sulfur Reduction Catalyst When the catalyst is formulated as an integrated catalyst system, the active cracking component of the catalyst is added to the sulfur reduction system for ease of manufacture and to maintain controlled cracking properties. It is preferable to use it as a sheave component, and it is particularly preferable to use zeolite USY. However, it is possible to incorporate another active cracking sheave material, such as Zeolite ZSM-5, into an integrated catalyst, such systems that have the properties of a second active sheave material, such as ZSM-5. Useful when needed. In both cases, the impregnation / replacement process is carried out with a controlled amount of metal, so that the required number of sites are left in the sheave and either the active cracking component or the present. Allow the cracking component of 2 (eg ZSM-5) to catalyze the required cracking reaction.

【0033】

Use of Sulfur-Reduced Catalyst Composition A convenient method of using a sulfur-reduced catalyst is to use it as an independent granular additive to the catalyst inventory. In a preferred embodiment, adding a catalytic additive to the entire catalytic inventory of the unit, along with the sieve material Zeolite USY, does not significantly reduce overall cracking due to the cracking activity of the USY zeolite. The same is true when another active cracking material is used as a sheave component. When used in this way, the composition may be used in the form of pure sheave crystals pelleted to the proper dimensions (without matrix, with the addition of metallic components) for use in the FCC. .. However, metal-containing sheaves are usually matrixed to obtain adequate particle abrasion resistance and to maintain sufficient fluidity. Conventional cracking catalyst matrix materials, such as alumina or silica-alumina, are suitable for this purpose, along with the clay normally added. The amount of matric to sheave is usually 20: 80-80: 20 on a weight basis. Conventional matrixing techniques may be used.

【0034】

Use as an independent granular catalyst additive allows the ratio of sulfur reduction and cracking catalyst components to be optimized based on the amount of sulfur in the feed and the desired degree of desulfurization: used in this way. If so, it is used in an amount of 1-50% by weight of the total catalyst inventory in the FCCU; in most cases, that amount is 5-25% by weight, eg 5-15% by weight. 10% represents the most practical standard. Additives may be added by conventional methods, may be added to the regeneration tower with a make-up catalyst, or may be added by other convenient methods. Additives maintain sulfur-removing activity over a long period of time, even though very high concentrations of sulfur feed will reduce sulfur-removing activity in a short period of time.

【0035】

Instead of using independent granular additives, there is a method of using a sulfur reduction catalyst incorporated into a cracking catalyst to form an integrated FCC cracking / gasoline sulfur reduction catalyst. If the sulfur-reducing metal component is used in combination with a sheave other than the active cracking component, eg ZSM-5 or zeolite beta when the main active cracking component is USY, the sulfur-reducing component (adding metal to the sheave) Is generally 25% by weight or less of the total catalyst, corresponding to the amount when used as an independent granular additive as described above. However, the presence of the metal component does not significantly reduce the cracking activity, and thus the cracking / sulfur reduction catalyst integrated by adding the metal component to the active cracking component of the cracking catalyst (eg USY). It is possible to formulate the system. The concentration of metal components added is adjusted according to the treatment required to maintain a predetermined balance between cracking activity and sulfur reducing activity.

【0036】

Other components that are active as catalysts may be present in the circulating inventory of catalytic materials, in addition to cracking catalysts and sulfur removal additives. Examples of such other materials include zeolite ZSM-5-based octane-enhancing catalysts, supported noble metals (eg platinum) -based CO combustion accelerators, DESOX (trade name) (magnesium-aluminum spinel). ) Includes flue gas desulfurization additives, vanadium trapping agents, and bottom cracking additives, such as those in Krishna, Sadeghbeigi, op. Cit., And Scherzer. These components are described in "Octane Enhancing Zeolitic FCC Catalysts" (Marcel Dekker; New York 1990 International Standard Book Number (ISBN) 0-8247-8399-9). , They may be used in their normal usage.

【0037】

The effect of the additives of the present invention is to reduce the sulfur content of liquid cracking products, especially light and heavy gasoline fractions, but the reduction of sulfur content is also observed in light cycle oils, which can be used for diesel or household use. It shall be more suitable for use as a blend component of fuel oil. Sulfur removed by the use of catalysts is converted to inorganic form and released as hydrogen sulfide, which is recovered by the usual method in the product recovery section of the FCCU, similar to the hydrogen sulfide normally released in the cracking process. Will be done. Increased amounts (or loadings) of hydrogen sulfide may require additional sour gas / water treatment, but these are unlikely to be limiting due to the significant reduction in sulfur in gasoline. There will be.

【0038】

The amount of sulfur reduction in gasoline is considerably increased by using the catalyst of the present invention, and by using the preferred form of the catalyst described above, it is basic to use a conventional cracking catalyst at a constant conversion rate. In some cases, it is reduced to 75%. As shown in the following examples, gasoline sulfur can be easily reduced by 25% with various additives according to the present invention. The amount of sulfur reduction depends on the amount of organic sulfur compounds initially contained in the cracking feed, with the highest reduction for feeds with higher sulfur content. The metal content of the equilibrium catalyst in the unit also affects the degree of desulfurization achieved, the lower the metal content in the equilibrium catalyst, especially the vanadium content, the greater the degree of desulfurization. As shown in Table 17 below, the catalysts of the present invention are still effective when the vanadium content is fairly high, but desulfurization is very effective when the vanadium content of the E-catalyst is less than 1000 ppm. Sulfur reduction not only improves the quality of the product, but also yields the product if the cracked gasoline end point (or end point) of the refinery is limited by the sulfur content of the heavy gasoline fraction. It is also effective for increasing the rate. By providing an effective and economical way to reduce the sulfur content of heavy gasoline fractions, gasoline endpoints are widened without the need to rely on expensive hydrogen treatment, resulting in a refinery economy. It has a positive effect. If later hydrogen treatment is planned, it is also preferable to remove various thiophene derivatives that are difficult to remove by hydrogen treatment under less severe conditions.

【0039】

[Example]

Examples 1 to 7 describe the production of zeolite containing a metal. Example 1: Production of Zeolite Replaced with Zinc As shown in Table 1, the size of the pores is changed to Zn.²⁺A series of zeolites exchanged in was produced. First, SiO₂/ Al₂O₃ZSM-5, SiO with a ratio of 26/1₂/ Al₂O₃MCM-49, SiO with a ratio of 19/1₂/ Al₂O₃Beta with a ratio of 35/1, and MCM-41 containing silica were prepared by ammonium exchange and calcination to form a hydrogen form. Bulk SiO₂/ Al₂O₃A small unit cell size USY (CBV600 USY, UCS2.438nm) with a ratio of 5.4 was obtained from PQ and used untreated. Zinc, ZnCl₂It was added to the H-type zeolite by aqueous exchange using a solution. Zeolites exchanged with Zn are added to the cleaning solution as Cl.^-It was washed until it was no longer contained, and all unbound ion species were removed. The zeolite was then dried and calcined in an air stream at 540 ° C for 3 hours. The amount of Zn filled in the pores of zeolite varied between 0.9% Zn and 8.3% Zn. Table 1 summarizes the physical properties of Zn / zeolite.

【0040】

[table 1]

Physical Properties of Zinc / Zeolite Examples<img he="95" id="000002" wi="154" file="2_0003545652.tif" img-format="tif" img-content="drawing" /> 【0041】

Example 2: Production of Vanadium-Replaced Zeolites As shown in Table 2, a series of vanadium-replaced zeolites were produced by varying the size of the pores. The production procedure was the same as that of Example 1 except that vanadyl sulfate was used for vanadium exchange. The amount of vanadium filled in the zeolite varies over the range of 0.1 to 1.1 wt% V.

【0042】

The oxidation state of V in V / USY was evaluated using X-ray photoelectron spectroscopy (XPS). The binding energies measured for untreated and steamed (or steamed) V / USY are the reference sample V.₂O₄And V₂O₅It was close to that of. XPS results suggest that vanadium species in V / USY have an oxidation number (or state of oxidation) in the range IV-V. When it is fully oxidized, the oxidation state is V⁵⁺Approaching. Propylene / N at high temperature₂When reduced using a gas stream, the oxidation state is V⁴⁺(Discussing XPS on Catalytic Properties, IM Campbell, "Catalysis at Surfaces, Chapter 4.4.4, Chapman and Hall" ) Company; New York See 1988).

【0043】

[Table 2]

Physical Properties of Vanadium / Zeolite Examples<img he="95" id="000003" wi="154" file="3_0003545652.tif" img-format="tif" img-content="drawing" /> 【0044】

Example 3: Production of Iron-Replaced Zeolites As shown in Table 3, a series of iron-replaced zeolites were produced by varying the size of the pores. SiO₂/ Al₂O₃ZSM-5, SiO with a ratio of 26/1₂/ Al₂O₃MCM-49, SiO with a ratio of 19/1₂/ Al₂O₃Beta with a ratio of 35/1, and bulk SiO₂/ Al₂O₃A small unit cell size USY (CBV600 USY, UCS 24.38 Å) with a ratio of 5.4 was used. The manufacturing procedure was the same as that of Example 1 except that iron (III) chloride was used for iron exchange. The amount of Fe filled in zeolite varies widely in the range of 0.6 to 3.5% by weight Fe. All the exchanged zeolites show that the surface area and crystallinity of the zeolite are well maintained even after steam deactivation.

【0045】

[Table 3]

Physical Properties of Iron / Zeolite Examples<img he="86" id="000004" wi="154" file="4_0003545652.tif" img-format="tif" img-content="drawing" /> 【0046】

Example 4: Production of Cobalt-Substituted Zeolites As shown in Table 4, a series of zeolites solid-phase exchanged with cobalt were produced by changing the size of the pores. The procedure for the exchange process was based on the experiment published by Li et al. In "Applied Catalysis A" (150, 1997, pp. 231 to 242). 26 / 1m²g^-1Ratio of ZSM-5, SiO₂/ Al₂O₃ZSM-5, SiO containing silicon with a ratio of 450/1₂/ Al₂O₃Beta, bulk SiO with a ratio of 35/1₂/ Al₂O₃USY with a ratio of 5.4 (Grace's Z14 USY, UCS 24.52 Å), and MCM-41 containing silicon were used. CoCl obtained from Aldrich₃ 6H₂Finely grind O (28.2g) and SiO₂/ Al₂O₃It was mixed with ZSM-5 crystals (50 g) having a ratio of 26/1 and then the mixture was lightly ground together. CoCl₃ 6H₂The weight of O corresponds to a molar ratio of Co to ZSM-5 Al content of 2: 1. The mixture was placed in a ceramic dish with a pan and fired at 370 ° C for 6 hours in the atmosphere. The calcined product is placed in DI (deionized) water, left to stand for 10 minutes, filtered, and washed with DI water to clear the solution.^-Was washed until it was no longer contained. The filter cake was then dried and baked in the air at 540 ° C for 3 hours. The production procedure for other zeolites is the same as the production procedure for Co / ZSM-5, except that the molar ratio of Co: Al for USY is 0.5: 1 and excess Co is used for zeolite containing silicon. Met. The Co filled in the zeolite is in the range of 1.5 to 3.2% by weight. All the exchanged zeolites show that the surface area and crystallinity of the zeolite are well preserved after steam deactivation.

【0047】

[Table 4]

Physical Properties of Cobalt / Zeolite Examples<img he="95" id="000005" wi="154" file="5_0003545652.tif" img-format="tif" img-content="drawing" /> 【0048】

Example 5: Production of gallium-replaced zeolite As shown in Table 5, a series of gallium-replaced zeolites were produced by varying the size of the pores. SiO₂/ Al₂O₃ZSM-5, SiO with a ratio of 26/1₂/ Al₂O₃MCM-49, SiO with a ratio of 19/1₂/ Al₂O₃Beta with a ratio of 35/1, and bulk SiO₂/ Al₂O₃A small unit cell size USY with a ratio of 5.4 (Grace Z14 USY, UCS 2.452 nm) was used. The manufacturing procedure was the same as that of Example 1 except that gallium (III) nitrate was used for gallium exchange. The amount of Ga filled in the zeolite varies over the range of 0.7 to 5.6 wt% Ga. All the exchanged zeolites show that the surface area and crystallinity of the zeolite are well preserved after steam deactivation.

【0049】

[Table 5]

Physical Properties of Gallium / Zeolite Examples<img he="86" id="000006" wi="154" file="6_0003545652.tif" img-format="tif" img-content="drawing" /> 【0050】

Example 6: Production of ZSM-5 Zeolite Containing Skeleton Fe A sample of [Fe] ZSM-5 zeolite with varying skeleton Fe content was first calcined under nitrogen at 480 ° C for 3 hours. N₂[Fe] ZSM-samples fired in 1M were exchanged with 1M ammonium acetate solution (10cc per 1g of zeolite) at 65 ° C for 1 hour, filtered, and washed with deionized water. Ammonium exchange was repeated once more, then the filter cake was dried and baked in air at 540 ° C for 6 hours. Table 6 summarizes the physical properties of the H-type [Fe] ZSM-5 sample. All the exchanged zeolites show that the surface area and crystallinity of the zeolite are well preserved after steam deactivation.

【0051】

[Table 6]

Physical Properties of Iron / Zeolite Examples<img he="86" id="000007" wi="154" file="7_0003545652.tif" img-format="tif" img-content="drawing" /> 【0052】

Example 7: MeAPO containing skeletal metal AlPO-11 and AlPO-5 containing molecular sheave metal were obtained from UOP (MeAPO). They were steamed in 100% steam at 815 ° C for 4 hours prior to evaluation. The physical properties shown in Table 7 indicate that FeAPO-5 and ZnAPO-5 have better hydrothermal stability than FeAPO-11 and MnAPO-5.

【0053】

[Table 7]

Physical Properties of MeAPO Molecular Sheaves<img he="78" id="000008" wi="154" file="8_0003545652.tif" img-format="tif" img-content="drawing" /> 【0054】

Example 8: Production of vanadium / alumina and zinc / alumina catalysts In this example, in order to show the characteristics of the metal / zeolite system, a catalyst was produced as a reference case and compared with an alumina catalyst impregnated with vanadium (described later). See Example 16).

【0055】

1.V / Al₂O₃Preparation of catalyst Amorphous alumina of pseudoboehmite (or pseudoboehmite) was spray-dried with an aqueous slurry of alumina to obtain fluid catalyst particles. Spray dried Al₂O₃Particles are 200m²g^-1It had a surface area of. This was impregnated with vanadium using a solution containing vanadium oxalate so that the vanadium content was 1% by weight. Vanadium oxalate solution (6 wt% V) contains 15 g oxalic acid and 9.5 g V₂O₅70g of H deionized₂Made by heating in O. The mixture is all V₂O₅Reacted and heated until dissolved. Additional H to the resulting solution of vanadium₂O was added to make the whole solution 100 g. 8.3 g of 6% vanadium solution H₂Dilute to 48 ml with O and spray dry Al₂O₃The particles (99 g on a dry basis) were impregnated to fill the small pores of the catalyst. The material was then dried at 100 ° C. for 2 hours.

【0056】

2. Zn / Al₂O₃Catalyst production 200m²g^-1Spray-dried Al with a surface area of₂O₃To Zn (NO)₃)₂Zn was impregnated with the solution so that the Zn content was 10% by weight. 87.5g Al₂O₃(Dry amount standard), 45.5g Zn (NO)₃)₂ 6H₂O is enough H₂It was impregnated with 49 ml of solution dissolved in O. The material was dried at 100 ° C for 2 hours and then calcined at 650 ° C for 2 hours.

【0057】

[Table 8]

V / Al₂O₃And Zn / Al₂O₃Physical properties of additives<img he="44" id="000009" wi="154" file="9_0003545652.tif" img-format="tif" img-content="drawing" /> 【0058】

The following examples, ie, Examples 9-15, show an improved catalytic cracking process using the sulfur removing additives of the present invention.

【0059】

Example 9: Evaluation of fluid catalytic cracking of zinc-exchanged zeolite The Zn / zeolite of Example 1 was pelleted to a size such that the average particle size was about 7 micrometers (T), and then a muffle furnace. It was steam-treated at 815 ° C for 4 hours to mimic the catalytic deactivation in the FCC unit. 10% by weight of steam-treated Zn / zeolite pellets was mixed with steam-inactivated FCC catalyst Super Nova D (trade name) obtained from W. Grace. Super Nova D was deactivated at 770 ° C for 20 hours with 50% water vapor.

【0060】

Additives were tested for cracking activity and selectivity of gas oil using ASTM's microactivity test (or ASTM procedure D-3907). The properties of the reduced gas oil feed raw material are shown in the table below. The range of conversion was investigated by changing the ratio of catalyst to gas oil, and the reaction was carried out at 525 ° C. Products in the gasoline range from each mass balance were analyzed using sulfur GC (gas chromatography) (AED) to determine the S concentration of gasoline. Thiophene to C in synthetic crude oil (syncrude) to reduce experimental error in S concentration associated with fluctuations in gasoline distillation cutpoint₄-The amount of S species (excluding benzothiophene and S species with higher boiling point) ranging up to thiophene was measured and the total was defined as "S of fractional gasoline (cut-gasoline)".

【0061】

Properties of decompressed light oil feed Properties of charged raw materials API specific gravity 26.6 Aniline point (° C) 83CCR (% by weight) 0.23 Sulfur (% by weight) 1.05 Nitrogen (ppm) 600 Basic nitrogen (ppm) 310Ni (ppm) 0.32V (ppm) ) 0.68Fe (ppm) 9.15Cu (ppm) 0.05Na (ppm) 2.93 Distilled IBP (° C) 18050% by weight (° C) 38099.5% by weight (° C) 610 [0062]

Table 9 summarizes the performance of the catalyst. In the table, product selectivity is interpolated to a constant conversion rate, a conversion rate of 65% by weight or 70% by weight of the feed to the material at 220 ° C-.

【0063】

[Table 9]

Contact cracking performance of zinc / zeolite examples<img he="222" id="000010" wi="154" file="10_0003545652.tif" img-format="tif" img-content="drawing" /> 【0064】

The first three columns in Table 9 are Zn when 10% by weight of zeolite crystals are mixed with a common FCC catalyst to reduce gasoline sulfur.²⁺It summarizes the performance improvements with the ZSM-5 and MCM-41 zeolites replaced in. Gasoline sulfur concentration is reduced by 21.4% with Zn / ZSM-5 zeolite and 9.6% with Zn / MCM-41. Zn / ZSM-5 converts some of the substances in the gasoline and LCO range to C3 and C4 olefins and isobutane. These valuable C3 and C4 components are generally alkylated into petrol range products and then returned to the petrol pool for blending. Therefore, including the potential alkylate yield, the net gasoline volume does not decrease significantly.

【0065】

The S-based desulfurization efficiency of the feed was also compared to account for the volume loss of gasoline due to the various zeolites. When the desulfurization effect was recalculated to include the volume loss of gasoline, Zn / ZSM-5 resulted in a 34% reduction in S and Zn / MCM-41 resulted in a 9% reduction. We observed a slight increase in hydrogen and coke yields. The resulting poor performance of Zn / MCM-41 indicates that acid sites as well as metal sites are required to reduce sulfur in gasoline.

【0066】

Zn-exchanged MCM-49 and beta-zeolites also showed the potential to reduce gasoline sulfur under FCC conditions (Table 9). Gasoline S concentration was reduced by Zn / MCM-49 by 12% and by Zn / beta by 24%. When the results were recalculated to include gasoline volume loss, Zn / MCM-49 resulted in a 22% reduction in S and Zn / beta resulted in a 29% reduction. It was observed that the increase in hydrogen and coke yields was modest.

【0067】

Example 10: Evaluation of Flow Contact Cracking of Vanadium-Replaced Zeolite The vanadium-replaced zeolite of Example 2 is pelletized to a size such that the average particle size is about 70 T, and then 815 ° in a muffle furnace. Steam treatment was carried out in C for 4 hours. Steam treated V / ZSM-5, V / MCM-49 and V / Beta pellets 10% by weight, FCC catalyst Super Nova D (trade name) obtained from W. R. Grace (WR Grace) lost with steam It was mixed with the lived one. In addition, the V / USY pellet catalyst deactivated by steam was mixed with the equilibrium catalyst (E cat) from the FCC unit. Equilibrium catalysts have very low metal concentrations (120 ppm V and 60 ppm Ni). Table 10 summarizes the performance of V / zeolite.

【0068】

[Table 10]

Vanadium / zeolite catalytic cracking performance<img he="230" id="000011" wi="154" file="11_0003545652.tif" img-format="tif" img-content="drawing" /> 【0069】

Zeolites that were aqueous exchanged with vanadium were very effective in reducing gasoline S in the MAT evaluation. 10% by weight of V / ZSM-5, V / MCM-49, V / beta and V / USY (0.8%) mixed with the base cracking catalyst after deactivation with water vapor is 10% and 17 respectively. The favorable result was that a decrease in S of gasoline of%, 41% and 75% was observed (based on the S concentration of gasoline). V / ZSM-5, V / Beta and V / USY are all considered promising if the results are recalculated to include gasoline volume loss. It was observed that the increase in hydrogen and coke yields was modest.

【0070】

Example 11: Evaluation of fluid catalytic cracking of iron-replaced zeolite The iron-replaced zeolite of Example 3 is pelletized to a size such that the average particle size is about 70 T, and then 815 ° in a muffle furnace. Steam treatment was performed in C for 4 hours to imitate the equilibrium performance of the FCC unit. 10% by weight of Fe / MCM-49, Fe / Beta and Fe / USY pellets were mixed with an equilibrium catalyst from the FCC unit. Equilibrium catalysts have very low metal concentrations (120 ppm V and 60 ppm Ni). Table 11 summarizes the performance of Fe / zeolite.

【0071】

[Table 11]

Contact cracking performance of iron / zeolite examples<img he="230" id="000012" wi="154" file="12_0003545652.tif" img-format="tif" img-content="drawing" /> 【0072】

Zeolites replaced with iron are also effective in reducing gasoline S in the MAT evaluation. A mixture of 10 wt% Fe / MCM-49, Fe / Beta and Fe / USY in an equilibrium FCC catalyst resulted in a 30%, 39% and 50% reduction in gasoline S (gasoline S concentration standard), respectively. ). When the results were recalculated to include gasoline volume loss, Fe / MCM-49, Fe / Beta and Fe / USY reduced gasoline S by 44%, 46% and 51%, respectively. Fe / MCM-49 and Fe / Beta converted significant amounts of gasoline and LCO range products to C3 and C4 olefins and paraffin. Fe / USY maintained the yield of liquid and slightly reduced the yield of C3 and C4 olefins.

【0073】

The above yield structure is C from FCC in addition to low sulfur gasoline.₄^―If increased olefins and isoparaffins are desired, it suggests that metal-replaced ZSM-5, MCM-49 and beta are the preferred desulfurization additives. Metal-replaced USY catalysts can be preferred when it is more desirable to maximize gasoline yields.

【0074】

Example 12: Evaluation of fluid cracking of zeolite exchanged with cobalt The zeolite solid-phase exchanged with cobalt of Example 4 is pelletized, formed into a size having an average particle size of about 70 T, and then muffled. Steam cracking was performed in a furnace at 815 ° C for 4 hours to mimic the equilibrium performance of the FCC unit. 10% by weight of steam treated zeolite pellets was mixed with an equilibrium catalyst from the FCC unit. Equilibrium catalysts have very low metal concentrations (120 ppm V and 60 ppm Ni). Table 12 summarizes the performance of Co / zeolite.

【0075】

[Table 12]

Contact cracking performance of cobalt / zeolite examples<img he="230" id="000013" wi="154" file="13_0003545652.tif" img-format="tif" img-content="drawing" /> 【0076】

These results indicate that cobalt-exchanged zeolites are also effective in reducing gasoline S in the MAT assessment. Equilibrium FCC catalyst mixed with 10% by weight of Co / ZSM-5 (26/1), Co / ZSM-5 (450/1), Co / USY and Co / MCM-41 was 19% and 33%, respectively. , 39% and 18% reduced gasoline S (gasoline S concentration standard). When the results were recalculated to include gasoline volume loss, gasoline S decreased by 38%, 38%, 41% and 19%, respectively.

【0077】

Example 13: Evaluation of flow catalytic cracking of gallium-exchanged zeolite The gallium-exchanged beta and USY zeolites of Example 5 are pelleted and formed to a size such that the average particle size is about 70 T, and then Steam cracking at 815 ° C for 4 hours in a muffle furnace mimicked the equilibrium performance of the FCC unit. 10% by weight of zeolite pellets were mixed with an equilibrium catalyst from the FCC unit. Equilibrium catalysts have very low metal concentrations (120 ppm V and 60 ppm Ni). Table 13 summarizes the performance of Ga / zeolite.

【0078】

[Table 13]

Contact cracking performance of gallium / zeolite examples<img he="222" id="000014" wi="154" file="14_0003545652.tif" img-format="tif" img-content="drawing" /> 【0079】

As shown by these results, gallium-exchanged zeolites also reduce gasoline sulfur under FCC conditions. A 10 wt% mixture of Ga / beta and Ga / USY in an equilibrium FCC catalyst resulted in a 13% and 36% reduction in gasoline S (based on gasoline S concentration).

【0080】

Example 14: Evaluation of fluid catalytic cracking of ZSM-5 zeolite containing skeleton Fe The [Fe] ZSM-5 zeolite containing skeleton Fe of Example 6 is pelletized and sized so that the average particle size is about 70T. It was formed and then steamed in a muffle furnace at 815 ° C for 4 hours to mimic the equilibrium performance of the FCC unit. 10% by weight of zeolite pellets were mixed with an equilibrium catalyst from the FCC unit. Equilibrium catalysts have very low metal concentrations (120 ppm V and 60 ppm Ni). The performance of [Fe] ZSM-5 is summarized in Table 14.

【0081】

[Table 14]

Contact cracking performance of [Fe] ZSM-5 Examples<img he="222" id="000015" wi="154" file="15_0003545652.tif" img-format="tif" img-content="drawing" /> 【0082】

ZSM-5, which contains skeletal Fe, is effective in reducing gasoline S in these MAT assessments. Mixing [Fe] ZSM-5 with an equilibrium FCC catalyst showed a 54%, 39%, and 15% reduction in gasoline S, depending on the skeletal Fe content (gasoline S concentration basis). ZSM-5 with 4% Fe showed the most favorable desulfurization activity. H₂And the yield of coke increased slightly with desulfurization performance. The [Fe] ZSM-5 sample showed low gasoline volume loss and also showed a slight increase in coke and hydrogen yields.

【0083】

Example 15: Evaluation of fluid catalytic cracking of MeAPO molecular sheaves containing skeletal metal Pellets FeAPO-5 molecular sheaves containing skeletal iron of Example 7 and formed into a size such that the average particle size is about 70 T. Then, steam cracking was performed at 815 ° C for 4 hours in a muffle furnace to imitate the equilibrium performance of the FCC unit. 10% by weight of FeAPO-5 pellets were mixed with an equilibrium catalyst from the FCC unit. Equilibrium catalysts have very low metal concentrations (120 ppm V and 60 ppm Ni). Table 15 summarizes the performance of FeAPO-5.

【0084】

[Table 15]

FeAPO-5 Molecular Sheave Contact Decomposition Performance<img he="222" id="000016" wi="154" file="16_0003545652.tif" img-format="tif" img-content="drawing" /> 【0085】

FeAPO-5 molecular sheaves also reduce gasoline sulfur under FCC conditions. A mixture of 10% by weight of FeAPO-5 with an equilibrium FCC catalyst resulted in a 12% reduction in gasoline S (based on gasoline S concentration).

【0086】

The following examples, ie, Examples 16 and 17, show that it is important that the metal component is placed within the internal pore structure of the sheave component in order to effectively desulfurize the gasoline.

【0087】

Example 16: Performance Comparison of Vanadium-Replaced Beta and Vanadium / Alumina Catalysts Our invention of the concept of metal-replaced zeolite is in the form of fluid catalysts (catalysts A and B) that can be industrially implemented in this example. It was carried out and compared with the reference catalyst of Example 8 (V-impregnated alumina catalyst, not the invention).

【0088】

Catalyst A, a V / beta catalyst, is used as an NH with an industrial silica-alumina ratio of 35₄Manufactured using a mold beta. NH₄Type beta is N₂It was fired in 480 ° C for 3 hours and then in air at 540 ° C for 6 hours. The obtained H-type beta is VOSO₄V by exchange with solution⁴⁺I exchanged it at. The replaced beta was further washed, dried and air fired. The resulting V / Beta contains 1.3% by weight V. The flow catalyst was prepared by spray drying an aqueous slurry containing 40% by weight V / beta crystals in a silica-alumina gel / clay matrix. The matrix contained 25% by weight silica, 5% by weight alumina, and 30% by weight kaolin clay. The spray-dried catalyst was calcined at 540 ° C for 3 hours. Finally the catalyst contains 0.56% V. The catalyst was inactivated at 770 ° C. and 1 atm for 20 hours with 50% water vapor and 50% air prior to evaluation in the pilot unit.

【0089】

Catalyst B, a V / beta catalyst, was produced using the same procedure as catalyst A, except that vanadium was filled into the H-type beta catalyst by post-exchange of vanadium. Industrial NH with a ratio of silica to alumina of 35₄The mold beta was converted to a flow catalyst by spray drying an aqueous slurry containing 40% by weight beta crystals in a silica-alumina gel / clay matrix. The matrix contained 25% by weight silica, 5% by weight alumina, and 30% by weight kaolin clay. The spray-dried catalyst was calcined at 540 ° C for 3 hours. H-type beta catalyst is VOSO₄By exchanging with solution, V⁴⁺I exchanged it at. The replaced beta crystals were further washed, dried and calcined. The V / beta catalyst obtained contains 0.45% by weight V. The catalyst was inactivated at 770 ° C. and 1 atm for 20 hours with 50% water vapor and 50% air prior to evaluation in the pilot unit.

【0090】

Each catalyst was mixed in 10% by weight with an equilibrium catalyst from the FCC unit. Equilibrium catalysts have very low metal concentrations (120 ppm V and 60 ppm Ni). The performance is summarized in Table 16.

【0091】

[Table 16]

V / Beta vs. V / Al₂O₃Catalytic cracking performance<img he="230" id="000017" wi="154" file="17_0003545652.tif" img-format="tif" img-content="drawing" /> 【0092】

The catalysts (catalyst A and catalyst B) formulated on the basis of the present invention have been shown to reduce gasoline S species very effectively. When 10% by weight catalysts A and B (addition of 4% by weight beta zeolite) were mixed with the equilibrium FCC catalyst respectively, the sulfur concentration of gasoline was reduced by 30%. By comparison, the V / alumina catalyst reduced the S concentration in gasoline by only 15%. In the final mixing catalyst with the V / alumina catalyst, the desulfurization activity is considerably low, although the vanadium charge is quite large (0.1% vs. 0.02% V). These unexpected results clearly show the advantages of the present invention. In addition, the catalysts of the present invention have shown a smaller increase in hydrogen and coke yields.

【0093】

Example 17: Performance Comparison of Equilibrium FCC Catalysts Containing Vanadium-Replaced USY vs. Vanadium V / USY Catalysts Using USYs of Small Unit Cell Size (UCS 24.35 Å) with a Bulk Alumina Silica Ratio of 5.4 The catalyst C was produced. VOSO the H-type USY as it is obtained₄By exchanging with⁴⁺Replaced with. The replaced USY was further washed, dried and air fired. The resulting V / USY contains 1.3% by weight V. The flow catalyst was prepared by spray drying an aqueous slurry containing 40% by weight V / USY crystals in a silica-alumina gel / clay matrix. The matrix contained 25% by weight silica, 5% by weight alumina, and 30% by weight kaolin clay. The spray-dried catalyst was calcined at 540 ° C for 3 hours. Finally the catalyst contains 0.46% V. The catalyst was inactivated at 770 ° C. and 1 atm for 20 hours with 50% water vapor and 50% air prior to evaluation in the pilot unit.

【0094】

25% by weight V / USY was mixed with the equilibrium catalyst from the FCC unit. Equilibrium catalysts have very high metal concentrations (2900ppm V and 720ppm Ni). The performance is summarized in Table 17.

【0095】

[Table 17]

Contact cracking performance of V / USY-added catalyst vs. vanadium-rich E-catalyst<img he="230" id="000018" wi="154" file="18_0003545652.tif" img-format="tif" img-content="drawing" /> 【0096】

The catalyst (catalyst C) formulated based on our present invention has been shown to be additionally advantageous in reducing the S concentration of gasoline even for an equilibrium catalyst filled with a high concentration of V. When 25% by weight of Catalyst C (10% by weight of V / USY zeolite added) was mixed with the equilibrium FCC catalyst, the sulfur concentration of gasoline was additionally reduced by 28%. In both cases in Table 17, the final mixed catalyst vanadium fillings were similar (0.29% vs. 0.33% V), but catalyst C showed additional desulfurization activity.

【0097】

Example 18: Performance of Mo / MCM-49 / Alumina and Pd / Beta / Alumina Catalysts In this example, metal ions are incorporated into the pores of a zeolite to obtain a gasoline product with a low S concentration in the FCC. Indicates that proper metal selection is important.

【0098】

Catalyst D, a Mo / MCM-49 / alumina catalyst, was made using 65% by weight H-type MCM-49 / 35% by weight alumina extrusion. A physical mixture of 65 parts of MCM-49 and 35 parts of pseudo-boehmite alumina powder (La Roche Versal (trade name) alumina) is kneaded to form a homogeneous mixture for general auger extrusion. A machine was used to form a 1.5 mm cylindrical extrusion. Dry the extruded product with a belt filter at 120 ° C and N₂It was calcined at 540 ° C for 3 hours. Extruded product is 5cc NH₄NO₃After exchanging with ammonium using the solution, it was dried and air-baked at 540 ° C. The catalyst was then steam treated with 100% steam at 480 ° C for about 4 hours.

【0099】

Ammonium heptamolybdate and H₃PO₄The H-type MCM-49 / alumina extrusion was impregnated with 4% by weight Mo and 2% by weight P using a solution containing. Molybdenum ions in an ammonium heptamolybdate solution are polyanions consisting of 7 molybdenum atoms and 24 oxygen atoms [Mo.₇O₂₄]^6-In the cage structure (Greenwood and Earnshaw's Chemistry of the Elements, p. 1177, Pergamon Press, 1984). Mo polyanions are so large that they cannot enter the small pores of the zeolite, so all Mo atoms selectively attach to the outer surfaces of the zeolite crystals and the alumina matrix. The extrude impregnated with Mo was dried and calcined in air at 540 ° C for 3 hours.

【0100】

The catalyst E, which is a Pd / beta / alumina catalyst, was produced by the following procedure. A physically mixed mixture of 65 parts of zeolite beta and 35 parts of pseudoboehmite alumina powder was kneaded to form a uniform mixture. A diluted solution of tetraamine palladium chloride (corresponding to 0.6 wt% Pd) was added to adjust the solid concentration of the muller mix to make an extrudable paste. Using a common wood auger extruder, the Muller mixture was formed into a 1.5 mm cylindrical extruder. The extruded product was dried overnight at 120 ° C., then nitrogen calcined at 480 ° C. for 3 hours and then air calcined at 540 ° C. for 6 hours.

【0101】

The catalysts D and E were formed to a size such that the average particle size was about 70 m, and then steam-treated at 540 ° C for 4 hours in a muffle furnace to mimic the equilibrium performance of the FCC unit. 10% by weight of the additive was mixed with a laboratory-inactivated FCC catalyst (Super Nova D (trade name), WR Grace). The performance is summarized in Table 18.

【0102】

[Table 18]

Catalytic cracking performance of Mo / MCM-49 and Pd / beta catalysts<img he="197" id="000019" wi="154" file="19_0003545652.tif" img-format="tif" img-content="drawing" /> 【0103】

The Mo / MCM-49 / Alumina catalyst (not invented) was found to reduce gasoline sulfur by only 2.5%, resulting in a very poor ability to desulfurize gasoline. The poor performance of this catalyst is probably due to the selection of the undesired metal (Mo) and the location of the Mo (all within the binder as opposed to inside the small pore structure of the zeolite).

【0104】

The Pd / beta catalyst showed extremely poor performance, increasing the S concentration of gasoline by 80%. This inferior performance of Pd / Beta is probably due to the selection of unwanted metals with high hydrogenation capabilities. Both catalysts showed a significant increase in coke and hydrogen yields. This example shows that the location and selection of the metal plays an important role in desulfurization of gasoline under FCC conditions.

【0105】

The alpha test mentioned above is a conventional method of measuring the overall acidity of a solid material, such as a molecular sieve, including both internal and external acidity. The study was conducted in US Pat. No. 3,354,078; the Journal of Catalysis, Vol. 4, p. 527 (1965)); Vol. 6, p. 278 (1966); Vol. 61. , 395 (1980). The alpha values reported herein are measured at a constant temperature of 538 ° C.

【0106】

The abbreviations used herein are: "FCCU" for "fluid catalytic decomposition unit"; "MeAPO" for "metalloaluminophosphate"; "MeAPSO" for "metal" "Metal aluminophosphosilicate"; "REY" is "Y (Rare Earth exchanged Y)"; "ELAPO" is "Element aluminophosphate;" Or element aluminophosphate; "ELAPSO" means "element aluminophosphosilicate"; "AlPO" means "aluminophosphate"; "UCS" means "unit" -Unit Cell Size; "MAT" means "Micro Activity" Test; or Microactivity Test) (ASTM D-3907) ";" IC₄"Yield" is "C₄-Isomer yields ";" LFO "is" Light Fuel Oil ";" HFO "is" Heavy Fuel Oil "; and" LCO "is" Light Cycle Oil " ".

【0107】

In the present specification, "bulk SiO"₂/ Al₂O₃The term "(or silica: alumina) ratio" is used intended to refer to the overall silica / alumina ratio in zeolite as determined by conventional chemical analysis.