Polynary vanadyl pyrophosphate

The present invention relates to a multidimensional vanadyl pyrophosphate, a method for producing the multidimensional vanadyl pyrophosphate, and a heterogeneous contact gas phase oxidation, advantageously a heterogeneous contact gas phase of a hydrocarbon having at least 4 carbon atoms. With respect to the use of the multidimensional vanadyl pyrophosphate for oxidation.

Vanadyl pyrophosphate (VO)₂P₂O₇Non-homogeneous catalysts based on (so-called VPO catalysts) are used during the industrial oxidation of n-butane to maleic anhydride and during the oxidation reaction of a series of other hydrocarbons.

Vanadyl pyrophosphate catalysts are typically prepared as follows: (1) Vanadyl hydrogen phosphate hemihydrate precursor (VOHPO)₄ 1 / 2H₂O) is a pentavalent vanadium compound (eg V)₂O₅), Phosphorus or trivalent phosphorus compounds (eg, ortho-and / or pyrophosphate, phosphate ester or phosphorous acid) and reducing alcohols (eg, isobutanol) to form a precipitate. Isolated, dried, and optionally molded (eg, tableted), and (2) the precursor was preformed by roasting with vanazyl pyrophosphate ((VO)).₂P₂O₇). See, for example, EP-A0520972 and WO 00/72963.

By using alcohol as a reducing agent, generally several mass% of an organic compound remains in the precursor in an enclosed state, and this organic compound cannot be removed even by careful washing. This organic compound adversely affects the catalytic properties of the catalyst during further catalyst production, especially during calcination. For example, during subsequent calcination, evaporation or thermal decomposition of the encapsulated organic compound occurs under the formation of gaseous components, which can lead to increased pressure inside the crystal and thus decomposition of the catalytic structure. This unfavorable effect is particularly pronounced during roasting under oxidizing conditions, because of the formation of oxidized decomposition products, such as carbon monoxide or carbon dioxide, which results in an essentially larger amount of gas. Is formed. Furthermore, the oxidation of this organic compound locally produces a very large amount of heat, which can lead to thermal damage to the catalyst.

In addition, the encapsulated organic compound has a significant effect on the local oxidation number of vanadium. For example, Kubias et al., In Chemie Ingenieur Technik 72 (3), 2000, pp. 249-251, anaerobic (under non-oxidizing conditions) the vanadyl hydrogen phosphate hemihydrate precursor obtained from an isobutanol solution. It proves the reducing effect of organic carbon during calcination. Anaerobic calcination gives an average oxidation number of 3.1 vanadium in the above examples, whereas aerobic calcination (under oxidative conditions) gives an average oxidation number of about 4 vanadium. ..

Proposals have also been made to add small amounts of divalent, trivalent or tetravalent transition metal oxides, so-called cocatalysts, to vanadyl pyrophosphate to improve catalytic behavior (GJ Hutchings, J. Mater. Chem. 2004, 14, 3385-3395; KV Narayana et al, Z. Anorg. Allg. Chem. 2005, 631, 25-30). Here, the mode of action of the co-catalyst has not been fully clarified at present.

No information has been taught in publications regarding the presence and catalytic behavior of single-phase multidimensional vanadium (IV) phosphates containing divalent, trivalent or tetravalent transition metals different from vanadium. Absent.

Mixed valence vanadium (III, IV) diphosphate, V^III₂(V^IVO) (P₂O₇)₂Has long been known and crystallographically characterized (see JW Johnson et al., Inorg. Chem. 1988, 27, 1646-1648). From BG Golovkin, VL Volkov, Russ. J. Inorg. Chem. 1987, 32, 739-741, diphosphate V as well.₃O₄(P₂O₇) Is known, but the description regarding its characterization is completely missing.

An object of the present invention is to provide a novel multi-dimensional vanadyl pyrophosphate.

Another object of the present invention has been to provide a novel multidimensional vanadyl pyrophosphate having catalytic properties for heterogeneous contact vapor phase oxidation.

Another object of the present invention is to provide a novel multidimensional vanadyl pyrophosphate that can change the catalytic properties of a known heterogeneous catalyst based on vanadyl pyrophosphate.

Another object of the present invention is to provide a novel method for producing vanadyl pyrophosphate and a heterogeneous contact gas phase oxidation method.

Accordingly, it has a crystal structure, general formula I (VO)_a(M_1-bV_{b b})₂(P₂O₇)_c[During the ceremony, M represents one or more metals selected from Ti, Zr, Hf, Cr, Fe, Co, Ni, Ru, Rh, Pd, Cu, Zn, B, Al, Ga and In. a indicates a value from 0.5 to 1.5, b indicates a value from 0 to 0.9, c indicates a value between 1.5 and 2.5] In the multidimensional vanadyl pyrophosphate, the powder X-ray diffraction pattern of the crystal structure has the following 10 lattice spacings d [Å] =<chemistry num="1"><img file="JP2010524809A_D0001.tif" /></chemistry>At least 7 of the diffractive reflections in, advantageously characterized by the presence of all, a novel multi-dimensional vanadyl pyrophosphate was found.

In the present application, X-ray diffraction reflection is expressed in the form of lattice spacing d [Å] regardless of the wavelength of the X-ray used. The wavelength λ of the X-ray used for diffraction and the diffraction angle θ (in the present specification, the peak position of the reflection in the 2θ plot is used as the position of the diffraction reflection) are correlated by the following Bragg's equation. :: 2sinθ = λ / d Here, d is the lattice spacing of the three-dimensional atomic arrangement belonging to each diffraction reflection.

The powder X-ray diffraction pattern of the multidimensional vanadyl pyrophosphate of formula I according to the present invention is characterized by the above diffraction reflection. Diffractive reflections are generally the approximate relative intensities (I) shown in Table 1._rel[%]) Is shown. Other diffractive reflections of powder X-ray diffraction patterns, which are usually less intense than this, are not considered in Table 1.

Table 1<tables num="1"><img file="JP2010524809A_D0002.tif" /></tables>

However, depending on the crystallinity of the multidimensional vanadyl pyrophosphate according to the present invention and the texture of the obtained crystal, amplification or attenuation of the intensity of diffraction reflection in the powder X-ray diffraction pattern can occur. Attenuation can occur until the individual diffraction reflections in the powder X-ray diffraction pattern are no longer detectable.

It will be apparent to those skilled in the art that the mixture of vanadyl pyrophosphate and other crystalline compounds according to the present invention has additional diffractive reflections. Such a mixture of vanadyl pyrophosphate and other crystalline compounds can be intentionally produced by mixing vanadyl pyrophosphate according to the present invention, or vanadyl polyphosphate according to the present invention. Can result from an incomplete reaction of the starting material or the formation of heterogeneous phases with different crystal structures during the production of.

Advantageously, in formula I, a has a value of 0.8 to 1.2, especially about 1.

Advantageously, in Equation I, b has a value between 0 and 0.4. In certain embodiments of the present invention, b has a value of 0.

Advantageously, in formula I, c has a value of 1.8-2.2, especially about 2.

In formula I, M is one metal selected from Ti, Zr, Hf, Cr, Fe, Co, Ni, Ru, Rh, Pd, Cu, Zn, B, Al, Ga and In, or 2 of the metal. Represents the above combination. Advantageously M represents a metal selected from Cr and Fe.

The advantageous vanadyl pyrophosphate compound according to the present invention has the following formula: (VO) Fe₂(P₂O₇)₂Have.

The multidimensional vanadyl pyrophosphate according to the present invention can be obtained in various forms.

The multidimensional vanadyl pyrophosphate according to the present invention, on the one hand, can be obtained by a solid reaction in a closed system. For this purpose, vanadium oxygen compounds, vanadium phosphorus compounds, vanadium mixed oxygen phosphorus compounds, element vanadium, metal M oxygen compounds, metal M phosphorus compounds, and metal M mixed oxygen phosphorus compounds, and elements. React at least two reactants selected from metal M.

In this case, the reactants are generally (i) the reactants provide the desired stoichiometry of the elements in formula I, and (ii) the valences of the elements other than oxygen in the reactants are multiplied by a factor. The sum of the products is selected to correspond to the sum of the products of the valences of the elements other than oxygen in Equation I multiplied by a coefficient. The starting compound may be selected such that all elements in the starting compound other than oxygen already have the same valence as the element has in Formula I. Instead, the starting compound is selected such that some or all of the non-oxygen elements in the starting compound have different valences than those elements have in Formula I. May be. By a redox reaction, eg, synproportionation, during a solid reaction, an element other than oxygen obtains the valence that the element has in Formula I. For example, an equivalent combination of vanadium (III) compound and vanadium (V) compound can be used, from which tetravalent vanadium is formed during the solid reaction.

The required starting compounds in the form of oxides, phosphates, oxidized phosphates, phosphides, etc. are either commercially available or known in the literature, or are readily available to those skilled in the art similar to known production modalities. Can be synthesized.

The starting material is completely mixed, for example by milling. The solid reaction is typically carried out at a temperature of at least 500 ° C, for example 650 ° C to 1100 ° C, especially about 800 ° C. Typical reaction times are, for example, 24 hours to 10 days. Suitable reaction vessels consist of, for example, quartz glass or corundum.

Suitable mineralizing agents, such as iodine or PtCl, are advantageous during solid reactions to obtain products or single crystals with high crystallinity.₂Can be used together.

Unlike that a) Produce a dry mixture of vanadium source, metal M source and phosphate source, b) Here, in some cases, by preparing a reduction equivalent, the vanadium and / or the metal M is transformed into the valence state of the vanadium and the metal M in Formula I, and c) Calcinate the dry mixture at at least 500 ° C Thereby, the multidimensional vanadyl pyrophosphate according to the present invention can be produced.

To this end, from a suitable source of the elemental components of the multidimensional vanadyl pyrophosphate according to the present invention, a dry mixture of fine grains, as complete as possible in the desired component stoichiometric amount, is produced.

Complete mixing of the starting compounds can be done dry or wet.

When done dry, the starting compound is advantageously used as a fine powder and is calcinated (heat treated) after mixing and optionally consolidation.

However, advantageously, complete mixing is done wet, i.e. in dissolved or suspended form. In this case, the starting compounds are usually mixed with each other in the form of an aqueous solution (possibly in combination with a complexing agent) and / or a suspension. Subsequently, the aqueous solution or suspension is dried and then calcinated after drying.

Drying can be done by vacuum evaporation, freeze-drying, or conventional evaporation. However, advantageously the drying process is carried out by spray drying. The outlet temperature is usually 70-150 ° C; spray drying can be done in parallel or countercurrent.

Suitable vanadium sources are, for example, vanadyl sulphate hydrate, vanadyl acetylacetoneate, vanadate, such as ammonium metavanadate, vanadium oxide, for example divanadium pentoxide (V).₂O₅), Vanadium dioxide (VO₂) Or divanadium trioxide (V)₂O₃), Vanadium halides, such as vanadium tetrachloride (VCl)₄) And vanadyl halides, such as VOCl₃Is. Vanadium pentoxide and ammonium vanadate are advantageous sources of vanadium.

As a source for the metal M, compounds of all elements capable of forming oxides and / or hydroxides upon heating (possibly in the presence of molecular oxygen, eg air) are relevant. Of course, as such starting compounds, the elemental oxides and / or hydroxides may already be used in combination, or they may be used exclusively. Advantageously, the source of the metal M is selected from the nitrates, carboxylates, carbonates, bicarbonates, basic carbonates, oxides, hydroxides and oxide hydroxides of the metal M.

Suitable phosphate sources are compounds containing phosphate bases or form phosphate bases by a redox reaction and / or upon heating (possibly in the presence of molecular oxygen, eg air). It is a possible compound. This includes phosphoric acid, especially orthophosphoric acid, pyro- or metaphosphoric acid, phosphite, hypophosphoric acid, phosphate or hydrogen phosphate, such as diammonium hydrogen phosphate and elemental phosphorus, such as white phosphorus. Is. Advantageously, the phosphate source is formed, at least in part, from phosphorous acid or hypophosphorous acid, optionally in combination with orthophosphoric acid.

As a source of vanadium or metal M, vanadium or metal M is more than the valence in formula I (ie, O present in formula I).^2-And PO₄^3-If compounds with higher valences (than the formal valences of V and M required to achieve electrical neutrality with anions) are used, vanadium and by preparing reduction equivalents advantageously / Or the metal M must be changed to the valence state of vanadium and metal M in formula I.

The reduction equivalent is made from a reducing agent capable of reducing the polyvalent form of vanadium or metal M. The reduction is carried out during the preparation of the dry mixture or at the latest during calcination. Advantageously, the preparation of the completely dry mixture is an inert gas atmosphere (eg N) to ensure improved control over the oxidation number.₂) It is done below.

Advantageous reducing agents for this purpose are hypophosphorous acid, phosphite, hydrazine (as a free base or hydrate, or salts thereof, for example in the form of hydrazine dihydrochloride, hydrazine sulfate), hydroxylamine. From free bases or salts thereof, such as in the form of hydroxylamine hydrochloride, nitrosylamine, element vanadium, element phosphorus, borane (in the form of complex boron hydrides, eg sodium borohydride) or oxalic acid. Be selected. Phosphorous acid and / or hypophosphorous acid are advantageous reducing agents.

Of course, certain reducing agents, such as hypophosphorous acid or phosphorous acid, can be used simultaneously as phosphate sources, or elemental vanadium can be used simultaneously as vanadium sources.

The dry mixture is heat treated at a temperature of at least 500 ° C, preferably 700-1000 ° C, especially about 800 ° C. The heat treatment can be performed in an oxidizing atmosphere, a reducing atmosphere, and further in an inert atmosphere. The oxidizing atmosphere corresponds to, for example, air, molecular oxygen-enriched air, or oxygen-enriched air. However, advantageously the heat treatment is carried out under an inert atmosphere, eg, under molecular nitrogen and / or a rare gas. Heat treatment is usually performed at normal pressure (1 atm). Of course, the heat treatment can also be performed under vacuum or overpressure.

When the heat treatment is performed in a gaseous atmosphere, the atmosphere may be stationary or fluid. Advantageously, the atmosphere is fluid. Overall, the heat treatment can take up to 24 hours or more.

The present invention further relates to at least one vapor phase oxidation catalyst containing vanadyl pyrophosphate according to the present invention. The multi-element vanadyl pyrophosphate can be used as it is, for example, as a powder or as a heterogeneous catalyst in the form of a molded product.

Advantageously, the molding is done by tableting. For tableting, the powder is generally added with a tableting aid and completely mixed.

Tableting aids are usually catalytically inert and improve the tableting properties of the powder, for example by improving slipperiness and fluidity. Suitable and advantageous tableting aids include graphite or boron nitride. The added tableting aid usually remains in the activated catalyst.

The powder is tableted and subsequently crushed into crushed pieces.

Molding into a molded product may be carried out, for example, by applying to a carrier a mixture containing at least one vanadyl pyrophosphate according to the present invention or at least one vanadyl pyrophosphate according to the present invention. it can.

The carrier is advantageously chemically inert. That is, the carrier essentially does not interfere with the progress of catalytic vapor phase oxidation catalyzed by the multidimensional vanadyl pyrophosphate according to the present invention.

Materials for carriers include, in particular, aluminum oxide, silicon dioxide, silicates such as clay, kaolin, steatite, pumice, aluminum silicate and magnesium silicate, silicon carbide, zirconium dioxide and thorium dioxide.

The surface of the carrier may be smooth or rough. It is advantageous for the surface of the carrier to be rough, as the increased surface roughness usually results in increased adhesion of the applied active material shell.

Further, the carrier material may be porous or non-porous. Advantageously the carrier material is non-porous, i.e., the total volume of pores is advantageously less than 1% by volume with respect to the volume of the carrier.

The thickness of the catalytically active layer is usually 10 to 1000 μm, for example 50 to 700 μm, 100 to 600 μm or 150 to 400 μm.

In principle, a carrier having a structure of an arbitrary shape can be mentioned. Its longitudinal extension is usually 1-10 mm. However, advantageously, a sphere or cylinder, especially a hollow cylinder, is used as the carrier.

The production of the shell-type catalyst is extremely simple, in which the multidimensional vanadyl pyrophosphate material of the general formula (I) is preformed, converted into a fine form, and subsequently applied to the surface of the carrier using a liquid binder. Performed in style. To this end, the surface of the carrier is moistened with a liquid binder in a very simple manner, and contact with the fine-grained material causes a layer of active material to adhere to the moistened surface. Finally, the coated carrier is dried. Not surprisingly, this process is repeated to achieve greater layer thickness.

The multidimensional vanadyl pyrophosphate according to the present invention can also be used to change the catalytic properties, in particular the conversion and / or selectivity of known vanadyl pyrophosphate-based catalysts. For this purpose, the multidimensional vanadyl pyrophosphate according to the present invention can be used, for example, as a co-catalyst phase in a vanadyl pyrophosphate-based catalyst. In that case, the catalyst advantageously comprises the first phase and the second phase in the form of a three-dimensionally extending range, and the range and the local surroundings of the range are separated by different chemical compositions. In this case, the first phase contains a catalytically active material based on vanadyl pyrophosphate, and the second phase contains at least one vanadyl pyrophosphate according to the present invention. In this case, (i) the fine particles of the second phase are dispersed in the first phase, or (ii) the first phase and the second phase are mutually fine-grained first. It is distributed like a mixture of a phase and a finely granular second phase.

The production of the two-phase catalyst described above includes, for example, vanadyl hydrogen phosphate hemihydrate precursor (VOHPO).₄ 1 / 2H₂O) can be produced and this can be done by mixing with the preformed particles of the second phase from the multidimensional vanadyl pyrophosphate according to the invention, molding the resulting material and calcinating. it can. The vanadyl phosphate hemihydrate precursor is a compound of pentavalent vanadium (eg V) by a method known per se.₂O₅), A compound having pentavalent or trivalent phosphorus (eg, ortho-and / or pyrophosphate, phosphate ester or phosphorous acid) and a reducing alcohol (eg, isobutanol) to synthesize a precipitate. It can be obtained by isolation. See, for example, EP-A0520972 and WO 00/72963.

The catalyst according to the invention, wherein the catalytically active material contains at least one of the multiple vanadyl pyrophosphates defined above, and a vanadyl pyrophosphate-based catalyst can also be combined in the form of structured packing. For example, a gas stream containing a hydrocarbon and molecular oxygen to be oxidized is subjected to a first gas phase oxidation catalyst layer located upstream in the flow direction of the gas stream, and then a second or other gas phase located downstream. One or more layers of the oxidation catalyst can be conducted, in which case the first layer or the second layer or one of the other layers comprises the catalyst according to the invention.

The present invention further relates to a partial vapor phase oxidation method or an ammoxidation method in which a gas stream containing hydrocarbons and molecular oxygen is brought into contact with the catalyst according to the present invention. In the case of ammoxidation, the gas stream additionally contains ammonia. Ammoxidation is a heterogeneous contact process that, within the scope of the present invention, reacts methyl-substituted alkenes, allenes and hetarene with ammonia and oxygen in the presence of a transition metal catalyst to convert them to nitriles. Is interpreted as.

The partial vapor phase oxidation method is utilized in an advantageous embodiment of the production of maleic anhydride, wherein the hydrocarbon used comprises at least 4 carbon atoms.

The partial vapor phase oxidation method or ammoxidation method according to the present invention is generally used in a tube bundle type reactor. It can also be used in fluidized bed reactors.

Hydrocarbons generally include aliphatic and aromatic, saturated and unsaturated hydrocarbons having at least 4 carbon atoms, such as 1,3-butadiene, 1-butene, cis-2-butene, trans-2-butene. , N-butene, C₄-Mixed, 1,3-pentadiene, 1,4-pentadiene, 1-pentene, cis-2-pentene, trans-2-pentene, n-pentane, cyclopentadiene, dicyclopentadiene, cyclopentene, cyclopentane, C₅-Mixtures, hexene, hexane, cyclohexane and benzene are suitable. 1,3-butadiene, 1-butene, cis-2-butene, trans-2-butene, n-butane, benzene or mixtures thereof are advantageously used.

The use of n-butane and n-butane-containing gases and liquids is particularly advantageous. The n-butane used may be, for example, from a rare gas, from a steam cracker, or from an FCC cracker.

The addition of hydrocarbons is generally carried out under metering, i.e., under a certain standard of a predetermined amount per hour. Hydrocarbons can be supplied in liquid or gaseous form. Liquid supply and subsequent evaporation in front of the reactor inlet are advantageous.

As the oxidant, oxygen-containing gases such as air, synthetic air, oxygen enriched gases or so-called "pure oxygen" (ie, eg, oxygen derived from aerobic decomposition) are used. Oxygen-containing gas is also advantageously added under metering.

The gas conducting the reactor generally has a hydrocarbon concentration of 0.5 to 15% by volume and an oxygen concentration of 8 to 25% by volume. The balance up to 100% by volume is other gases such as nitrogen, rare gas, carbon monoxide, carbon dioxide, water vapor, oxygen-containing hydrocarbons (eg methanol, formaldehyde, formic acid, ethanol, acetylaldehyde, acetic acid, propanol). , Propionaldehyde, propionic acid, acrolein, crotonaldehyde) and mixtures thereof. In the case of selective oxidation of n-butane, the n-butane content with respect to the total amount of hydrocarbons is preferably more than 90%, especially more than 95%.

In order to achieve a long catalyst life and further improvement in conversion, selectivity, yield, catalyst loadability and space-time yield, the method according to the invention favorably supplies the gas with a volatile phosphorus compound. To.

Its concentration is at least 0.2 parts per million at the reactor inlet, i.e. the volume integral of the volatile phosphorus compound relative to the total volume of gas at the reactor inlet 0.2-10.^-6Is. A content of 0.2 to 20 parts per million, particularly preferably 0.5 to 10 parts per million, is advantageous.

Volatile phosphorus compounds are interpreted as all phosphorus-containing compounds that are present in the form of gaseous at the desired concentration under conditions of use. Suitable volatile phosphorus compounds include, for example, phosphine and phosphate esters. C₁-C₄-Alkyl-phosphate esters are particularly advantageous, with trimethyl phosphate, triethyl phosphate and tripropyl phosphate, especially triethyl phosphate.

The method according to the invention is generally carried out at a temperature of 300-500 ° C. The above temperature is interpreted as the temperature of the catalyst layer present in the reactor, which is present in the absence of a chemical reaction during the implementation of the method.

If the temperatures are not exactly equal at all points, the concept means a number mean of temperatures along the reaction region. In particular, this means that the actual temperature on the catalyst can be outside the above range based on the heat generated by the oxidation reaction. Advantageously, the method according to the invention is carried out at a temperature of 380 to 460 ° C, particularly preferably 380 to 430 ° C.

The method according to the invention can be carried out at a pressure below normal pressure (eg, up to 0.05 MPa abs) and above normal pressure (eg, up to 10 MPa abs). The pressure may be interpreted as the pressure in the reactor unit. Pressures of 0.1 to 1.0 MPa abs, especially preferably 0.1 to 0.5 MPa abs, are advantageous.

The method according to the invention can be carried out in two advantageous variants, one with a "straight path" and one with a "return". In the case of a "linear path", maleic anhydride and optionally oxygenated hydrocarbon by-products are removed from the reactor emissions and the residual gas mixture is exhausted and optionally heat is utilized. In the case of "return", the residual gas mixture, which also removes maleic anhydride and optionally oxygenated hydrocarbon by-products from the reaction emissions and contains unreacted hydrocarbons, is completely or partially removed. Return to the reactor. Another variant of "return" is the removal of unreacted hydrocarbons and their return to the reactor.

In a particularly advantageous embodiment for producing maleic anhydride, n-butane is used as the starting hydrocarbon and heterogeneous catalytic vapor phase oxidation is carried out on the catalyst according to the invention in a "linear pathway". ..

The present invention will be described in detail with reference to the accompanying figures and the following examples.

Figure 1 shows (VO) Fe₂(P₂O₇)₂The powder X-ray diffraction pattern of is shown.

Figure 2 shows (VO) Fe produced by other methods.₂(P₂O₇)₂The powder X-ray diffraction pattern of is shown.

X-ray diffraction test is CuK as X-ray_α1Based on X-ray diffraction pattern obtained using wire (λ = 1.54051Å) (Siemens diffractometer Theta-Theta D-5000: tube voltage: 40kV, tube current: 40mA, aperture V20 (variable), collimator V20 (variable), secondary monochromator aperture (0.1 mm), detector aperture (0.6 mm), measurement interval (2θ): 0.02 [°], measurement time per step: 2.4s, detector: scintillation counter) ..

<figref num="1">(VO) Fe₂(P₂O₇)₂The figure which shows the powder X-ray diffraction pattern of.</figref><figref num="2">(VO) Fe manufactured by other methods₂(P₂O₇)₂The figure which shows the powder X-ray diffraction pattern of.</figref>

Example 1: (VO) Fe₂(P₂O₇)₂Manufacturing of The title compound was obtained by the following empirical formula:<chemistry num="2"><img file="JP2010524809A_D0003.tif" /></chemistry>

In a glass reactor, 6.0 L of water, Fe (NO)₃)₃ 9H₂O (Sigma Aldrich, Seelze, Germany) 808.0g, NH₄VO₃(77.57% V₂O₅HC Starck GmbH, Goslar, Germany with content (= V 0.5 mol) 117.0 g, H₃PO₄(85% (= P 3.5 mol), Sigma Aldrich, Seelze, Germany) 403.5 g and H₃PO₃A mixture of 82.0 g (50% (= P 0.5 mol), Sigma Aldrich, Seelze, Germany) was heated to 90 ° C with stirring and stirred at this temperature for 2 hours. Spray dryer the resulting suspension (Soborg, Denmark, Mobile Minor manufactured by Niro A / S)^TM 2000, MM, inlet temperature: 330 ° C, outlet temperature: 107 ° C) and dried under nitrogen. The obtained spray powder was baked at 800 ° C. for 2 hours in a quartz rotating tube having an internal volume of 1 L in a nitrogen atmosphere.

The obtained powder is 3.5m²It had a BET specific surface area of / g. From the powder X-ray diffraction pattern (Fig. 1), the following 2θ values and the associated intensities I and lattice spacing d were found.

<tables num="2"><img file="JP2010524809A_D0004.tif" /></tables>

Example 2: (VO) Fe₂(P₂O₇)₂Other manufacturing The title compound was obtained by the following empirical formula:<chemistry num="3"><img file="JP2010524809A_D0005.tif" /></chemistry>

Water 6.0L, V in glass reactor₂O₅[Calculated as&gt; 99%, 0.5 mol, V] (GfE Umwelttechnik GmbH, Nuremberg, Germany) 90.9 g, FeOOH [Calculated as 95%, 2.0 mol, Fe] (Sicopur Gelb, BASF Akpyridine, Ludwigshafen, Germany) 187.1 g, H₃PO₄(85% (= P 3.5 mol), Sigma Aldrich, Seelze, Germany) 403.5 g and H₃PO₃A mixture of 82.0 g (50% (= P 0.5 mol), Sigma Aldrich, Seelze, Germany) was heated to 90 ° C with stirring and stirred at this temperature for 2 hours. Spray dryer the resulting suspension (Soborg, Denmark, Mobile Minor manufactured by Niro A / S)^TM 2000, MM, inlet temperature: 330 ° C, outlet temperature: 107 ° C) and dried under nitrogen. The resulting spray powder was calcinated in two steps: First, the powder was calcinated in a nitrogen atmosphere in a quartz rotating tube with an internal volume of 1 L at 600 ° C. for 2 hours. The product was ground in a ball mill for 15 minutes and baked in a nitrogen atmosphere at 850 ° C for an additional 2 hours.

The obtained powder is 1.6m²It had a BET specific surface area of / g. From the powder X-ray diffraction pattern (Fig. 2), the following 2θ values and the associated intensities I and lattice spacing d were found.

<tables num="3"><img file="JP2010524809A_D0006.tif" /></tables>