MXPA98000508A - Preparation of catalysts based on antimonatode vanadio, using sno2-x - Google Patents

Abstract

A method for preparing a catalyst having elements and the proportions indicated by the following empirical formula: VSbmAaDdOx, where A is one or more of Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca, Sr, Ba, Co, Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, Ace, B, Al and Mn where m is from 0.5 to 10, a is greater than zero to 10, d is zero to 10, x is determined by the oxidation state of the cations present, which comprises making an aqueous slurry of a mixture of the source batch materials, comprising the compounds of the elements to be included in the final catalyst, followed by drying and heat calcination of the mixture to obtain an active catalyst, wherein the source batch material for the tin is a solution comprising SnO2uxH2O, where x is > = 0 dispersed in tetraalkyl ammonium hydroxide, wherein the tetraalkyl ammonium hydroxide is defined by the following formula: (C n H 2n + 1) 4 NOH, wherein 5 > = n > = 1, dry the slurry and calcined the mixture at a calcination temperature greater than at least 500

Description

PREPARATION OF CATALYSTS BASED ON VANADIO ANTIMONATE, USING SnO? .xH? Q BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a method for the preparation of tin-containing vanadium-antimony oxide catalysts, useful for the catalytic ammoxidation of paraffins or olefins of 3 to 5 carbon atoms, in the form more specific for the preparation of catalysts for the ammoxidation of propane or isobutane or propylene or isobutylene to obtain their corresponding mononitrile, acrylonitrile or methacrylonitrile a, β-unsaturated. In addition, the catalysts can be used in the ammoxidation of methylpyridine, m-xylene or in the oxidation of o-xylene to give cyanopyridine, isophthalonitrile or phthalic anhydride, respectively. More specifically, the invention relates to the use of Sn02 * xH20, wherein x > 0, dispersed in a solution of a tetraalkyl ammonium hydroxide as the reagent for tin in the preparation of the catalysts containing vanadium and antimony and tin in oxide form. These types of catalysts are described, for example, in U.S. Patent Nos. 3,681,421, 4,788,317, 5,008,427, and in the British specifications.

E'1049 / 98MX Nos. 1,336,135 and 1,336,136, published in November 1973. Not all tin sources are equally effective as promoters in the vanadium-antimony oxide catalysts for the oxidation and ammoxidation of 3 and 4 carbon atoms alkane, particularly the ammoxidation. In fact, U.S. Patent No. 5,214,016 and EPO 691306-A1 teach that the source of the tin promoter is critical to the performance characteristics of the finished catalyst. It is believed that the tin should be present in a very finely divided form in the precursors of these catalysts so that the tin is fully reactive when the reaction takes place in the solid state, in the calcination of the mixture of the catalyst precursors. The colloidal solution of tin oxide is a suitable source in the manufacture of catalysts of the present invention; refer to U.S. Patent No. 5,088,427. However, ground tin oxide or tin oxide made by reacting tin metal with nitric oxide are decidedly less effective sources in the preparation of catalysts. While the current colloidal solution of tin oxide, commercially available, is effective, it has a serious disadvantage because it is a very expensive source.

E'1049 / < 8MX SUMMARY OF THE PRESENT INVENTION It is an object of the present invention to provide a method for making a superior oxidation catalyst (particularly ammoxidation), while avoiding the use of commercially available standard colloidal tin oxide solutions. It is another object of the invention to make a catalyst at a fraction of the cost with respect to the tin component as compared to the use of the commercially available tin oxide current colloidal solution, as the tin source in the catalyst precursor. Other objects, as well as aspects, characteristics and advantages of the invention will become apparent apparent from a study of the specification including the specific examples. The foregoing objects and others are achieved with the present invention according to which a method is provided for making a catalyst containing vanadium, antimony and tin in the oxide state, which comprises making an aqueous slurry of a mixture of the materials of the source batch, which comprise the compounds of the elements to be included in the final catalyst, followed by the drying and calcination of the mixture to form an active catalyst, wherein the material of the The source batch for tin is a solution comprising Sn02 * xH20, where x > 0 dispersed in tetraalkyl ammonium hydroxide, wherein the tetraalkyl ammonium oxide is defined by the following formula: (CnH2n + 1) 4NOH wherein 5 >; n > 1. Preferably, tetramethylammonium hydroxide is used in the practice of the invention. The catalyst can be made from any suitable organic or inorganic precursor compound of V and Sb, and the compounds used to introduce other optional elements into the final catalyst after calcination, as is well known in the art, such as salts , oxides, hydroxides or etalo-organic compounds of these elements, with the tin that is introduced to the batch of the starting materials to prepare these catalysts in the form of a solution of Sn? 2"xH0, dispersed in tetraalkyl ammonium hydroxide As previously described herein, the mixture of the batch of the precursor materials is heated and calcined in a known manner until the final catalyst results.The examples of these starting source batch materials are, of course, shown in the specific work examples in this one, particularly effective procedures for E-1049/98 X the catalyst manufacture are disclosed in US Pat. Nos. 4,879,264, 3,860,534 and 5,094,989, incorporated herein by reference. In addition, the catalyst can optionally be treated by one or more of the methods described in US Pat. Nos. 5,432,141 and 5,498,588, also incorporated herein by reference. In the preparation of the catalysts of the present invention, the upper calcination temperature is usually at least 500 ° C, but for the ammoxidation of the paraffthis temperature is preferably more than 750 ° C, frequently more than 780 ° C. The catalyst can be supported or not supported in a suitable carrier. Preferably, the catalyst is supported in a carrier such as silica, alumina, silica-alumina, zirconia or mixtures thereof. A preferred method of the invention is to make catalysts having elements and the proportions indicated by the empirical formula: VSbmAaDdOx where A is one or more of Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca, Sr, Ba, Co, Faith, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, E'1049 / q8MX Ta, Se, Bi, Ce, In, As, B, Al and Mn where m is 0.5 to 10 a is greater than zero at 10 d is zero at 10 x is determined by the oxidation state of the cations present, comprising the preparation of an aqueous slurry of a mixture of the source batch materials, comprising the compounds of the elements to be included in the final catalyst, followed by the drying and calcination with heat of the mixture to give an active catalyst, wherein the source batch material for the tin is a solution comprising Sn0 .xH20, wherein x > 0, dispersed in tetraalkyl ammonium hydroxide, wherein the tetraalkyl ammonium hydroxide is defined by the following formula: (CnH2n + 1) 4N0H wherein 5 > n > 1, drying the suspension and calcining the mixture at a higher calcination temperature of at least 780 CC. The upper calcination temperature can be up to 1200 ° C, but frequently it is no more than 1050 ° C. In another aspect of the present invention; a process is provided for making an α, β-unsaturated mononitrile, selected from acrylonitrile and E'104 9 / Í > 8MX methacrylonitrile, by the catalytic vapor phase reaction of a paraffin, selected from propane and isobutane, with molecular oxygen and ammonia and, optionally, a gaseous diluent, by catalytic contact of the above reagents in a reaction zone with a catalyst , the feed to the reaction zone contaa molar ratio of the paraffin to NH3 in the range of 2.5 to 16 (preferably from 4 to 12, especially preferred from 5 to 11) and a molar ratio of the paraffin to 02 in the interval from 1 to 10 (preferably from 2 to 9, especially from 3 to 9), the catalyst has an empirical composition mentioned in the last previous paragraph, the catalyst is prepared by the method of the last previous paragraph. The catalyst can also be used in the ammoxidation of methylpyridine and m-xylene to give cyanopyridine and isophthalonitrile or the oxidation of o-xylene to give phthalic anhydride. The molar ratios of NH3 to methylpyridine and 02 to methylpyridine are from 1 to 5 and from 1 to 10, respectively. The molar ratios of NH3 to m-xylene and 02 to m-xylene are from 1 to 5 and from 1 to 10, respectively. In the phthalic anhydride reaction, the ratio of 02 to o-xylene can vary from 1 to 10. The catalyst prepared by the process of the present invention can also be used in the E'1049 / ') 8MX Amoxidation of propylene or isobutene with ammonia and oxygen to produce acrylonitrile or methacrylonitrile. The molar ratio of NH3 to olefin can vary from about 1 to 5 and the molar ratio of 02 to olefin can vary from 1 to 10 in this reaction, low at conventional temperatures and conditions well known in the art.

DETAILED DESCRIPTION OF THE INVENTION The following description of the preparation of the catalysts and the ammoxidation reactions using the catalysts prepared in this manner are exemplary only and should not be understood in any sense as limiting.

Example 1 A catalyst having the composition VSbx .4Sm0 _2TiQ was prepared. Ox (Catalyst No. 17388-79), by mixing 27.30 g of the V205 powder, with a solution consisting of 100 ml of 30% H202 in 900 ml of water, in a two-liter beaker. After the reaction of the V205 powder is finished, 61.25 g of Sb203 followed by 2.40 g of Ti02 powder (Degussa P-25) are added. The beaker was covered with a watch glass and the mixture was stirred and heated during E'1049 / 98MX approximately 3 hours. In a separate beaker, 10.13 g of Sn02.xH20 ("acid tin oxide" Magnesium Elektron Inc., received on 6/7/91) were added to 100 ml of water and 8 ml of 25% by weight solution. of tetramethylammonium hydroxide. The mixture was heated on a hot plate with constant stirring until a translucent mixture formed. This dispersion containing tin was then added to the dispersion of vanadium, antimony, titanium above. The mixture was stirred in an open beaker, with heating, in order to reduce the volume by evaporation of water. When the mixture could not be stirred any longer, it was dried in an oven at 120 ° C. Subsequently, it was calcined for 1 hour at 325 ° C and then for 8 hours at 650 ° C, then cooled and crushed and sieved and then 25-35 mesh particles were collected. A portion of this was calcined for 3 hours at 820 ° C, then at 650 ° C for 3 additional hours. The calcined catalyst was then contacted with isobutanol using approximately 6.25 ml of isobutanol per gram of catalyst, by placing the catalyst in a thick glass frit funnel, pouring the isobutanol over the catalyst, stirring the catalyst in the isobutanol in order to extend the catalyst evenly over the bottom of the funnel, then let the isobutanol pass through the funnel without E > 104 9 / 98MX suction. This washing was done for a total of three times. After the last of the isobutanol passed through the funnel, the catalyst was heated in an oven at 120 ° C to remove the residual isobutanol in the catalyst. The catalyst was evaluated for the ammoxidation of propanol using a fixed-bed reactor in a U-tube, in 1/4 inch titanium. The reactor access feed had a molar ratio of 3 propane / l ammonia / 2 oxygen / 5 nitrogen at a pressure of 15 psig. At a reactor temperature of 490 ° C and a contact time of 1.4 seconds, the selectivity to acrylonitrile was 61.2% with a propane conversion of 19.2%. At a reactor temperature of 495 ° C and a contact time of 1.4 seconds, the selectivity to acrylonitrile was 58.6% with a propane conversion of 21.2%.

Example 2 The catalyst of the composition VSbx.xSno ^ Tio.iOx was prepared by mixing 27.30 g of V205 powder with a solution consisting of 100 ml of 30% H202 in 900 ml of water in a beaker of two. liters. After the reaction of the V05 powder was finished, 61.25 g of Sb203 followed by 2.40 g of Ti02 powder (Degussa P-25) were added. The beaker was covered with E'1049 / 98MX a watch glass and the mixture was stirred and heated for about 3 hours. In a separate beaker, 10.13 g of Sn02 * xH20 ("acid tin oxide") Magnesium Elektron Inc., received on 6/7/91), were added to 100 ml of water and 30 ml of 25% solution. by weight of tetramethylammonium hydroxide. The mixture was heated on a hot plate with constant stirring until a translucent mixture formed. This tin-containing dispersion was then added to the above dispersion of vanadium, antimony, titanium. The mixture was stirred in an uncovered beaker, with heating, in order to reduce the volume by the evaporation of the water. When the mixture could not be stirred any longer, it was dried in an oven at 120 ° C. Subsequently, it was calcined for 1 hour at 325 ° C, then for 8 hours at 650 ° C, then cooled and crushed and sieved and then the 20-35 mesh particles were collected. A portion of this was calcined for 3 hours at 820 ° C then at 650 ° C for an additional 3 hours. The calcined catalyst was then contacted with isobutanol using 6.25 ml of isobutanol per gram of catalyst by placing the catalyst in a thick glass frit funnel, pouring the isobutanol over the catalyst, stirring the catalyst in isobutanol in order to extend the catalyst evenly on the background E'1049 / 98MX of the funnel, then allowing the isobutanol to pass through the funnel without suction. This washing was done for a total of three times. After the last of the isobutanol was passed through the funnel, the catalyst was heated in a 120 ° oven to remove the residual isobutanol in the catalyst. The catalyst was evaluated for the ammoxidation of propane using a fixed bed reactor in the form of a 1/4 inch titanium U-tube. The gaseous feed to the reactor had a molar ratio of 3 propane / l ammonia / 2 oxygen / 5 nitrogen at a pressure of 15 psig. At a reactor temperature of 495 ° C and a constant time of 2.4 seconds, the selectivity to acrylonitrile was 55.6% with a propane conversion of 13.1%.

E 049 / 98MX

Claims (18)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, what is claimed as property is contained in the following CLAIMS t 1. A method for making a catalyst containing vanadium, antimony and tin, in the oxide state, which comprises making an aqueous slurry of a mixture of source batch materials comprising the compounds of the elements to be included in the final catalyst, drying the mixture and calcining the mixture to form an active catalyst, in where the source batch material for tin is a solution comprising, Sn02 * xH20 where x > 0 dispersed from the tetraalkyl ammonium hydroxide, wherein the tetraalkyl ammonium hydroxide is defined by the following formula: (CnH2n + 1) 4NOH wherein 5 > n > The method according to claim 1, wherein the Sn0 'xH20 is dispersed in tetraalkylammonium hydroxide 3. The process according to claim 1, wherein the calcination is at a temperature of at least 500 ° C. 4. The process according to claim 3, in E'1049 / 98MX where the ammoxidation or calcination of the paraffins at this temperature is at least 750 ° C. 5. The process according to claim 3, wherein the calcination temperature is at least 780 ° C. 6. The method according to claim 1, wherein the catalyst is supported in an inert carrier. The method according to claim 6, wherein the. carrier is selected from the group consisting of silica, alumina, silica-alumina, zirconia or mixtures thereof. 8. A method for preparing a catalyst having the elements and proportions indicated by the following empirical formula: VSbmAaDd0x where A is one or more of Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca , Sr, Ba, Co, Faith, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, Ace, B, Al and Mn where m is 0.5 to 10 a is greater than zero to 10 d is zero to 10 x is determined by the oxidation state of the cations present, E-1049 / 98MX comprising making an aqueous slurry of a mixture of the source batch materials comprising the compounds of the elements to be included in the final catalyst, followed by drying and heat-calcination of the mixture to obtain an active catalyst, wherein the source batch material for tin is a solution comprising Sn02 * xH20, wherein x > 0 dispersed in tetraalkyl ammonium hydroxide, wherein the tetraalkyl ammonium hydroxide is defined by the following formula: (CnH2n +?) 4N0H wherein 5 > n > 1, dry the slurry and calcined the mixture at a higher calcination temperature of at least 500 ° C. The method according to claim 8, wherein the calcination temperature is at least 750 ° C. The method according to claim 9, wherein the calcination temperature is at least 780 ° C. The method according to claim 8, wherein the catalyst is supported in an inert carrier. The method according to claim 11, wherein the inert carrier is selected from the group consisting of silica, alumina, zirconia, silica-alumina or mixtures thereof. The method according to claim 8, wherein the Sn02 * xH20 is dispersed in tetraalkylammonium hydroxide. P1049 / 98MX 14. A process for making an α, β-unsaturated mononitrile selected from acrylonitrile and methacrylonitrile; by the catalytic reaction in vapor phase of a paraffin selected from propane and isobutane with molecular oxygen and ammonia, by catalytic contact of the above reagents in a reaction zone with a catalyst having the following formula: VSbmAaDdOx where A is one or more than Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca, Sr, Ba, Co, Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu , Te, Ta, Se, Bi, Ce, In, As, B, Al and Mn where m is 0.5 to 10 a is greater than zero to 10 d is zero to 10 x is determined by the oxidation state of the cations present, the feed to the reaction zone contains a molar ratio of paraffin to NH3 in the range of 2.5 to 16 and a molar ratio of paraffin to 02 in the range of 1 to 10, wherein the catalyst has been prepared by the method of claim 1. E'1049 / 98MX 15. A process for making an α, β-unsaturated mononitrile, selected from acrylonitrile and methacrylonitrile, by the catalytic vapor phase reaction of a paraffin selected from propane and isobutane, with molecular oxygen and ammonia, by catalytic contact of the above reagents in a reaction zone with a catalyst having the following formula: VSbmAaDdOx where A is one or more of Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca, Sr, Ba, Co , Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, Ace, B, Al and Mn where m is from 0.5 to 10 a is greater than zero to 10 d is zero to 10 x is determined by the oxidation state of the cations present, the feed to the reaction zone contains a molar ratio of paraffin to NH3 in the range of 2.5 to 16 and a ratio molar of the paraffin to 02 in the range from 1 to 10, wherein the catalyst has been prepared by the method claimed ion 8. E'1049 / c) 8MX 16. A process for making a compound selected from the group consisting of cyanopyridine and isophthalonitrile by the catalytic reaction in the vapor phase of a starting material selected from the group consisting of methylpyridine and m-xylene with molecular oxygen and ammonia by the Catalytic contact of the above reagents in a reaction zone with a catalyst having the following formula: VSbmAaDdOx where A is one or more of Ti, Sn, where Sn is always present is one or more of Li, Mg, Ca, Sr, Ba, Co, Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, Ace, B, Al and Mn where m is from 0.5 to 10 a is greater than zero to 10 d is zero to 10 x is determined by the oxidation state of the cations present, the feed to the reaction zone containing a molar ratio of NH3 to the starting material in the range of 1 to 5 in a molar ratio of 02 to the starting material in the range of 1 to 10, wherein the catalyst it has been prepared by the method of claim 1. E'1049 / 98MX 17. A process for preparing phthalic anhydride from o-xylene by the catalytic vapor phase reaction of o-xylene with molecular oxygen, by catalytic contact of the above reagents in a reaction zone with a catalyst having the following formula: VSbmAaDdOx where A is one or more of Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca, Sr, Ba, Co, Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, As, B, Al and Mn where m is 0.5 to 10 a is greater than zero to 10 d is zero to 10 x is determined by the Oxidation state of the cations present, the feed to the reaction zone contains a molar ratio of 02 to o-xylene in the range of 1 to 10, wherein the catalyst has been prepared by the method of claim 1. 18. A process for making an α, β-unsaturated mononitrile selected from acrylonitrile and methacrylonitrile by the catalytic reaction in the vapor phase of an olefin a selected from propylene and P1049 / 98MX Isobutene with ammonia and an oxygen-containing gas, by catalytic contact of the above reagents in a reaction zone with a catalyst having the following formula: VSbmAaDd0x where A is one or more of Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca, Sr, Ba, Co, Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, As, B, Al and Mn where m is 0.5 to 10 is greater than zero to 10 is zero to 10 x is determined by the oxidation state of the cations present, the feed to the reaction zone that contains an ammonia to olefin molar ratio in the range of 1 to 5, a molar ratio of oxygen to olefin in the range of 1 to 10, wherein the catalyst has been prepared by the method of claim 1. E 049 / 98MX SUMMARY OF THE INVENTION A method for preparing a catalyst having the elements and proportions indicated by the following empirical formula: VSbmAaDdOx where A is one or more of Ti, Sn, where Sn is always present D is one or more of Li, Mg, Ca, Sr, Ba, Co, Fe, Cr, Ga, Ni, Zn, Ge, Nb, Zr, Mo, W, Cu, Te, Ta, Se, Bi, Ce, In, As, B, Al and Mn where m is 0.5 to 10 a is greater than zero at 10 d is zero at 10 x is determined by the oxidation state of the cations present, which comprises making an aqueous slurry of a mixture of the source batch materials, comprising the compounds of the elements to be included in the final catalyst, followed by drying and calcining with heat of the mixture to obtain a catalyst active, where the source batch material for tin is a solution comprising Sn02 * xH20, where x >; 0 dispersed in tetraalkyl ammonium hydroxide, where the hydroxide E49 / 98MX of tetraalkyl ammonium is defined by the following formula: (CnH2n + 1) 4NOH wherein 5 > n > 1, dry the slurry and calcined the mixture at a calcination temperature higher than at least 500 ° C. E'1049 / 98MX