Claims
- 1. In a process for oxidizing a hydrocarbon to maleic anhydride by contact with molecular oxygen, in the presence of a catalyst, the improvement comprising:
- employing in the oxidizing a mixed oxide catalyst comprising vanadium, phosphorus and a member selected from the group consisting of aluminum, boron and mixtures thereof, said catalyst having a phosphorus to vanadium atomic ratio, based on phosphorus uncombined with said member, of from 1:1 to 2:1, and atomic ratio of said member to vanadium of at least 0.10:1, said catalyst having been prepared by treating dried solid catalyst precursor comprising mixed oxides of vanadium and phosphorus, in finely divided form, with a solution of phosphoric acid and a member selected from the group consisting of water soluble compounds of aluminum, boron and mixtures thereof, and drying of the treating solid catalyst precursor to provide a solid catalyst.
- 2. The process of claim 1 wherein the finely divided catalyst precursor has an average particle size of less than 10 microns.
- 3. The process of claim 2 wherein said member is boron.
- 4. The process of claim 3 wherein at least a portion of the catalyst precursor prior to treatment has been calcined to remove water of hydration and provide a partial oxidation of vanadium to the pentavalent state.
- 5. The process of claim 3 wherein uncalcined dried catalyst precursor, in finely divided form, is subjected to the treatment.
- 6. The process of claim 3 wherein the dried catalyst precursor, in finely divided form, which is subjected to treatment is a mixture of calcined and uncalcined catalyst precursor, the ratio of calcined to uncalcined catalyst precursor in such mixture being from 10:1 to 1:10.
- 7. The process of claim 6 wherein the ratio of boron to vanadium is no greater than 0.25:1.
- 8. The process of claim 6 wherein the dried catalyst has an average particle size of at least 40 microns.
- 9. The process of claim 2 wherein the catalyst precursor, in finely divided form, which is subjected to treatment is a mixture of calcined and uncalcined catalyst precursor, wherein the ratio of calcined precursor to uncalcined precursor is from 10:1 to 1:10.
- 10. The process of claim 9 wherein the dried catalyst is in microspherical form, and has are average particle size of from 40 to 200 microns.
- 11. The process of claim 10 wherein the catalyst has a phosphorus to vanadium ratio, based on phosphorus uncombined with said member of from 1:1 to 1.3:1.
- 12. The process of claim 1 wherein the oxidizing is effected in a fluidized bed of said mixed oxides catalyst.
- 13. The process of claim 12 wherein the hydrocarbon is butane.
- 14. The process of claim 12 wherein the oxidizing temperature is from 320.degree. C. to 500.degree. C.
- 15. The process of claim 12 wherein the finely divided catalyst precursor has an average particle size of less than 10 microns.
- 16. The process of claim 15 wherein the dried catalyst precursor, in finely divided form, which is subjected to treatment is a mixture of calcined and uncalcined catalyst precursor, the ratio of calcined to uncalcined catalyst precursor in such mixture being from 10:1 to 1:10.
- 17. The process of claim 16 wherein said member is boron, and the ratio of boron to vanadium is no greater than 0.25:1.
- 18. The process of claim 17 wherein the dried catalyst is in microspherical form, and has an average particle size of from 40 to 200 microns.
- 19. The process of claim 18 wherein the catalyst has a phosphorus to vanadium ratio, based on phosphorus uncombined with boron of from 1:1 to 1.3:1.
Parent Case Info
This is a division of application Ser. No. 583,769, filed 8-17-83 now U.S. Pat. No. 4,511,670.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
4386215 |
Mount et al. |
May 1983 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
523769 |
Aug 1983 |
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