Process for preparation of liquefied petroleum gas selective cracking catalyst

Abstract

The present invention relates to a cracking catalyst composition for cracking heavy hydrocarbon and processes for preparing the catalyst. The process can include treating zeolite with sodium free basic compound with or without phosphate, treating an alumina with a dilute acid, acidifying a colloidal silica, preparing a fine slurry of clay with a source of phosphate, adding alumina slurry and/or acidified colloidal silica to clay phosphate slurry, adding treated zeolite and spray-drying the slurry and calcining the same to obtain a cracking catalyst having adequate ABD and attrition resistance property.

Description

Claims

1. A process for preparing a cracking catalyst composition for cracking heavy hydrocarbon, comprising: treating a zeolite with a sodium free basic compound with or without phosphate, the resulting zeolite slurry having a pH between about 5 to about 9;treating an alumina with a dilute acid to obtain an alumina binder;preparing a clay slurry with a source of phosphate;combining the treated zeolite, the alumina binder, and the clay slurry to obtain a slurry mixture; andspray-drying and calcining the slurry mixture to obtain a cracking catalyst.

2. The process of claim 1, wherein the sodium free basic compound is ammonium hydroxide.

3. The process of claim 1, wherein the zeolite includes at least one of ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48, ZSM-57, Zeolite beta, and mordenite.

4. The process of claim 1, wherein the phosphate compound is selected from a group consisting of ammonium dihydrogen phosphate, ammonium monohydrogen phosphate, triammonium phosphate, ammonium hypophosphate, ammonium ortho-phosphate, ammonium dihydrogen ortho-phosphate, ammonium monohydrogen ortho-phosphate, ammonium hypophosphite, ammonium dihydrogen ortho-phosphite, and ortho-phosphoric acid.

5. The process of claim 1, wherein the alumina is selected from a group consisting of pseudoboehmite alumina, boehmite, aluminum trihydrate, bayrite alumina, and gamma alumina.

6. The process of claim 1, wherein the dilute acid for treating alumina is selected from a group consisting of nitric acid, hydrochloric acid, formic acid, and acetic acid.

7. The process of claim 1, wherein the colloidal silica is sodium and/or ammonium stabilized poly silicate.

8. The process of claim 1, wherein the colloidal silica having a pH between about 7.0 and about 11.5.

9. The process of claim 1, wherein colloidal silica is acidified to a pH between about 0.5 and about 3.5 before use.

10. The process of claim 1, wherein the acid used for acidifying colloidal silica is selected from a group consisting of nitric acid, hydrochloric acid, formic acid, and acetic acid.

11. The process of claim 7, wherein the colloidal silica includes silica particles having a mean diameter ranging between 4 to 30 nm.

12. The process of claim 7, wherein the colloidal silica has soda or ammonia in the range between about 0.1 to about 0.8 wt %.

13. The process of claim 1, wherein the zeolite slurry has phosphate content in the range of about 0 to about 20 wt % calculated on a volatile-free basis.

14. The process of claim 1, wherein the alumina has a soda content in the range of between about 0.001 and about 0.1 wt %.

15. The process of claim 1, wherein the clay is selected from a group consisting of kaolin, and halloysite.

16. The process of claim 1, wherein the phosphate source used for preparing the clay slurry includes ortho-phosphoric acid.

17. The process of claim 1, wherein the alumina includes pseudoboehmite.

18. The process of claim 1, wherein the zeolite includes ZSM-5.

19. The process of claim 1, wherein the acid used for acidifying colloidal silica includes formic acid.

20. A catalyst composition for cracking heavy residual hydrocarbon feed, comprising: treated high silica medium pore zeolite in the range of about 1 wt % to about 50 wt %;silica in the range of about 1 wt % to about 30 wt %;alumina in the range of about 1 wt % to about 30 wt %;clay in the range of about 10 wt % to about 50 wt %; andphosphate in the range about 1 wt % to about 20 wt %.

21. The catalyst of claim 20, wherein Zeolite is selected from a group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48, ZSM-57, Zeolite beta, mordenite.

22. The catalyst of claim 20, wherein the silica is colloidal silica includes ammonium and/or sodium stabilized poly silicate.

23. The catalyst of claim 20, wherein the particle size of silica is in the range of from about 4 nm to about 10 nm.

24. The catalyst of claim 20, wherein the alumina is selected from a group consisting of pseudoboehmite, boehmite, aluminum trihydrate, bayrite alumina, gamma alumina.

25. The catalyst of claim 20, wherein the clay is selected from kaolin, holloysite.

26. The catalyst of claim 20, wherein the phosphate is selected from a group consisting of ortho-phosphoric acid, ammonium dihydrogen phosphate, ammonium monohydrogen phosphate, triammonium phosphate, ammonium hypophosphate, ammonium ortho-phosphate, ammonium dihydrogen ortho-phosphate, ammonium monohydrogen ortho-phosphate, ammonium hypophosphite, ammonium dihydrogen ortho-phosphite.

27. The catalyst of claim 19, wherein the particle size of the catalyst is in the range of about 20-150 microns.

28. The catalyst of claim 19, wherein the particle size of the catalyst is in the range of about 30-100 microns.

29. A catalyst composition for cracking heavy hydrocarbon feed, comprising: treated high silica medium pore zeolite in the range of about 1 wt % to about 40 wt %;silica in the range of about 1 wt % to about 30 wt %;alumina in the range of about 1 wt % to about 30 wt %;clay in the range of about 10 wt % to about 50 wt %; andphosphate in the range about 1 wt % to about 20 wt %.