Peptized and phosphated inorganic oxides and catalysts supported on said oxides

• US 4,900,704 A
• Filed: 09/29/1988
• Issued: 02/13/1990
• Est. Priority Date: 09/29/1988
• Status: Expired due to Fees

• Current Assignee: Phillips Petroleum Company (ConocoPhillips)
• Original Assignee: Phillips Petroleum Company (ConocoPhillips)
• Inventors: Farha, Floyd E. Jr., McDaniel, Max P., Pitzer, Emory W.
• Primary Examiner(s): Shine, W. J.
• Application Number:
  US07/250,589
• Time in Patent Office: 502 Days
• Field of Search: 502/208, 502/210, 502/439, 423/308, 423/309, 423/311
• US Class Current: 502/210
• CPC Class Codes: C08F 10/00 Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• CPC Class Codes: C08F 4/02 Carriers therefor
• CPC Class Codes: C08F 4/22 of chromium, molybdenum or tungsten
• CPC Class Codes: C08F 4/78 selected from chromium, molybdenum or tungsten

Abstract

Fine, pure, boehmite alumina crystallites are peptized, partially precipitated and phosphated, hardened, and dried to form a zerogel. The alumina can be impregnated with a chromium compound. The chromium-containing catalyst is activated by calcination. The activated catalyst can be used as a polymerization catalyst to polymerize mono-1-olefins.

Claims

1. A process to make a phosphated alumina xerogel comprising:

(a) peptizing fine, pure, boehmite alumina crystallites with a peptizing agent selected from the group consisting of nitric acid, aluminum nitrate, and mixtures thereof to form a clear solution;

(b) adding a phosphating agent selected from the group consisting of phosphoric acid, ammonium phosphates, and mixtures thereof to said clear solution to form a partially precipitated, phosphated alumina;

(c) further hardening said partially precipitated, phosphated alumina by neutralizing the clear solution with a base selected from the group consisting of ammonia, ammonium hydroxide, alkyl ammonium hydroxides, amines, and mixtures thereof; and

(d) removing substantially all water from the thus further hardened precipitate to form a substantially water-free phosphated alumina xerogel.

2. A process according to claim 1 further comprising incorporating a chromium compound into said phosphated alumina xerogel.

3. A process according to claim 1 further comprising aging the thus further hardened precipitate at a temperature in the range of about 70°

C. to about 100°

C., for a time in the range of about one-half to about 7 hours, at a pH in the range of about 6 to about 8.

4. A process according to claim 1 wherein said peptizing agent is added in an amount sufficient to peptize substantially all of the alumina.

5. A process according to claim 1 wherein said phosphated alumina xerogel has a P/Al mole ratio in the range of about 0.05 to about 0.5.

6. A process according to claim 1 wherein said base is added in an amount sufficient to result in a pH in the range of about 6 to about 10.

7. A process according to claim 1 wherein substantially all water is removed by washing the further hardened precipitate with an aliphatic alcohol having from about 1 to about 4 carbon atoms.

8. A process according to claim 1 wherein substantially all water is removed by azeotrope drying.

9. A process according to claim 1 wherein substantially all water is removed by oven drying.

10. A process according to claim 1 wherein substantially all water is removed by spray drying.

11. A process according to claim 2 further comprising the step of heating the thus chromium impregnated xerogel at a temperature in the range of about 300°

to about 1000°

C., for a time in the range of about 30 minutes to about 50 hours, in an oxidizing atmosphere.

12. A catalyst support produced by the process of claim 1.

13. A catalyst produced by the process of claim 11.

14. A process to make a phosphated alumina xerogel comprising the steps of:

(a) peptizing fine, pure, boehmite alumina crystallites with a peptizing agent selected from the group consisting of nitric acid, aluminum nitrate, and mixtures thereof to form a clear solution;

(b) adding phosphoric acid to form a partially precipitated, phosphated alumina;

(c) further hardening said partially precipitated, phosphated alumina by neutralizing the clear solution with ammonium hydroxide;

(d) washing the thus further hardened phosphated alumina with isopropyl alcohol to form a substantially water-free precipitate; and

(e) drying the substantially water-free precipitate to form a xerogel.

15. A process according to claim 14 further comprising the step of incorporating a chromium compound into said xerogel.

16. A process according to claim 15 further comprising the step of heating the thus chromium impregnated xerogel at a temperature in the range of about 300°

to about 1000°

C., for a time in the range of about 30 minutes to about 50 hours, in an oxidizing atmosphere.

17. A catalyst support produced by the process of claim 14.

18. A catalyst produced by the process of claim 16.