Claims
- 1. A method for producing a catalyst comprising subjecting a silica-containing support at an elevated temperature to a treating ambient selected from (1) .[.carbon monoxide, (2).]. a halogen-containing component selected from bromide, iodine, HBr, HI, organic bromides, and organic iodides, which halogen-containing component also either contains air or is followed by air or .[.(3).]. .Iadd.(2) .Iaddend.a carbon, oxygen and sulfur-containing composition, thereafter incorporating a chromium compound under anhydrous conditions to thus form said catalyst and thereafter activating said catalyst in an oxygen ambient.
- 2. A method according to claim 1 wherein after said incorporation of said chromium compound said catalyst is activated in an oxygen ambient at a temperature within the range of 15.degree.-870.degree. C. for a time of at least 5 minutes.
- 3. A method according to claim 1 wherein said silica is a coprecipitated silica-titania cogel.
- 4. A method according to claim 1 wherein said chromium is incorporated in an amount sufficient to give 0.1 to 5 weight percent chromium based on the weight of said support.
- 5. A method according to claim 1 wherein said support is a silica-titania cogel containing 0.5 to 5 weight percent titanium based on the weight of said cogel. tion conditions after being subjected to said ambient and prior to incorporation of said chromium compound.
- 6. A method according to claim 1 wherein said chromium compound is incorporated by means of an inert liquid hydrocarbon diluent or solvent.
- 7. A method according to claim 1 wherein said support is preoxidized by being subjected to oxidation conditions after being subjected to said ambient and prior to incorporation of said chromium compound.
- 8. A catalyst produced by the method of claim 1. .[.9. A method according
- to claim 5 wherein said treating ambient is carbon monoxide..]. 10. A method according to claim 5 wherein said treating ambient is bromine
- vapor. 11. A method according to claim 5 wherein said treating ambient is
- HBr. 12. A method according to claim 5 wherein said treating ambient is
- bromine+air. 13. A method according to claim 5 wherein said treating
- ambient is iodine vapor. 14. A method according to claim 5 wherein said
- treating ambient is HI. 15. A method according to claim 5 wherein said
- treating ambient is iodine+air. 16. A method according to claim 5 wherein said treating ambient is said halogen-containing component of .[.(2).]. .Iadd.(1) .Iaddend.and wherein said halogen-containing component is bromine and wherein said ambient contains in addition carbon monoxide.
- A method according to claim 5 wherein said treating ambient is said halogen-containing component of .[.(2).]. .Iadd.(1) .Iaddend.and wherein said halogen-containing component is iodine and wherein said ambient
- contains in addition carbon monoxide. 18. A method according to claim 5
- wherein said treating ambient is carbonyl sulfide. 19. A method according to claim 5 wherein said elevated temperature is within the range of
- 750.degree.-925.degree. C. 20. A method according to claim 6 wherein said chromium compound is one of .pi.-bonded organochromium compound, esters of
- chromic acid, and chromium acetylacetonate. 21. A method according to claim 7 wherein said support is a silica-titania cogel containing about 2 weight percent titanium, said elevated temperature is within the range of 750.degree.-925.degree. C., said chromium compound is selected from tertiary butyl chromate, and dicumene chromium carried in normal hexane, and wherein said preoxidation is carried out at a temperature within the range of 525.degree.-925.degree. C., and wherein after said incorporation of said chromium compound said catalyst is activated by heating in air at
- a temperature within the range of 315.degree.-760.degree. C. 22. A
- catalyst produced by the method of claim 21. 23. A method for producing an iodinated or brominated silica comprising subjecting a silica-containing composition at a temperature within the range of 500.degree.-1000.degree. C. under reducing conditions to a treating ambient selected from at least one of (a) elemental iodine or elemental bromine plus a reducing agent;
- (b) HI or HBr or (c) an organic iodide or organic bromide. 24. A method according to claim 23 wherein said treating ambient comprises 0.1 to 10 mole percent of iodine or bromine, the remainder being said reducing
- agent, said reducing agent comprising carbon monoxide. 25. A method according to claim 24 wherein said elevated temperature is within the
- range of 750.degree.-925.degree. C. 26. A method according to claim 24 wherein said treating ambient consists essentially of iodine vapor plus
- CO. 27. A method according to claim 24 wherein said treating agent
- consists essentially of bromine plus carbon monoxide. 28. A composition comprising silica containing 0.01-20 weight percent of a halogen selected from bromine and iodine based on the weight of said silica, said composition being further characterized by said halogen being bound
- directly to silicon atoms. 29. A composition according to claim 28 wherein said halogen is iodine and is present in an amount within the range of
- 3-10 weight percent based on the weight of said silica. 30. A composition according to claim 28 wherein said halogen is bromine and is present in an amount within the range of 3-10 weight percent based on the weight of said
- silica. 31. A composition according to claim 29 wherein said silica is
- produced by coprecipitating silica and titanium. 32. A composition comprising silica containing 0.001 to 1 millimoles of a halogen selected from bromine and iodine per 100 square meters of surface area of said silica, said composition being further characterized by said halogen being
- bound directly to silicon atoms. 33. A composition according to claim 32 containing 0.03 to 0.3 millimoles of said halogen per 100 square meters of
- surface area of said silica. 34. A composition according to claim 32 wherein said silica is produced by coprecipitating silica and titanium.
- A composition according to claim 32 further characterized by said
- halogen not coming off at 871.degree. C. in CO or N.sub.2. 36. A
- composition according to claim 32 wherein said halogen is iodine. 37. A
- composition according to claim 32 wherein said halogen is bromine. 38. A composition comprising silica containing 0.01-20 weight percent of a halogen selected from bromine and iodine based on the weight of said silica, said composition being further characterized by said halogen not
- coming off at 871.degree. C. in CO or N.sub.2. 39. A composition according
- to claim 38 wherein said halogen is iodine. 40. A composition according to
- claim 38 wherein said halogen is bromine. 41. A method of making a free radical containing silica composition comprising subjecting a silica-containing composition at a temperature within the range of 500.degree.-1000.degree. C. under reducing conditions to a treating ambient selected from (a) elemental iodine plus a reducing agent; (b) HI or (c) an organic iodide and thereafter treating the resulting halogen-containing silica in an oxygen-containing ambient to burn off
- surface halogen. 42. A method according to claim 41 wherein said treatment
- to burn off surface halogen is carried out in air. 43. A silica
- composition produced by the method of claim 41. 44. A method according to claim 42 wherein said treatment to burn off surface halogen is carried out at a temperature within the range of 525.degree.-925.degree. C. for a long
- time within the range of 1 to 5 hours. 45. A method according to claim 42 wherein said treating ambient is elemental iodine plus carbon monoxide.
- A method according to claim 42 wherein said silica is a silica-titania
- cogel containing about 2 weight percent titanium. 47. A composition according to claim 43 having an ESR g value within the range of 1.8 to
- 2.2. 48. A composition according to claim 43 wherein said silica is a silica-titania containing cogel containing about 2 weight percent titanium. .Iadd. 49. A method for producing a catalyst comprising subjecting a silica-titania cogel support at an elevated temperature to a treating ambient comprising carbon monoxide, thereafter incorporating a chromium compound under anhydrous conditions to thus form said catalyst and thereafter activating said catalyst in an oxygen ambient. .Iaddend..Iadd. 50. A catalyst produced by the method of claim 49. .Iaddend..Iadd. 51. A method for producing a catalyst comprising subjecting a silica-containing support at an elevated temperature to a treating ambient comprising carbon monoxide to produce a treated support, thereafter preoxidizing said treated support by subjecting said treated support to oxidation conditions, thereafter incorporating a chromium compound under anhydrous conditions to thus form said catalyst and thereafter activating said catalyst in an oxygen ambient. .Iaddend..Iadd. 52. A catalyst produced by the method of claim 51. .Iaddend.
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of copending application Ser. No. 857,552, filed Dec. 5, 1977, now abandoned.
US Referenced Citations (14)
Foreign Referenced Citations (3)
Number |
Date |
Country |
863932 |
Feb 1971 |
CAX |
2278710 |
Feb 1976 |
FRX |
1415646 |
Nov 1975 |
GBX |
Non-Patent Literature Citations (2)
Entry |
Infrared Study of OH & NH.sub.2 Groups on the Surface of a Dry Silica Aerogel, J. B. Peri, vol. 70, #9, 1966, The Journal of Physical Chemistry, pp. 2937-2945. |
Chem. Abstracts, vol. 83, 1975, ref. 59929b, p. 50, Zakharov et al., Cat. for poly of ethylene. |
Continuation in Parts (1)
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857552 |
Dec 1977 |
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Reissues (1)
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044809 |
Jun 1979 |
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