Claims
- 1. A process for epoxidizing an olefin comprising contacting the olefin with a source of hydrogen peroxide in the presence of a catalytically effective amount of a crystalline siliceous molecular sieve zeolite having niobum substituted in the zeolite framework structure and characterized by the substantial absence of exchangeable cations.
- 2. The process of claim 1 wherein the olefin is a C.sub.2 -C.sub.10 mono-olefin.
- 3. The process of claim 1 wherein said contacting is performed at a temperature of from 20.degree. C. to 100.degree. C.
- 4. The process of claim 1 wherein the crystalline siliceous molecular sieve zeolite has an anhydrous formula in terms of molar ratios of oxide corresponding to xNb.sub.2 O.sub.5.(1-x)SiO.sub.2 where x is from 0.0005 to 0.1.
- 5. The process of claim 1 wherein the crystalline siliceous molecular sieve zeolite has a zeolite framework structure isomorphous with ZSM-5.
- 6. The process of claim 1 wherein the crystalline siliceous molecular sieve zeolite is characterized by the substantial absence of aluminum.
- 7. The process of claim 1 wherein a solvent is additionally present during said contacting.
- 8. A process for epoxidizing a C.sub.2 -C.sub.10 mono-olefin comprising contacting the C.sub.2 -C.sub.10 mono-olefin with a source of hydrogen peroxide at a temperature of from 20.degree. C. to 100.degree. C. in the presence of a catalytically effective amount of a crystalline siliceous molecular sieve zeolite having niobium substituted in a zeolite framework structure isomorphous with ZSM-5 and characterized by the substantial absence of aluminum and exchangeable cations and having an anhydrous formula in terms of molar ratios of oxide corresponding to xNb.sub.2 O.sub.5.(1-x)SiO.sub.2 where x is from 0.0005 to 0.1.
- 9. The process of claim 8 wherein the C.sub.2 -C.sub.10 mono-olefin is propylene.
- 10. The process of claim 8 wherein a solvent is additionally present during said contacting.
- 11. A process for epoxidizing an olefin comprising contacting the olefin with a source of hydrogen peroxide in the presence of a catalytically effective amount of a crystalline siliceous molecular sieve zeolite having niobium substituted in the zeolite framework structure and characterized by the substantial absence of exchangeable cations and obtained by a method comprising:
- (a) forming a mixture of a hydrolyzable silicon compound, a hydrolyzable niobium compound, and a quaternary ammonium species; and
- (b) subjecting said mixture to hydrothermal treatment at a temperature of from 100.degree. C. to 200.degree. C. for a time effective to form the crystalline siliceous molecular sieve zeolite.
- 12. The process of claim 11 wherein the method comprises an additional step of calcining at a temperature in excess of 400.degree. C.
- 13. The process of claim 11 wherein the quaternary ammonium species is tetrapropyl ammonium hydroxide.
- 14. The process of claim 11 wherein the hydrolyzable silicon compound is a tetraalkoxysilane.
- 15. The process of claim 11 wherein the hydrolyzable niobium compound is a niobium alkoxide.
Parent Case Info
This is a division of application Ser. No. 08/565,711, filed Nov. 30, 1995 now U.S. Pat. No. 5,618,512.
US Referenced Citations (4)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0178723 |
Mar 1985 |
EPX |
4349115 |
Feb 1992 |
JPX |
Non-Patent Literature Citations (2)
Entry |
"Synthetic & Mechanistic Aspects of Metal-Catalysed Ephirlatians with Hydropexorules", R.A. Sheldon, Journal of Molecular Catalysis 7 (1980) 107 & 126. |
"Transition-Metal-Catalyzed Epoxidations", K. Jorgensen, Chemical Reviews 89 3 (May 1989). |
Divisions (1)
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Number |
Date |
Country |
Parent |
565711 |
Nov 1995 |
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