Direct epoxidation process using modifiers
The invention is a process for epoxidizing an olefin with hydrogen and oxygen in a solvent comprising tertiary butyl alcohol or acetonitrile in the presence of an amide modifier and a catalyst comprising titanium-MWW zeolite and a noble metal. The process produces less ring-opened products such as glycols and glycol ethers when performed in the presence of the amide, while maintaining low alkane byproduct formed by the hydrogenation of olefin.
1 . A process for producing an epoxide, which comprises reacting an olefin, oxygen, and hydrogen in a solvent comprising tertiary butyl alcohol or acetonitrile in the presence of an amide modifier and a catalyst comprising a titanium-MWW zeolite and a noble metal.
2 . The process of claim 1 wherein the catalyst contains 0.01 to 10 weight percent of the noble metal and 0.001 to 5 weight percent of an additional metal selected from the group consisting of lead, bismuth, and rhenium.
3 . The process of claim 1 wherein the noble metal is palladium.
4 . The process of claim 1 wherein the noble metal is supported on the titanium-MWW zeolite.
5 . The process of claim 1 wherein the noble metal is supported on a carrier.
6 . The process of claim 5 wherein the carrier is selected from the group consisting of carbon, titania, zirconia, niobia, silica, alumina, silica-alumina, tantalum oxide, molybdenum oxide, tungsten oxide, titania-silica, zirconia-silica, niobia-silica, and mixtures thereof.
7 . The process of claim 1 wherein the olefin is a C 2 -C 6 olefin.
8 . The process of claim 1 wherein the amide modifier is selected from the group consisting of urea, formamide, and acetamide.
9 . The process of claim 1 wherein the solvent further comprises water.
10 . A process for producing propylene oxide comprising reacting propylene, hydrogen and oxygen in a solvent comprising tertiary butyl alcohol or acetonitrile in the presence of an amide modifier and a catalyst comprising a titanium-MWW zeolite and palladium.
11 . The process of claim 10 wherein the catalyst contains 0.01 to 10 weight percent of palladium and 0.001 to 5 weight percent of lead.
12 . The process of claim 10 wherein the palladium is supported on the titanium-MWW zeolite.
13 . The process of claim 10 wherein the noble metal is supported on a carrier selected from the group consisting of carbon, titania, zirconia, niobia, silica, alumina, silica-alumina, tantalum oxide, molybdenum oxide, tungsten oxide, titania-silica, zirconia-silica, niobia-silica, and mixtures thereof.
14 . The process of claim 10 wherein the amide modifier is selected from the group consisting of urea, formamide, and acetamide.
15 . The process of claim 10 wherein the solvent further comprises water.