Dewaxing process using zeolites MTT and MTW
The present invention relates to the use of a combination of zeolites having the MTT and MTW framework topologies defined by the connectivity of their tetrahedral atoms wherein the MTT and MTW zeolites have a crystal size less than 0.1 micron as a catalyst in a process for dewaxing hydrocarbon feedstocks.
1 . A dewaxing process comprising contacting a hydrocarbon feedstock under dewaxing conditions with a catalyst comprising a combination of zeolites having the MTT and MTW framework topologies defined by the connectivity of their tetrahedral atoms wherein the MTT and MTW zeolites have a crystal size less than 0.1 micron.
2 . The process of claim 1 wherein the zeolites are predominantly in the hydrogen form.
3 . The process of claim 1 wherein the catalyst further comprises at least one Group VIII metal.
4 . The process of claim 1 wherein the feedstock is bright stock.
5 . The process of claim 1 wherein the feedstock is derived from a Fischer Tropsch process.
6 . A process for improving the viscosity index of a dewaxed product of waxy hydrocarbon feeds comprising contacting a waxy hydrocarbon feed under isomerization dewaxing conditions with a catalyst comprising a combination of zeolites having the MTT and MTW framework topologies defined by the connectivity of their tetrahedral atoms wherein the MTT and MTW zeolites have a crystal size less than 0.1 micron.
7 . The process of claim 6 wherein the zeolites are predominantly in the hydrogen form.
8 . The process of claim 6 wherein the catalyst further comprises at least one Group VIII metal.
9 . A process for producing a C 20+ lube oil from a C 20+ olefin feed comprising isomerizing said olefin feed under isomerization conditions over a catalyst comprising a combination of zeolites having the MTT and MTW framework topologies defined by the connectivity of their tetrahedral atoms wherein the MTT and MTW zeolites have a crystal size less than 0.1 micron.
10 . The process of claim 9 wherein the zeolites are predominantly in the hydrogen form.
11 . The process of claim 9 wherein the catalyst further comprises at least one Group VIII metal.
12 . A process for catalytically dewaxing a hydrocarbon oil feedstock boiling above about 350° F. and containing straight chain and slightly branched chain hydrocarbons comprising contacting said hydrocarbon oil feedstock in the presence of added hydrogen gas at a hydrogen pressure of about 15-3000 psi under dewaxing conditions with a catalyst comprising a combination of zeolites having the MTT and MTW framework topologies defined by the connectivity of their tetrahedral atoms wherein the MTT and MTW zeolites have a crystal size less than 0.1 micron.
13 . The process of claim 12 wherein the zeolites are predominantly in the hydrogen form.
14 . The process of claim 12 wherein the catalyst further comprises at least one Group VIII metal.
15 . A process for isomerization dewaxing a raffinate comprising contacting said raffinate in the presence of added hydrogen under isomerization dewaxing conditions with a catalyst comprising a combination of zeolites having the MTT and MTW framework topologies defined by the connectivity of their tetrahedral atoms wherein the MTT and MTW zeolites have a crystal size less than 0.1 micron.
16 . The process of claim 15 wherein the zeolites are predominantly in the hydrogen form.
17 . The process of claim 15 wherein the catalyst further comprises at least one Group VIII metal.
18 . The process of claim 15 wherein the raffinate is bright stock.
19 . A process for reducing the cloud point of a hydrocarbon feed comprising contacting a hydrocarbon oil feedstock which has a major portion boiling over 1000° F. with a catalyst system comprising a combination of a zeolite having MTT topology and a zeolite having MTW topology wherein the MTT and MTW zeolites have a crystal size less than 0.1 micron., and wherein at least a portion of said feedstock is converted.
20 . The process of claim 19 wherein the catalyst system further comprises a hydrogenation component.
21 . The process of claim 19 wherein the cloud point of the feedstock is reduced to not more than 10° C.
22 . The process of claim 20 wherein the hydrogenation component comprises a Group VIII metal.
23 . The process of claim 22 wherein the Group VIII metal is selected from platinum, palladium and mixtures thereof.
24 . The process of claim 19 wherein the process is a dewaxing process and wherein the contacting is conducted under dewaxing conditions.
25 . The process of claim 19 wherein the hydrocarbon oil is bright stock.
26 . The process of claim 19 wherein the hydrocarbon oil is derived from a Fischer-Tropsch wax.
27 . The process of claim 19 wherein the process is conducted in the presence of added hydrogen gas.
28 . The process of claim 19 wherein the MTT and MTW zeolites are aluminosilicates.
29 . The process of claim 19 wherein the MTT and MTW zeolites have a crystal size less than about 0.1 micron.