Claims
- 1. A process for dewaxing a wax-containing lube stock which comprises:
- dewaxing said lube stock with a fresh zeolite dewaxing catalyst, having a constraint index between 1 and 12, in an original catalyst dewaxing cycle, wherein prior to said original dewaxing cycle the fresh catalyst is pretreated in the presence of hydrogen gas with one or more low molecular weight aromatic hydrocarbon compounds selected from the group consisting of benzene, toluene, xylene, naphthalene and mixtures thereof at temperatures greater than 800.degree. F. and under conditions which deposit on the catalyst between 2 and 30% of coke, by weight of the catalyst;
- continuing said first catalytic dewaxing cycle to an end of cycle dewaxing reaction temperature of between 650.degree. to 680.degree. F. at which point said dewaxing catalyst is substantially deactivated; and
- regenerating said pretreated dewaxing catalyst by contacting the substantially deactivated catalyst with hydrogen and one or more low molecular weight aromatic hydrocarbon compounds selected from the group consisting of benzene, toluene, xylene, naphthalene or mixtures thereof at a temperature from 600.degree. to 1200.degree. F. to reactivate the catalyst.
- 2. The process as recited in claim 1, which further comprises using the reactivated catalyst in a subsequent dewaxing cycle.
- 3. The process as recited in claim 1, wherein the pretreatment step is conducted at temperatures greater than 900.degree. F.
- 4. The process as recited in claim 1, wherein the fresh catalyst is coked for 72 hours.
RELATED APPLICATION
This is a divisional of copending application Ser. No. 087,196, filed on Aug. 20, 1987 which is a continuation-in-part application of U.S. Ser. No. 937,951, filed Dec. 4, 1986, both now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (1)
Number |
Date |
Country |
7307241 |
Aug 1973 |
NLX |
Divisions (1)
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Number |
Date |
Country |
Parent |
87196 |
Aug 1987 |
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Continuation in Parts (1)
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Number |
Date |
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Parent |
937951 |
Dec 1986 |
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