Patent US4898674A successfully refreshed from Google Patents.
US4898674A
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US
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Solvent dewaxing process
Assignee: Texaco Inc
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Filing: 1988-03-24
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Granted: 1990-02-06
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Expires: 2008-03-24
Abstract
Abstract Solvent dewaxing of charge lubricating oil stocks requiring different ratios of methyl ethyl ketone to toluene is effected by adjusting the ratio of components in the dewaxing solvent by a membrane.
Inventors
- 👤 Mordechai Pasternak
- 👤 Tansukhlal G. Dorawala
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:11
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0081; B01D67/0093; B01D61/00; B01D61/36; B01D61/362; B01D71/00; B01D71/06; B01D71/30; B01D71/32; B01D71/76; B01D71/82; C; C10; C10G; C10G73/00; C10G73/02; C10G73/06
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
155 words
A process for treating a charge solution containing an organic oxygen-containing wax antisolvent and an aromatic hydrocarbon oil solvent in a charge ratio of organic oxygen-containing wax antisolvent to aromatic hydrocarbon oil solvent which comprises passing a charge solution containing an organic oxygen-containing wax antisolvent and an aromatic hydrocarbon oil solvent in a charge ratio of organic oxygen-containing wax antisolvent to aromatic hydrocarbon oil solvent into contact with, as non-porous pervaporation membrane, a high molecular weight ion exchange resin in membrane form having carbon atoms in the backbone bearing a pendant acid group which membrane has been contacted with as counter ion, a potassium salt or with a quaternary phosphonium salt containing hydrocarbyl groups; maintaining a pressure drop across said pervaporation membrane thereby forming (i) a retentate containing decreased content of oxygen-containing wax antisolvent; and recovering said retentate containing decreased content of oxygen-containing wax antisolvent and said permeate containing increased content of oxygen-containing wax antisolvent.
Claim 2
Dependent Claim
155 words
A process for treating a charge solution containing an organic oxygen-containing wax antisolvent and an aromatic hydrocarbon oil solvent in a charge ratio of organic oxygen-containing wax antisolvent to aromatic hydrocarbon oil solvent which comprises passing a charge solution containing an organic oxygen-containing wax antisolvent and an aromatic hydrocarbon oil solvent in a charge ratio of organic oxygen-containing wax antisolvent to aromatic hydrocarbon oil solvent into contact with, as non-porous pervaporation membrane, a high molecular weight ion exchange resin in membrane form having carbon atoms in the backbone bearing a pendant acid group which membrane has been contacted with as counter ion, a potassium salt or with a quaternary phosphonium salt containing hydrocarbyl groups; maintaining a pressure drop across said pervaporation membrane thereby forming (i) a retentate containing decreased content of oxygen-containing wax antisolvent; and recovering said retentate containing decreased content of oxygen-containing wax antisolvent and said permeate containing increased content of oxygen-containing wax antisolvent.
Claim 3
Dependent Claim
15 words
A process as claimed in claim 1 wherein said oxygen-containing wax antisolvent is a ketone.
Claim 4
Dependent Claim
16 words
A process as claimed in claim 1 wherein said oxygen-containing wax antisolvent is methyl ethyl ketone.
Claim 5
Dependent Claim
15 words
A process as claimed in claim 1 wherein said aromatic hydrocarbon oil solvent is toluene.
Claim 6
Dependent Claim
13 words
A process as claimed in claim 1 wherein said charge ratio is 0.7:1-1:1.
Claim 7
Dependent Claim
14 words
A process as claimed in claim 1 wherein said charge ratio is about 1:1.
Claim 8
Dependent Claim
17 words
A process as claimed in claim 1 wherein said charge solution contains methyl ethyl ketone and toluene.
Claim 9
Dependent Claim
23 words
A process as claimed in claim 1 wherein said charge solution contains methyl ethyl ketone and toluene in weight ratio of about 1:1.
Claim 10
Dependent Claim
17 words
A process as claimed in claim 1 wherein said quaternary phosphonium salt is a tetraphenyl phosphonium salt.
Claim 11
Dependent Claim
17 words
A process as claimed in claim 1 wherein said quaternary phosphonium salt is a tetrabutyl phosphonium salt.
Claim 12
Dependent Claim
143 words
A process for treating a charge solution containing methyl ethyl ketone and toluene in a charge ratio of methyl ethyl ketone to toluene which comprises passing a charge solution containing methyl ethyl ketone and toluene in charge ratio of methyl ethyl ketone to toluene into contact with, as non-porous pervaporation membrane, a perfluorinated hydrocarbon or a perfluorinated ether which contains no hydrogen groups except those on a pendant acid group which membrane has been contacted with, as counter ion, a potassium salt or a tetrabutyl phosphonium salt or tetraphenyl phosphonium salt; maintaining a pressure drop across said pervaporation membrane thereby forming (i) a retentate containing decreased content of methyl ethyl ketone and (ii) a permeate containing increased content of methyl ethyl ketone; and recovering said retentate containing decreased content of methyl ethyl ketone and said permeate containing increased content of methyl ethyl ketone.
Claim 13
Dependent Claim
143 words
A process for treating a charge solution containing methyl ethyl ketone and toluene in a charge ratio of methyl ethyl ketone to toluene which comprises passing a charge solution containing methyl ethyl ketone and toluene in charge ratio of methyl ethyl ketone to toluene into contact with, as non-porous pervaporation membrane, a perfluorinated hydrocarbon or a perfluorinated ether which contains no hydrogen groups except those on a pendant acid group which membrane has been contacted with, as counter ion, a potassium salt or a tetrabutyl phosphonium salt or tetraphenyl phosphonium salt; maintaining a pressure drop across said pervaporation membrane thereby forming (i) a retentate containing decreased content of methyl ethyl ketone and (ii) a permeate containing increased content of methyl ethyl ketone; and recovering said retentate containing decreased content of methyl ethyl ketone and said permeate containing increased content of methyl ethyl ketone.
Claim 14
Dependent Claim
24 words
A process as claimed in claim 1 wherein each of the hydrocarbyl groups in said quaternary phosphonium salt contains at least four carbon atoms.
References Cited (Backward Citations)
US4670146A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-02-05 | 1993-08-07 | 1994-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-05 | 1997-08-07 | 1998-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-05 | 2001-08-07 | 2002-02-06 | $7700.00 | Window Closed / Lapsed |