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US4028226A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of rerefining oil with recovery of useful organic additives

Assignee: Lubrizol Corp
•
Filing: 1975-11-12
•
Granted: 1977-06-07
•
Expires: 1995-11-12
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Abstract

Abstract Used oil is rerefined by diluting it with a water-soluble polar diluent and removing insoluble impurities from the resulting solution, adding water to produce a two-phase system, separating the organic phase and removing the polar diluent therefrom. By this method, it is possible to recover oil which still contains viscosity modifying additives and the like. If desired, the rerefined oil can be subjected to further treatment such as hydrogenation.

Inventors

  • 👤 John Wesley Forsberg

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 06:30
CPC Classifications
C; C10; C10M; C10M175/00; C10M175/005

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 110 words
A method of recovering oil of lubricating viscosity from used oil of lubricating viscosity which comprises the steps of: A. diluting said used oil with a water-soluble polar diluent in which said used oil is substantially soluble, said diluent comprising a lower alkanol or lower alkanone, and removing impurities insoluble in the soluble in the solution of said oil in said polar diluent from said solution; B. removing a major amount of said polar diluent for the solution of step A by addition of water having a pH of about 6-8 and removal of the resulting aqueous phase; and C. removing the balance of said polar diluent from said oil.
Claim 2
Independent Claim 110 words
A method of recovering oil of lubricating viscosity from used oil of lubricating viscosity which comprises the steps of: A. diluting said used oil with a water-soluble polar diluent in which said used oil is substantially soluble, said diluent comprising a lower alkanol or lower alkanone, and removing impurities insoluble in the soluble in the solution of said oil in said polar diluent from said solution; B. removing a major amount of said polar diluent for the solution of step A by addition of water having a pH of about 6-8 and removal of the resulting aqueous phase; and C. removing the balance of said polar diluent from said oil.
Claim 3
Dependent Claim 16 words
A method according to claim 1 wherein the water used in step B is substantially neutral.
Claim 4
Dependent Claim 18 words
A method according to claim 2 wherein insoluble impurities are removed in step A by centrifugation or filtration.
Claim 5
Dependent Claim 22 words
A method according to claim 3 wherein the polar diluent in step A is 1-butanol or a mixture of methanol and 1-butanol.
Claim 6
Dependent Claim 15 words
A method according to claim 3 wherein the polar diluent in step A is 1-butanol.
Claim 7
Dependent Claim 23 words
A method according to claim 2 wherein step C is effected by stripping volatile materials from the product of step B under vacuum.
Claim 8
Dependent Claim 22 words
A method according to claim 6 wherein the polar diluent in step A is 1-butanol or a mixture of methanol and 1-butanol.
Claim 9
Dependent Claim 15 words
A method according to claim 6 wherein the polar diluent in step A is 1-butanol.
Claim 10
Dependent Claim 18 words
A method according to claim 6 wherein the material removed by stripping includes a fraction recoverable as fuel.

References Cited (Backward Citations)

US1584588A Cited
US1766768A Cited
US1882002A Cited
US1990359A Cited
US2294461A Cited
US2376418A Cited
US2568583A Cited
US3763036A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-06-06 1980-12-06 1981-06-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-06-06 1984-12-06 1985-06-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-06-06 1988-12-06 1989-06-07 $7700.00 Window Closed / Lapsed

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