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US4690688A Expired / Lapsed US ⏱️ 0.0 years remaining

Foam control

Assignee: Dow Silicones UK Ltd
•
Filing: 1986-02-24
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Granted: 1987-09-01
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Expires: 2006-02-24
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Abstract

Abstract The specification discloses a method of controlling foaming of liquid hydrocarbon fuels (e.g. diesel fuel and jet fuel) by inclusion therein of certain siloxane polyoxyalkylene copolymer as antifoam agents. The copolymers have an average molecular formula such that oxyalkylene groups of the copolymer provide from about 25% to about 65% by weight of the copolymer. Preferred copolymers are according to the general formula Me.sub.3 SiO(Me.sub.2 SiO).sub.x (MeR'SiO).sub.y SiMe.sub.3 in which each Me represents a methyl group, each R' represents a group according to the general formula Q(OA).sub.n OZ in which Q represents a divalent group attached to the silicon atom, each A represents an ethylene group, n has a value from 10 to 15, Z represents a hydrogen atom or a group OCR" in which R" represents a monovalent group and the ratio x:y lies in the range 1:1 to 11:1, more preferably in the range 3:1 to 7:1.

Inventors

  • 👤 Graham Adams
  • 👤 Martin A. Jones

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 13:36
CPC Classifications
C; C10; C10L; C10L1/00; C10L1/10; C10L1/14; C10L1/28; C10L1/285; B; B01; B01D; B01D19/00; B01D19/02; B01D19/04; B01D19/0404; B01D19/0409; F; F02; F02B; F02B3/00; F02B3/06

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 103 words
A method for controlling foaming of a liquid hydrocarbon fuel comprising the inclusion in the hydrcarbon fuel of an antifoam agent consisting essentially of a siloxane copolymer having the average general formula Me.sub.3 SiO(Me.sub.2 SiO).sub.x (MeR'SiO).sub.y SiMe.sub.3 wherein Me represents a methyl radical, R' represents the group Q(OCH 2 CH 2 ) n OZ in which Q represents an alkylene group having from 2 to 8 carbon atoms, n is 5 to 25 and Z represents hydrogen or a group OCR" in which R" denotes a monovalent hydrocarbon group, and wherein the ratio of x:y is in the range of 1:1 to 9:1.
Claim 2
Independent Claim 103 words
A method for controlling foaming of a liquid hydrocarbon fuel comprising the inclusion in the hydrcarbon fuel of an antifoam agent consisting essentially of a siloxane copolymer having the average general formula Me.sub.3 SiO(Me.sub.2 SiO).sub.x (MeR'SiO).sub.y SiMe.sub.3 wherein Me represents a methyl radical, R' represents the group Q(OCH 2 CH 2 ) n OZ in which Q represents an alkylene group having from 2 to 8 carbon atoms, n is 5 to 25 and Z represents hydrogen or a group OCR" in which R" denotes a monovalent hydrocarbon group, and wherein the ratio of x:y is in the range of 1:1 to 9:1.
Claim 3
Dependent Claim 19 words
A method according to claim 1 wherein the ratio of x:y is in the range from 3:1 to 7:1.
Claim 4
Dependent Claim 27 words
A method according to claim 1 wherein the copolymer is included to an extend of 5 to 50 parts by volume per million parts liquid hydrocarbon fuel.
Claim 5
Dependent Claim 17 words
A method according to claim 1 wherein the liquid hydrocarbon fuel is diesel fuel or jet fuel.
Claim 6
Dependent Claim 11 words
A hydrocarbon fuel treated by a method according to claim 1.
Claim 7
Dependent Claim 90 words
A liquid hydrocarbon fuel comprising an antifoam agent consisting essentially of a siloxane copolymer having the average general formula Me.sub.3 SiO(Me.sub.2 SiO).sub.x (MeR'SiO).sub.y SiMe.sub.3 wherein Me represents a methyl radical, R' represents the group Q(OCH 2 CH 2 ) n OZ in which Q represents an alkylene group having from 2 to 8 carbon atoms, n is 5 to 25 and Z represents hydrogen or a group OCR" in which R" denotes a monovalent hydrocarbon group, and wherein the ratio of x:y is in the range of 1:1 to 9:1.
Claim 8
Dependent Claim 90 words
A liquid hydrocarbon fuel comprising an antifoam agent consisting essentially of a siloxane copolymer having the average general formula Me.sub.3 SiO(Me.sub.2 SiO).sub.x (MeR'SiO).sub.y SiMe.sub.3 wherein Me represents a methyl radical, R' represents the group Q(OCH 2 CH 2 ) n OZ in which Q represents an alkylene group having from 2 to 8 carbon atoms, n is 5 to 25 and Z represents hydrogen or a group OCR" in which R" denotes a monovalent hydrocarbon group, and wherein the ratio of x:y is in the range of 1:1 to 9:1.
Claim 9
Dependent Claim 19 words
A fuel according to claim 6 wherein the ratio of x:y is in the range from 3:1 to 7:1.
Claim 10
Dependent Claim 38 words
A fuel according to claim 6 wherein the liquid hydrocarbon fuel is diesel fuel or jet fuel and the copolymer is present to an extent of 5 to 50 parts by volume per million parts liquid hydrocarbon fuel.

References Cited (Backward Citations)

US2917480A Cited
US2862885A Cited
US2992083A Cited
US3057901A Cited
US3233986A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-08-31 1991-03-02 1991-09-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-08-31 1995-03-02 1995-09-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-08-31 1999-03-02 1999-09-01 $7700.00 Window Closed / Lapsed

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