US4838900A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyimide gas separation membranes
Assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
•
Filing: 1988-04-13
•
Granted: 1989-06-13
•
Expires: 2008-04-13
Abstract
Abstract Aromatic polyimide gas separation membranes of the formula: ##STR1## or mixtures thereof, --R'--is ##STR2## linear alkylene groups of the formula (CH 2 ) 1-3 or mixtures thereof, where --R" is ##STR3## are independently primary or secondary alkyl groups having 1 to 6 carbon atoms preferably methyl, ethyl, or isopropyl --Z and --Z 1 are independently hydrogen or halogens such as iodine, bromine or chlorine preferably chlorine, and where n=0-4.
Inventors
- 👤 Richard A. Hayes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:06
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/58; B01D71/62; B01D71/64; C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1042; B01D53/00; B01D53/22; B01D53/228; C08G73/1057; C08G73/1064; C08G73/1067; C08G73/1071
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
85 words
A process of separating two or more gases comprising the steps of bringing two or more gases into contact with one side of a permselective membrane which is formed of an aromatic polyimide of the formula: ##STR6## or mixtures thereof, --R'-- is ##STR7## linear alkylene groups of the formula (CH 2 ) 1-3 or mixtures thereof, where --R"-- is ##STR8## are independently primary or secondary alkyl groups having 1 to 6 carbon atoms; --Z and --Z 1 are independently hydrogen or halogen, and where n=0-4.
Claim 2
Dependent Claim
85 words
A process of separating two or more gases comprising the steps of bringing two or more gases into contact with one side of a permselective membrane which is formed of an aromatic polyimide of the formula: ##STR6## or mixtures thereof, --R'-- is ##STR7## linear alkylene groups of the formula (CH 2 ) 1-3 or mixtures thereof, where --R"-- is ##STR8## are independently primary or secondary alkyl groups having 1 to 6 carbon atoms; --Z and --Z 1 are independently hydrogen or halogen, and where n=0-4.
Claim 3
Dependent Claim
14 words
The process of claim 1 where --Z and --Z 1 are hydrogen or chlorine.
Claim 4
Dependent Claim
7 words
The process of claim 1 where ##STR9##
Claim 5
Dependent Claim
7 words
The process of claim 1 where ##STR10##
Claim 6
Dependent Claim
7 words
The process of claim 1 where ##STR11##
Claim 7
Dependent Claim
7 words
The process of claim 5 where ##STR12##
Claim 8
Dependent Claim
7 words
The process of claim 5 where ##STR13##
Claim 9
Dependent Claim
72 words
An aromatic polyimide gas separation membrane wherein the aromatic polyimide has the formula: ##STR14## or mixtures thereof, --R'-- is ##STR15## linear alkylene groups of the formula (CH 2 ) 1-3 or mixtures thereof, where --R"-- is ##STR16## --X, --X 1 , --X 2 , and --X 3 are independently primary or secondary alkyl groups having 1 to 6 carbon atoms; --Z and --Z 1 are independently hydrogen or halogen, and where n=0-4.
Claim 10
Dependent Claim
72 words
An aromatic polyimide gas separation membrane wherein the aromatic polyimide has the formula: ##STR14## or mixtures thereof, --R'-- is ##STR15## linear alkylene groups of the formula (CH 2 ) 1-3 or mixtures thereof, where --R"-- is ##STR16## --X, --X 1 , --X 2 , and --X 3 are independently primary or secondary alkyl groups having 1 to 6 carbon atoms; --Z and --Z 1 are independently hydrogen or halogen, and where n=0-4.
Claim 11
Dependent Claim
16 words
The gas separation membrane of claim 8 where --Z and --Z 1 are hydrogen or chlorine.
Claim 12
Dependent Claim
9 words
The gas separation membrane of claim 8 where ##STR17##
Claim 13
Dependent Claim
9 words
The gas separation membrane of claim 8 where ##STR18##
Claim 14
Dependent Claim
9 words
The gas separation membrane of claim 8 where ##STR19##
Claim 15
Dependent Claim
9 words
The gas separation membrane of claim 12 where ##STR20##
Claim 16
Dependent Claim
9 words
The gas separation membrane of claim 12 where ##STR21##
References Cited (Backward Citations)
US30351A
Cited
US3423491A
Cited
FR2050251A1
Cited
US3957651A
Cited
US3822202A
Cited
USRE30351E
Cited
US3816303A
Cited
US4113628A
Cited
US4156597A
Cited
US4240914A
Cited
US4378324A
Cited
US4358378A
Cited
US4370290A
Cited
US4378400A
Cited
US4460526A
Cited
US4474662A
Cited
US4512893A
Cited
GB2102333A
Cited
US4440643A
Cited
US4528004A
Cited
GB2104411A
Cited
US4474858A
Cited
US4532041A
Cited
US4629777A
Cited
US4629685A
Cited
US4690873A
Cited
US4705540A
Cited
US4746474A
Cited
US4717393A
Cited
US4717394A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-12 | 1992-12-12 | 1993-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-12 | 1996-12-12 | 1997-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-12 | 2000-12-12 | 2001-06-13 | $7700.00 | Window Closed / Lapsed |