US4012317A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for extracting urea from a solution with alkenylaromatic polymers with α-ketoalhydic groups
Assignee: Gambro Industries SAS
•
Filing: 1974-07-05
•
Granted: 1977-03-15
•
Expires: 1994-07-05
Abstract
Abstract An alkenylaromatic polymer is provided derived from 50 to 100 mol % of at least one monomer of the general formula: <IMAGE> (I) in which R' represents a hydrogen atom or a methyl radical and R'' represents a hydrogen atom or a methyl or ethyl radical, and 0 to 50 mol % of a non-aromatic ethylenically unsaturated monomer, optionally cross-linked by 0.1 to 30 mol %, relative to the monomer of formula (I), of a polyvinyl monomer, 0.01 to 1 alpha -ketoaldehyde group of the formula - CO - CHOII.
Inventors
- 👤 Emile Kuntz
- 👤 Jean Pierre Quentin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:42
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/22; A; A61; A61M; A61M1/00; A61M1/14; A61M1/16; A61M1/1694; A61M1/1696; C; C08; C08F; C08F8/00
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
124 words
Process for extracting urea from a solution containing urea which comprises contacting the solution with an alkenylaromatic polymer consisting essentially of: a. 50 to 100 % of recurring units of the formula: ##STR10##or recurring units of formula (VII) and recurring units selected from units of the formula: ##STR11##at least 0.01% of the recurring units being recurring units of formula (VII); and b. correspondingly 50-0% of recurring units of a non-aromatic ethylenically unsaturated monomer, in which R' represents a hydrogen atom or a methyl radical, R" represents a hydrogen atom or a methyl or ethyl radical and X represents a halogen atom; at least one of the aromatic rings in the recurring units of formulae (VII), (IV), (V), and (VI) optionally being substituted by halogen.
Claim 2
Dependent Claim
124 words
Process for extracting urea from a solution containing urea which comprises contacting the solution with an alkenylaromatic polymer consisting essentially of: a. 50 to 100 % of recurring units of the formula: ##STR10##or recurring units of formula (VII) and recurring units selected from units of the formula: ##STR11##at least 0.01% of the recurring units being recurring units of formula (VII); and b. correspondingly 50-0% of recurring units of a non-aromatic ethylenically unsaturated monomer, in which R' represents a hydrogen atom or a methyl radical, R" represents a hydrogen atom or a methyl or ethyl radical and X represents a halogen atom; at least one of the aromatic rings in the recurring units of formulae (VII), (IV), (V), and (VI) optionally being substituted by halogen.
Claim 3
Dependent Claim
19 words
Process according to claim 1, in which the urea is present as an acid, neutral or alkaline aqueous solution.
Claim 4
Dependent Claim
18 words
Process according to claim 2, in which the aqueous solution has a pH of between 7 and 12.
Claim 5
Dependent Claim
23 words
Process according to claim 3, in which the urea is contained in a solution resulting from the dialysis or ultrafiltration of human blood.
Claim 6
Dependent Claim
18 words
Process according to claim 1 in which the non-aromatic ethylenically unsaturated monomer is ethylene, propylene, butadiene or isoprene.
Claim 7
Dependent Claim
22 words
Process according to claim 1 in which the polymer is in the form of a powder, granules or hollow or porous fibres.
Claim 8
Dependent Claim
42 words
Process according to claim 1 in which the polymer is cross-linked by units of a polyvinyl monomer, said units being present in an amount from 0.1 to 30% based on the total number of units of formula (VII), )IV), (V) and (VI).
Claim 9
Dependent Claim
21 words
Process according to claim 7 in which the polyvinyl monomer is m-divinylbenzene, p-divinylbenzene, diisopropenylbenzene, a divinyltoluene, 1,3,5-trivinylbenzene, 1,2,4-trivinylbenzene or a divinylxylene.
Claim 10
Dependent Claim
21 words
Process according to claim 7 in which the polyvinyl monomer is divinylbenzene and R' and R" both represent a hydrogen atom.
Claim 11
Dependent Claim
12 words
Process according to claim 7 in which R" represents a hydrogen atom.
Claim 12
Dependent Claim
12 words
Process according to claim 1 in which R" represents a hydrogen atom.
Claim 13
Dependent Claim
59 words
Process according to claim 1 in which the alkenyl aromatic polymer is obtained by reacting dimethylsulphoxide with an alkenylaromatic polymer consisting essentially of: a. 50-100% of recurring units of the formula: ##STR12## or recurring units of formula (IV) and recurring units selected from units of the formula: ##STR13##b. correspondingly 50-0% of recurring units of a non-aromatic ethylenically unsaturated monomer.
References Cited (Backward Citations)
US2974178A
Cited
US3382034A
Cited
US3531463A
Cited
US3669878A
Cited
US3669880A
Cited
US3794584A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-14 | 1980-09-13 | 1981-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-14 | 1984-09-13 | 1985-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-14 | 1988-09-13 | 1989-03-15 | $7700.00 | Window Closed / Lapsed |