Patent US3644201A successfully refreshed from Google Patents.
US3644201A
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Evaporation of water during urea adduct formation
Assignee: Shell USA Inc
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Filing: 1969-12-05
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Granted: 1972-02-22
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Expires: 1989-12-05
Abstract
Abstract Extractive crystallization separation process in which adduct formation and concentration of an aqueous solution of the adductforming agent are simultaneously performed in the same reaction zone.
Inventors
- 👤 Cornelis W C Van Paassen
- 👤 Hubrecht C A Van Meurs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:00
CPC Classifications
C; C07; C07B; C07B63/00; C07B63/02; B; B01; B01D; B01D57/00; B65; B65D; B65D63/00; C10; C10G; C10G73/00; C10G73/02; C10G73/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
22 words
The process of claim 1 wherein the liquid mixture to be separated comprises essentially straight-chain paraffinic hydrocarbons mixed with other hydrocarbon types.
Claim 2
Dependent Claim
28 words
The process of claim 1 wherein a diluent is introduced into the adducting zone, said diluent being selected from the group consisting of kerosene and light gas oils.
Claim 3
Dependent Claim
28 words
passing the separated adducts to a decomposition zone and contacting the same with water or steam under such conditions that decomposition occurs and two liquid phases are formed,
Claim 4
Dependent Claim
43 words
passing the two liquid phases from step (3) to a settling zone wherein the aqueous urea phase is recovered and recycled to the adducting zone without prior concentration and the paraffin phase is drawn off and recovered as the product of the process.
Claim 5
Dependent Claim
17 words
A process for the separation of a liquid mixture containing straight-chain and branched-chain paraffinic hydrocarbons which comprises:
Claim 6
Dependent Claim
41 words
The process of claim 4 wherein vapors resulting from the concentration of the aqueous urea solution in the adducting zone are compressed and at least part of the heat is withdrawn from the compressed vapors by means of direct heat exchange.
Claim 7
Dependent Claim
46 words
The process of claim 4 wherein the vapors resulting from the concentration of the aqueous urea solution in the adducting zone are condensed by means of direct or indirect heat exchange with a cooling agent and are used for the recovery of urea in aqueous solution.
Claim 8
Dependent Claim
22 words
The process of claim 4 wherein the hydrocarbon mixture and aqueous urea solution are mixed and subsequently atomized into the adducting zone.
Claim 9
Dependent Claim
29 words
The process of claim 5 wherein part of the compressed vapor from which the heat is to be withdrawn is brought in direct heat exchange with the separated adducts.
Claim 10
Dependent Claim
22 words
The process of claim 4 wherein the temperature in the adducting zone is maintained at between about 45* C. and 60* C.
References Cited (Backward Citations)
US2862868A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-21 | 1975-08-23 | 1976-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-21 | 1979-08-23 | 1980-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-21 | 1983-08-23 | 1984-02-22 | $7700.00 | Window Closed / Lapsed |