US3629076A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Distillation of styrene containing a polymerization inhibitor and contacting the bottoms stream with an alcohol
Assignee: Universal Oil Products Co
•
Filing: 1970-09-08
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Granted: 1971-12-21
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Expires: 1990-09-08
Abstract
Abstract Recovering polymerization inhibitor, including sulfur, cut-back oil, when employed, and undistilled styrene from the bottoms product of a styrene distillation column by treating the bottoms product with alcohol to precipitate polystyrene and part of the sulfur. The remaining liquid, including the remaining portion of the sulfur, is recycled back in the system. This improved method reduces the sulfur disposal problem and also recovers valuable materials.
Inventors
- 👤 Edwin K Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:27
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/04; C07C7/20; Y; Y10; Y10S; Y10S585/00; Y10S585/8995; Y10S585/901; Y10S585/949; Y10S585/95
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
27 words
The method of claim 1 in which the remaining liquid is fractionated to recover the alcohol for reuse in the process and to separate alcohol-free remaining liquid.
Claim 2
Dependent Claim
22 words
The method of claim 2 in which the alcohol-free remaining liquid is recycled at least in part to the first mentioned distillation.
Claim 3
Dependent Claim
25 words
The method of claim 2 in which the alcohol-free remaining liquid is recycled at least in part to an earlier column in the distillation train.
Claim 4
Dependent Claim
23 words
The method of claim 1 in which Tertiarybutylcatechol is supplied to the first mentioned distillation and is recovered in said remaining light liquid.
Claim 5
Dependent Claim
24 words
The method of claim 1 in which cut-back oil is supplied to the first mentioned distillation and is recovered in said remaining light liquid.
Claim 6
Dependent Claim
11 words
The method of claim 1 in which said alcohol is menthanol.
Claim 7
Dependent Claim
19 words
The method of claim 1 in which the precipitated solid is separated from the remaining light liquid by filtering.
Claim 8
Dependent Claim
18 words
The method of claim 1 in which the precipitated material is separated as a bottom layer by settling.
Claim 9
Dependent Claim
19 words
The method of claim 1 in which sulfur is extracted from said precipitated materials by treating with ammonium sulfide.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |