Patent USRE31048E successfully refreshed from Google Patents.
Patent US3898294A successfully refreshed from Google Patents.
US3898294A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chloroprene process improvement
Assignee: Petro Tex Chemical Corp
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Filing: 1972-11-06
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Granted: 1975-08-05
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Expires: 1992-11-06
Abstract
Abstract Reduced fouling in the apparatus for stripping residual organics from the byproduct aqueous salt solution produced in the dehydrohalogenation of halogenated hydrocarbons especially those containing 4 carbon atoms and reduced fouling in the apparatus used in purifying the dehydrohalogenated products produced are accomplished by the addition of formaldehyde or paraformaldehyde to the aqueous salt solution.
Inventors
- 👤 Stone D Cooley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:52
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/25
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
156 words
IN A CONTINUOUS PROCESS FOR DEHYDROHALOGENATING AN ORGANIC HALOGENATED COMPOUND BY REACTING SAID ORGANIC HALOGENATED COMPOUND SELECTED FROM THE GROUP CONSISTING OF 3,4-DICHLOROBUTENE-1,2,3,4-TRICHLOROBUTENE-1 AND 1,2,3,4-TETRACHLOROBUTANE WITH AN AQUEOUS SOLUTION OF A HYDROXIDE SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDES AND ALKALINE EARTH METAL HYDROXIDES, TO PRODUCE THE CORRESPONDING DEHYDROHALOGENATED ORGANIC COMPOUND IN AN AQUEOUS SALT SOLUTION, SAID PROCESS COMPRISING THE STEPS OF A. CONTINUOUSLY FEEDING SAID ORGANIC HALOGENATED COMPOUND ANDSAID AQUEOUS SOLUTION OF HYDROXIDE TO A REACTOR TO FORM A REACTION MIXTURE, B. HEATING SAID REACTION MIXTURE TO A TEMPERATURE BETWEEN 70* AND 130*C THEREBY EVOLVING A VAPOROUS COMPOSITION FROM SAID REACTION MIXTURE, SAID VAPOROUS COMPOSITION COMPRISING PREDOMINANTLY THE DEHYDROHALOGENATED ORGANIC COMPOUND AND UNREACTED ORGANIC HALOGENATED COMPOUND, C. WITHDRAWING SAID VAPOROUS COMPOSITION FROM SAID REACTOR AND RECOVERING SAID DEHYDROHALOGENATED ORGANIC COMPOUND THEREFROM, D. CONTINUOUSLY WITHDRAWING APORTION OF SAID REACTION MIXTURE FROM SAID REACTOR TO MAINTAIN A CONSTANT AMOUNT OF REACTION MIXTURE IN SAID REACTOR,
Claim 2
Dependent Claim
156 words
IN A CONTINUOUS PROCESS FOR DEHYDROHALOGENATING AN ORGANIC HALOGENATED COMPOUND BY REACTING SAID ORGANIC HALOGENATED COMPOUND SELECTED FROM THE GROUP CONSISTING OF 3,4-DICHLOROBUTENE-1,2,3,4-TRICHLOROBUTENE-1 AND 1,2,3,4-TETRACHLOROBUTANE WITH AN AQUEOUS SOLUTION OF A HYDROXIDE SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDES AND ALKALINE EARTH METAL HYDROXIDES, TO PRODUCE THE CORRESPONDING DEHYDROHALOGENATED ORGANIC COMPOUND IN AN AQUEOUS SALT SOLUTION, SAID PROCESS COMPRISING THE STEPS OF A. CONTINUOUSLY FEEDING SAID ORGANIC HALOGENATED COMPOUND ANDSAID AQUEOUS SOLUTION OF HYDROXIDE TO A REACTOR TO FORM A REACTION MIXTURE, B. HEATING SAID REACTION MIXTURE TO A TEMPERATURE BETWEEN 70* AND 130*C THEREBY EVOLVING A VAPOROUS COMPOSITION FROM SAID REACTION MIXTURE, SAID VAPOROUS COMPOSITION COMPRISING PREDOMINANTLY THE DEHYDROHALOGENATED ORGANIC COMPOUND AND UNREACTED ORGANIC HALOGENATED COMPOUND, C. WITHDRAWING SAID VAPOROUS COMPOSITION FROM SAID REACTOR AND RECOVERING SAID DEHYDROHALOGENATED ORGANIC COMPOUND THEREFROM, D. CONTINUOUSLY WITHDRAWING APORTION OF SAID REACTION MIXTURE FROM SAID REACTOR TO MAINTAIN A CONSTANT AMOUNT OF REACTION MIXTURE IN SAID REACTOR,
Claim 3
Dependent Claim
33 words
A process as claimed in claim 1 wherein the formaldehyde is present in an amount of from 0.5 to 50 parts by weight per 1000 parts by weight of dehydrohalogenated compounds being produced.
Claim 4
Dependent Claim
19 words
A process as claimed in claim 1 wherein formaldehyde is added to the withdrawn vaporous composition from said reactor.
Claim 5
Dependent Claim
76 words
A process as claimed in claim 1 wherein said dehydrohalogenated organic compound which is recovered from the vaporous composition from said reactor is further contacted with an aqueous solution of said hydroxide in a scrubber, removing a vaporous stream of dehydrohalogenated organic compound, removing the aqueous solution from said contacting step containing small amounts of acetaldehyde and other impurities removed from the vaporous dehydrohalogenated organic compound, feeding said aqueous solution from the scrubber to said reactor.
Claim 6
Dependent Claim
34 words
A process as claimed in claim 4 wherein the formaldehyde is present in an amount of from 0.5 to 50 parts by weight per 1000 parts by weight of dehydrohalogenated organic compound being treated.
Claim 7
Dependent Claim
14 words
A process as claimed in claim 1 wherein said halogenated organic compound is 3,4-dichlorobutene-1.
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) | 1978-08-04 | 1979-02-03 | 1979-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-04 | 1983-02-03 | 1983-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-04 | 1987-02-03 | 1987-08-05 | $7700.00 | Window Closed / Lapsed |