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US2640804A Expired / Lapsed US ⏱️ 0.0 years remaining

Purification of substituted aromatic compounds

Assignee: Phillips Petroleum Co
•
Filing: 1950-12-27
•
Granted: 1953-06-02
•
Expires: 1970-12-27
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Abstract

No abstract record available.

Inventors

  • 👤 William B Whitney

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 01:32
CPC Classifications
C; C07; C07C; C07C7/00; C07C7/148; C07C7/14808

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 91 words
A NON-CATALYTIC PROCESS FOR THE SEPARATION OF THE PARA-ISOMER FROM ISOMERIC MIXTURES OF DIALKYL BENZENOID HYDROCARBONS SELECTED FROM THE GROUP CONSISTTING OF XYLENES, DIETHYL BENZENES, CYMENES AND ETHYLTOLUENES WHICH COMPRISES REACTING SAID ISOMERIC MIXTURE WITH SULFUR MONOCHLORIDE AT A TEMPERATURE IN THE RANGE 20 TO 135* C. FOR A PERIOD OF TIME IN THE RANGE 20 TO 30 MINUTES AND AT SUBSTANTIALLY ATMOSPHERIC PRESSURE WHEREBY THE META- AND ORTHO-ISOMERS ARE SELECTIVELY SULFURIZED AND DISTILLING THE SUBSTANTIALLY UNREACTED PARA ISOMER FROM THE RESULTING HIGHER BOILING DISULFIDES OF THE META AND ORTHO ISOMERS.

References Cited (Backward Citations)

US2402635A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1956-06-01 1956-12-01 1957-06-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1960-06-01 1960-12-01 1961-06-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1964-06-01 1964-12-01 1965-06-02 $7700.00 Window Closed / Lapsed

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