Process for the separation of styrene from ethylbenzene
Abstract
Abstract STYRENE IS SEPARATED FROM ORGANIC MIXTURES COMPRISING STYRENE AND ETHYLBENZENE BY CONTACTING THE MIXTURE (FEED MIXTURE) AGAINST ONE SIDE OF A POLYURETHANE ELASTOMER MEMBRANE UNDER PERVAPORTAION PERMEATION CONDITIONS AND WITHDRAWING AT THE OTHER SIDE A VAPOROUS MIXTURE HAVING INCREASED STYRENE CONCENTRATION. THE POLYURETHANE ELASTOMER EMPLOYED CONTAINS POLYETHER OR POLYESTER GROUPINGS. EXAMPLES OF POLYURETHANE ELASTOMER POLYMERS ARE POLYMERS OF THE FORMULA -(OOC-NH-R2-NH-COO-(A)N-OOC-NH-R2)M-NH-COO-R3-OOC-NH- (R2-NH-COO-(A)N-OOC-NH-R2-NH-COO)M- WHEREIN R, R1, R2 AND R3 ARE DIVALENT ORGANIC RADICALS, R4 IS HYDROGEN OR AN ORGANIC RADICAL, A IS -R-OOC-R''-CO-, OR -CH2-CH(-R4)-O-CH2-CH(-R4)- N IS AN INTEGER IN THE RANGE OF 3-500 AND M IS NA INTEGER INDICATING THE DEGREE OF POLYMERIZATION.
Inventors
- 👤 W Strazik
- 👤 E Perry
Bibliographic Details
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