Catalytic conversion process

Claim 1

A PROCESS FOR CATALYTICALLY DEHYDROGENATING A HYDROCARBON OF HIGHER SATURATION TO A HYDROCARBON OF LOWER SATURATION IN WHICH THE ACTIVITY OF THE CATALYST GRADUALLY DECREASES WITH CONCOMITANT CHANGE IN THE COMPOSITION OF THE EFFLUENT FROM THE REACTION ZONE, WHICH COMPRISES CONTACTING A DEHYDROGENATION CATALYST WITH A HYDROCARBON FEED STREAM AT LEAST AS SATURATED AS A MONO-OLEFIN IN A DEHYDROGENATION ZONE UNDER DEHYDROGENATION CONDITIONS SO AS TO CONVERT ONLY A PORTION OF THE FEED TO LESS SATURATED HYDROCARBON; INTRODUCING THE RESULTING MIXTURE OF HYDROCARBONS IN LIQUID PHASE INTO A LIQUID-LIQUID EXTRACTION ZONE AS A FEED AT SUCCESSIVELY VARYING LEVELS; PASSING A SELECTIVE SOLVENT FOR THE LESS SATURATED HYDROCARBON THROUGH SAID EXTRACTION ZONE COUNTERCURRENTLY TO THE FEED THERETO UNDER CONDITIONS WHICH EFFECT SELECTIVE SEPARATION OF SAID LESS SATURATED HYDROCARBON; WITHDRAWING RAFFINATE COMPRISING HYDROCARBON OF HIGHER SATURATION FROM ONE END OF SAID EXTRACTION ZONE AND LESS SATURATED HYDROCARBON-SOLVENT SOLUTION FROM THE OTHER; AND AUTOMATICALLY VARYING THE LEVEL OF INTRODUCTION OF THE FEED TO SAID EXTRACTION ZONE IN ACCORDANCE WITH A PREDETERMINED TIME CYCLE COORDINATED WITH VARIATIONS IN COMPOSITION OF SAID FEED SO AS TO MAINTAIN A RAFFINATE OF CONSTANT COMPOSITION.