Fractionation process

Claim 1

THE PROCESS FOR TREATING A PETROLEUM HYDROCARBON FEED MIXTURE BOILING OVER A RELATIVELY WIDE RANGE WITHIN THE GASOLINE BOILING RANGE AND COMPRISING STRAIGHT CHAIN AND NON-STRAIGHT CHAIN HYDROCARBONS, WHICH PROCESS COMPRISES: (1) CONTACTING SAID MIXTURE WITH A LEAN SOLID GRANDULAR ADSORBENT ESSENTIALLY COMPRISING A PARTIALLY DEHYDRATED ZEOLITIC METALLO ALUMINO SILICATE HAVING SUBSTANTIALLY UNIFORM PORES OF ABOUT 5 A. IN DIAMETER AND HAVING ADSORBED THEREON A DISPLACEMENT EXCHANGE FLUID OF RELATIVELY NARROW BOILING RANGE CONSISTING SUBSTANTIALLY ONLY OF STRAIGHT CHAIN HYDROCARBON COMPONENTS OF SAID FEED MIXTURE, WHEREBY THERE IS OBTAINED A RAFFINATE PRODUCT COMPRISING NON-ABSORBED NON-STRAIGHT CHAIN HYDROCARBON COMPONENTS OF THE FEED MIXTURE IN ADMIXTURE WITH DESORBED DISPLACEMENT EXCHANGE FLUID, AND A RICH ADSORBENT COMPRISING SAID GRANDULAR SILICATE HAVING ADSORBED THEREON STRAIGHT CHAIN COMPONENTS OF THE FEED MIXTURE, (2) SEPARATING SAID RAFFINATE PRODUCT FROM SAID RICH ADSORBENT, (3) CONTACTING SAID RICH ADSORBENT WITH SAID DISPLACEMENT EXCHANGE FLUID WHEREBY THE ADSORBENT IS RETURNED TO ITS LEAN STATE AND THERE IS OBTAINED AN EXTRACT PRODUCT COMPRISING DESORBED STRAIGHT CHAIN HYDROCARBON COMPONENTS OF THE FEED MIXTURE IN ADMIXTURE WITH SAID DISPLACEMENT EXCHANGE FLUID, (4) SEPARATING SAID EXTRACT PRODUCT FROM THE LEAN ADSORBENT, (5) RETURNING SAID EXTRACT LEAN ADSORBENT OBTAINED IN STEP (4) TO STEP (1), (6) TREATING THE RAFFINATE PRODUCT OBTAINED IN STEP (2) TO SEPARATE SAID NON-ADSORBED NON-STRAIGHT CHAIN HYDROCARBON COMPONENTS OF THE FEED MIXTURE FROM SAID DISPLACEMENT EXCHANGE FLUID, (7) TREATING THE EXTRACT PRODUCT OBTAINED IN STEP (4) TO SEPARATE THEREFROM A FRACTION OF RELATIVELY NARROW BOILING RANGE, AND (8) RETURNING AT LEAST A PART OF SAID FRACTION OF RELATIVELY NARROW BOILING RANGE TO STEP (3) AS SAID DISPLACEMENT EXCHANGE FLUID.