Purification of alkylate using aromatics or cycloparaffins

Claim 1

A UNITARY PROCESS COMPRISING FORMING AN ISOPARAFFIN-OLEFIN ALKYLATE PRODUCT USING AN HF ACID CATALYST, SEPARATING SAID ALKYLATE PRODUCT INTO AN ACID CATALYST LAYER AND A HYDROCARBON ALKYLATE LAYER CONTAMINATED WITH THERMALLY DECOMPOSABLE HYDROCARBON-ACID COMPOUNDS, SEPARATING OUT SAID CONTAMINATED HYDROCARBON LAYER, FRACTIONATING A NAPHTHA FEED MATERIAL, SEPARATING FROM SAID NAPHTHA FEED FRACTIONATION OPERATION AN INTERMEDIATE HYDROCARBON FRACTION BOILING IN THE RANGE OF FROM ABOUT 150 TO ABOUT 400*F., REFORMING SAID INTERMEDIATE FRACTION TO FORM A REFORMATE CONTAINING SUBSTANTIAL AMOUNTS OF AROMATIC HYDROCARBON, SEPARATING SAID AROMATIC HYDROCARBON FROM SAID REFORMATE, ADDING SAID SEPARATED AROMATIC HYDROCARBON AND NO ADDITIONAL CATLYST TO SAID SEPARATED CONTAMINATED HYDROCARBON LAYER IN AMOUNTS EFFECTIVE TO FORM AT LEAST SOME ADDITIONAL ALKYLATE NOTWITHSTANDING NO ADDITIONAL CATALYST IS USED, AND SUBJECTING THE MIXTURE OF AROMATIC HYDROCARBON AND SAID CONTAMINATED HYDROCARBON LAYER TO THERMAL CONDITIONS SUFFICIENTLY ELEVATED TO CAUSE BOTH FREEING OF ACID CATALYST FROM SAID HYDROCARBON-ACID COMPOUNDS FOR SEPARATION AND REUSE IN FORMING MORE OF SAID ALKYLATE PRODUCT AND FORMING ADDITIONAL LAKYLATE, THEREBY PURIFYING SAID CONTAMINATED HYDROCARBON LAYER.