Extractive condensation process using a multistage column

Claim 1

A PROCESS FOR EFFECTING THE LIQUID PHASE ALKYLATION OF AN ISOPARAFFNIC MATERIAL WITH AN OLEFIN IN THE PRESENCE OF AN ACID ALKYLATION CATALYST WHICH COMPRISES: (1) INTRODUCING SAID ISOPARAFFINIC MATERIAL INTO A LOWER ONE OF A PLURALITY OF VERTICALLY SPACED CONTACTING ZONES, EACH ZONE BEING IN RESTRICTED FLUID COMMUNICATION WITH THE NEXT SUBJACENT ZONE THROUGH A MULTIPLICITY OF HORIZONTALLY SPACED APERTURES; (2) FLOWING SAID ISOPARAFFNIC MATERIAL UPWARDLY FROM EACH ZONE INTO THE NEXT SUPERJACENT ZONE AS A CONFINED STREAM WHILE MAINTAINING THE ISOPARAFFNIC MATERIAL WITHIN EACH ZONE IN A CONTINUOUS LIQUID PHASE; (3) INTRODUCING SAID ACID CATALYST INTO AN UPPER ONE OF SAID CONTACTING ZONES AND PASSING THE CATALYST DOWNWARDLY THROUGH SAID HORIZONTALLY SPACED APERTURES AND THROUGH SUCCESSIVE SUBJACENT CONTACTING ZONES AS A DISPERSED PHASE IN COUNTERCURRENT FLOW TO SAID CONTINUOUS PHASE; (4) INJECTING FEED STOCK CONTAINING SAID OLEFIN DIRECTLY INTO A SELECTED ONE OF THE RESULTING PLURALITY OF VERTICALLY SPACED UPFLOWING CONFINED STREAMS OF ISO-