Process of recovering boron fluoride catalyst for the alkylation of phenols

Claim 1

IN THE ALKYLATION OF PHENOL WITH PROPYLENE POLYMER IN THE PRESENCE OF A CATALYST CONSISTING ESSENTIALLY OF BF3, THE METHOD OF RECOVERING BF3 FROM THE ALKYLATION REACTION MIXTURE WHICH COMPRISES ADDING 30% TO 200% BY WEIGHT BASED ON THE REACTION MIXTURE OF A LIQUID ENTRAINER, BOILING WITHIN THE RANGE 30 TO 200*C. SELECTED FROM THE GROUP CONSISTING OF PENTANE, HEXANE, HEPTANE, OCTANE, NONANE, CYCLOHEXANE, HYDROGENATED PROPYLENE POLYMER BOILING WITHIN THE RANGE OF 50* TO 130*C., INERT HYDROCARBONS ASSOCIATED WITH PROPYLENE POLYMER BOILING WITHIN THE RANGE 50* TO 130*C., BENZENE AND TOLUENE, EFFECTIVE TO RESULT IN BOILING OF THE REACTION MIXTURE PLUS ENTRAINER AT A TEMPERATURE WITHIN THE RANGE OF 50 TO 175*C., REFLUXING THE REACTION MIXTURE WITHIN SAID TEMPERATURE RANGE TO EVOLVE AS VAPOR A MIXTURE OF THE BF3 AND ENTRAINER WHILE SUBJECTING SAID VAPOR MIXTURE TO COOLING TO CONDENSE THE ENTRAINER WHILE LEAVING THE BF3 IN THE VAPOR STATE, RETURNING THE CONDENSED ENTRAINER TO THE REFLUXING MIXTURE, REMOVING THE BF3 AS VAPOR FROM THE CONDENSATION ZONE, CONTINUING THE REFLUXING UNTIL SUBSTANTIALLY ALL OF THE BF3 HAS REMOVED, AND ABSORBING THE BF3 VAPOR IN LIQUID PHENOL FOR REUSE IN THE PROCESS.