Hydrogen fluoride alkylation with effluent refrigeration

Claim 1

A PROCESS OF ALKYLATING ISOPARARRINIC HYDROCARBONS WITH OLEFINIC HYDROCARBONS EMPLOYING HYDROGEN FLUORIDE AS A CATALYST COMPRISING THE STEPS OF CONTACTING ISOPARAFFINIC HYDROCARBONS AND OLEFINIC HYDROCARBONS WITH LIQUID HYDROGEN FLUORIDE CATALYST IN A REACTION STEP, WITHDRAWING A MIXTURE OF HYDROCARBON WITH HYDROGEN FLUORIDE CATALYST AS EFFIUENT FROM SAID REACTION STEP, SEPERATING SAID EFFLUENT INTO A HYDROGEN FLUORIDE CONTAMINATED HYDROCARBON PHASE AND AN ACID PHASE IN A FIRST SEPARATING STEP, SAID REACTION STEP AND FIRST SEPERATING STEP MAINTAINED UNDER SUFFICIENT PRESSURE TO MAINTAIN THE HYDROCARBONS IN LIQUID FORM, REDUCING THE PRESSURE ON THE HYDROCARBONS FLUORIDE CONTAMINATED HYDROCARBON PHASE FROM SAID FIRST SEPARATING STEP IN AN EVAPORATIVE COOLING STEP, PASSING THE PRESSURE REDUCED HYDROGEN FLUORIDE CONTAMINATED HYDROCARBON PHASE TO A RELATIVELY LOW TEMPERATIVE AND LOW PRESSURE VAPOR WITHDRAWAL STEP, AND PASSING AT LEAST A SUFFICIENT QUANTITY OF SOME PORTION OF SAID HYDROCARBON PHASE AFTER PRESSURE REDUCTION THEREOF IN INDIRECT HEAT EXCHANGING RELATIONSHIP WITH SAID REACTION STEP TO MAINTAIN A TEMPERATURE LEVEL IN THE SAID VAPOR WITHDRAWAL STEP ADEQUATE TO THERE ESTABLISH A FLASH VAPORIZATION EQUILIBRIUM AT WHICH AT LEAST SUBSTANTIALLY ALL HYDROGEN FLUORIDE IS VAPORIZED FROM ALL LIQUID IN THE SAID VAPOR WITHDRAWAL STEP, AND PASSING HYDROGEN FLUORIDE-FREE LIQUID FROM THE VAPOR WITHDRAWAL STEP DIRECTLY TO AT LEAST ONE FRACTIONATION STEP FOR SEPERATION OF ISOPARAFFINIC HYDROCARBONS FROM SAID LIQUID.