Control of hydrogen halide concentration in the isomerization of hydrocarbons

Claim 1

IN A PROCESS FOR THE ISOMERIZATION OF HYDROCARBONS WITH A METAL HALIDE CATALYST AND A HYDROGEN HALIDE, IN WHICH THE ISOMERIZATION REACTION EFFLUENT IS INTRODUCED TO A SURGE ZONE FROM WHICH NON-CONDENSABLE GASES, INCLUDING HYDROGEN HALIDE, ARE VENTED, MATERIAL FROM SAID SURGE ZONE IS INTRODUCED TO A STRIPING ZONE WHEREIN A GASEOUS MATERIAL RICH IN HYDROGEN HALIDE IS SEPARATED, SAID GASEOUS MATERIAL IS RECYCLED TO THE ISOMERIZATION REACTION AND FRESH HYDROGEN HALIDE IS INTRODUCED TO THE PROCESS AS MAKEUP, THE IMPROVEMENT WHICH COMPRISES MEASURING THE HYDROGEN HALIDE CONCENTRATION IN THE GASEOUS MATERIAL RECYCLED TO THE ISOMERIZATION ZONE, CONTROLLING THE CONCENTRATION OF HYDROGEN HALIDE IN THE REACTION SYSTEM AND REDUCING THE LOSS OF HYDROGEN HALIDE IN SAID SYSTEM BY VARYING THE RATE AT WHICH NON-CONDENSABLE GASES ARE VENTED FROM THE SURGE ZONE IN INVERSE PROPORTION TO AN IN RESPONSE TO VARIATIONS IN SAID HYDROGEN HALIDE CONCENTRATION, MEASURING THE PRESSURE IN THE SURGE ZONE, VARYING THE QUANTITY OF FRESH HYDROGEN HALIDE INTRODUCED TO THE PROCESS INVERSELY IN PROPORTION TO AND IN RESPONSE TO VARIATIONS IN SAID PRESSURE, MEASURING THE FLOW RATE OF HYDROCARBON REACTANT AND THE FLOW RATE AND HYDROGEN HALIDE CONCENTRATION OF GASEOUS RECYCLE MATERIAL TO THE ISOMERIZATION REACTION AND VARYING THE LATTER FLOW RATE IN INVERSE PROPORTION TO AND IN RESPONSE TO VARIATIONS IN THE HYDROGEN HALIDE CONCENTRATION IN SAID GASEOUS MATERIAL AND IN DIRECT PROPORTIN TO AND IN RESPONSE TO VARIATIONS IN THE RATE OF FEED OF HYDROCARBON REACTANT TO THE ISOMERIZATION REACTION.