Process for production of cyclohexane

Claim 1

A PROCESS FOR PRODUCTION OF CYCLOHEXANE COMPRISING: FORMING A FEED MIXTURE OF A PETROLEUM DISTILLATE HAVING BOILING POINT RANGE BETWEEN ABOUT 160* AND ABOUT 225*F., SAID PETROLEUM DISTILLATE CONTAINING METHYLCYCLOPENTANE, CYCLOHEXANE, AND ASSOCIATED HYDROCARBONS WITH THE RATIO OF CYCLOHEXANE TO SAID ASSOCIATED HYDROCARBONS ABOVE ABOUT 0.1:1,AND A PORTION OF RECYCLED ISOMERIZA-TION REACTION PRODUCT CONTAINING ADDITIONAL CATALYTICALLYFORMED METHYLCYCLOPENTANE AND UNREACTED CYCLOHEXANE, SAID PORTION BEING OBTAIN FROM A LATER STAGE OF THE PROCESS AND ITS QUANTITY BEING REGULATED FOR MAINTAINING THE RATIO OF THE CYCLOHEXANE TO ASSOCIATED HYDROCARBONS IN SAID FEED MIXTURE AT A VALUE ABOVE ABOUT 0.1:1, STRIPPING A METHYLCYCLOPENTANE-RICH FRACTION HAVING BOILING POINT RANGE BETWEEN ABOUT 160* AND ABOUT 170*F. FROM SAID FEED MIXTURE, THEREBY LEAVING A LIQUID RESIDUE CONTAINING CYCLOHEXANE TOGETHER WITH ASSOCIATED HYDROCARBONS, STRIPPING A CYCLOHEXANE-ENRICHED DISTILLATE FROM SAID RESIDUE, ISOMERIZING THE MAJOR FRACTION OF CYCLOHEXANE IN SAID CYCLOHEXANE-ENRICHED DISTILLATE INTO ADDITIONAL METHYLCYCLOPENTANE BY CONTACTING SAID CYCLOHEXANE-ENRICHED DISTILLATE IN VAPOR PHASE WITH AN ISOMERIZATION CATALYST AT A TEMPERATURE OF 800-900*F. AND A PRESSURE OF 500-2000 P. S. I. G., RECYCLING A FRACTION OF THE ISOMERIZATION REACTION PRODUCT INTO ADMIXTURE WITH SAID PETROLEUM DISTILLATE FOR FORMING SAID FEED MIXTURE, RECOVERING ADDITIONAL CATALYTICALLY-FORMED METHYLCYCLOPENTANE FROM THE BALANCE OF THE ISOMERIZATION REACTION PRODUCT, CONDUCTING THE RECOVERED ADDITIONAL CATALYTICALLYFORMED METHYLCYCLOPENTANE, THE METHYLCYCLOPENTANE PREVIOUSLY STRIPPED FROM THE FEED MIXTURE, AND HYDROGEN INTO CONTACT WITH A HYDROFORMING CATALYST AT A TEMPERATURE MAINTAINED BETWEEN 840* AND 980*F. AND A PRESSURE BETWEEN 250 AND 500 P. S. I. G, THEREBY REFORMING METHYLCYCLOPENTANE INTO BENZENE AND HYDROGEN, CONVERTING SAID BENZENE INTO A CYCLOHEXANE-CONTAINING HYDROGENATION PRODUCT BY CATALYTIC HYDROGENATION WITH HYDROGEN AT A TEMPERATURE FROM 600* TO 800*F. AND A PRESSURE OF 500 TO 1000 P. S. I. G., AND FRACTIONALLY DISTILLING CYCLOHEXANE FROM THE RESULTING HYDROGENATION PRODUCT.