Process for producing benzene and cyclohexane

Claim 1

A METHOD FOR PRODUCING CYCLOHEXANE FROM A FIRST FEED STREAM CONTAINING METHYLCYCLOPENTANE, BENZENE, AND HEXANES INCLUDING CYCLOHEXANE AND A SECOND FEED STREAM CONTAINING A MAJOR AMOUNT OF METHYLCYCLOPENTANE AND MINOR AMOUNTS OF HEXANES COMPRISING THE STEPS OF: (A) SEPARATING FROM THESE FEED STREAMS IN A FIRST FRACTIONATION STEP A FIRST FRACTION CONTAINING THE MAJOR PORTIONS OF THE METHYLCYCLOPENTANE, BENZENE AND CYCLOHEXANE; (B) SEPARATING THIS FIRST FRACTION IN A SECOND FRACTIONATION STEP INTO A SECOND FRACTION CONTAINING THE MAJOR PORTION OF THE CYCLOHEXANE AND A MINOR PORTION OF THE METHYLCYCLOPENTANE OF SAID FIRST FRACTION AND A THIRD FRACTION CONTAINING THE MAJOR PORTIONS OF THE METHYLCYCLOPENTANE AND THE BENZENE OF THE FIRST FRACTION; (C) CATALYTICALLY REFORMING SAID SECOND FRACTION IN THE PRESENCE OF ADDED GAS TO FORM BENZENE; (D) SEPARATING THE EFFLUENT OF THE REFORMING STEP INTO A HYDROGEN GAS PHASE AND A REFORMATE PHASE RICH IN BENZENE, THIS GAS PHASE COMPRISING SAID ADDED HYDROGEN GAS; (E) FROM THE REFORMATE PHASE SEPARATING BENZENE AS A FIRST PRODUCT OF THE OPERATION AND SEPARATING AN ADDITIONAL FRACTION RICH IN METHYLCYCLOPENTANE, SAID ADDITIONAL FRACTION COMPRISING THE AFORESAID SECOND FEED STREAM; (F) HYDROGENATING SAID THIRD FRACTION THEREBY CONVERTING BENZENE THEREIN INTO CYCLOHEXANE; (G) ISOMERIZING THE EFFLUENT OF THIS LATTER HYDROGENATING STEP THEREBY CONVERTING METHYLCYCLOPENTANE INTO CYCLOHEXANE; (H) FROM THE EFFLUENT OF THIS ISOMERIZING STEP SEPARATING A FRACTION RICH IN CYCLOHEXANE AS A SECOND PRODUCT OF THE OPERATION; (I) FOR A SUBSTANTIAL PERIOD OF TIME, INCREASING THE YIELD OF CYCLOHEXANE BY OPERATING SAID SECOND FRACTIONATION STEP SO AS TO DECREASE THE CONCENTRATION OF METHYLCYCLOPENTANE IN SAID SECOND FRACTION; AND (J) FOR ANOTHER SUBSTANTIAL PERIOD OF TIME, INCREASING THE YIELD OF BENZENE BY OPERATING SAID SECOND FRACTIONATION STEP SO AS TO INCREASE THE CONCENTRATION OF METHYLCYCLOPENTANE IN SAID SECOND FRACTION.

Claim 2

A METHOD FOR PRODUCING CYCLOHEXANE FROM A FIRST FEED STREAM CONTAINING METHYLCYCLOPENTANE, BENZENE, AND HEXANES INCLUDING CYCLOHEXANE AND A SECOND FEED STREAM CONTAINING A MAJOR AMOUNT OF METHYLCYCLOPENTANE AND MINOR AMOUNTS OF HEXANES COMPRISING THE STEPS OF: (A) SEPARATING FROM THESE FEED STREAMS IN A FIRST FRACTIONATION STEP A FIRST FRACTION CONTAINING THE MAJOR PORTIONS OF THE METHYLCYCLOPENTANE, BENZENE AND CYCLOHEXANE; (B) SEPARATING THIS FIRST FRACTION IN A SECOND FRACTIONATION STEP INTO A SECOND FRACTION CONTAINING THE MAJOR PORTION OF THE CYCLOHEXANE AND A MINOR PORTION OF THE METHYLCYCLOPENTANE OF SAID FIRST FRACTION AND A THIRD FRACTION CONTAINING THE MAJOR PORTIONS OF THE METHYLCYCLOPENTANE AND THE BENZENE OF THE FIRST FRACTION; (C) CATALYTICALLY REFORMING SAID SECOND FRACTION IN THE PRESENCE OF ADDED GAS TO FORM BENZENE; (D) SEPARATING THE EFFLUENT OF THE REFORMING STEP INTO A HYDROGEN GAS PHASE AND A REFORMATE PHASE RICH IN BENZENE, THIS GAS PHASE COMPRISING SAID ADDED HYDROGEN GAS; (E) FROM THE REFORMATE PHASE SEPARATING BENZENE AS A FIRST PRODUCT OF THE OPERATION AND SEPARATING AN ADDITIONAL FRACTION RICH IN METHYLCYCLOPENTANE, SAID ADDITIONAL FRACTION COMPRISING THE AFORESAID SECOND FEED STREAM; (F) HYDROGENATING SAID THIRD FRACTION THEREBY CONVERTING BENZENE THEREIN INTO CYCLOHEXANE; (G) ISOMERIZING THE EFFLUENT OF THIS LATTER HYDROGENATING STEP THEREBY CONVERTING METHYLCYCLOPENTANE INTO CYCLOHEXANE; (H) FROM THE EFFLUENT OF THIS ISOMERIZING STEP SEPARATING A FRACTION RICH IN CYCLOHEXANE AS A SECOND PRODUCT OF THE OPERATION; (I) FOR A SUBSTANTIAL PERIOD OF TIME, INCREASING THE YIELD OF CYCLOHEXANE BY OPERATING SAID SECOND FRACTIONATION STEP SO AS TO DECREASE THE CONCENTRATION OF METHYLCYCLOPENTANE IN SAID SECOND FRACTION; AND (J) FOR ANOTHER SUBSTANTIAL PERIOD OF TIME, INCREASING THE YIELD OF BENZENE BY OPERATING SAID SECOND FRACTIONATION STEP SO AS TO INCREASE THE CONCENTRATION OF METHYLCYCLOPENTANE IN SAID SECOND FRACTION.