The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 1987
Filed:
Dec. 16, 1982
William C Rahlwes, Old Ocean, TX (US);
Phillips Petroleum Company, Bartlesville, OK (US);
Abstract
A hexanes stream, including normal hexane, isohexanes, methylcyclopentane and cyclohexane is isomerized by first fractionating the hexanes stream in a first fractionation step to produce a normal hexaneisohexanes rich overhead stream and a methylcyclopentane-cyclohexane rich bottoms stream, the bottom stream of the first fractionation step is isomerized to maximize the conversion of methylcyclopentane to cyclohexane, the overhead stream from the first fractionation step is fractionated in a second fractionation step to produce an isohexane rich overhead stream and a normal hexane rich bottoms stream, the effluent from the isomerization step is fractionated in at least one stage of a third fractionation step to produce a cyclohexane rich bottoms fraction and a methylcyclopentane-isohexane rich overhead stream and at least a part of the overhead stream from the third fractionation step is recycled to at least one of the isomerization steps and the first fractionation step. In one mode of operation, the overhead from the first stage of the third fractionation step is separated into an overhead stream rich in isohexanes which is combined with the overhead from the first fractionation step and passed to the second fractionation step and a bottoms stream rich is methylcyclopentane is thus recycled to the isomerization step or the first fractionation step. In a second mode of operation, the overhead from the first stage of the third fractionation step is recycled directly to the isomerization step and/or the first fractionation step.