Patent ID: 7525005
Filing Date: 2009-04-28
Classification: C07C

Abstract:
1. A cumene generation process using a dividing wall fractionation zone, said process comprising: contacting, in an alkylation zone, at least propylene and benzene and a first benzene recycle stream comprising at least benzene with an alkylation catalyst under alkylation conditions to convert at least a portion of the ethylene and benzene into cumene and form an alkylation zone effluent comprising at least benzene and cumene; contacting, in a transalkylation zone, a polyisopropylbenzene recycle stream comprising at least polyisopropylbenzene and a second benzene recycle stream comprising at least benzene with a transalkylation catalyst under transalkylation conditions to convert at least a portion of the polyisopropylbenzene and benzene into cumene and form a transalkylation zone effluent comprising at least benzene and cumene; passing the alkylation zone effluent and the transalkylation zone effluent into a benzene fractionation column operated at fractionation conditions to recover net benzene overhead thus forming the first benzene recycle stream, to separate benzene into a side draw to generate the second benzene recycle stream and to recover a net benzene column bottoms stream comprising cumene, polyisopropylbenzene and heavy aromatics wherein the transalkylation zone effluent is introduced into the benzene column at an intermediate height of the benzene column which is between an intermediate height at which the alkylation zone effluent is introduced and the first end of the benzene column; passing the net benzene column bottoms stream into a dividing wall fractionation column operated at fractionation conditions and divided into at least a first and a second parallel fractionation zone by a dividing wall, with the first and the second fractionation zones each having an upper and a lower end located within the fractionation column, with the first and second fractionation zones being in open communication at their upper ends with an undivided upper section of the fractionation column and in open communication at their lower ends with an undivided lower section of the fractionation column, and with the benzene column bottoms stream entering the column at an intermediate point of the first fractionation zone; removing a stream comprising polyisopropylbenzene from an intermediate point of the second fractionation zone of the dividing wall fractionation column to generate the polyisopropylbenzene recycle stream; removing a cumene-rich stream from the first end of the dividing wall fractionation column; and removing a heavy aromatics-rich stream from a second end of the dividing wall fractionation column.