Patent ID: 7498472

Claim:
An ethylbenzene generation process using a dividing wall fractionation zone, said process comprising: contacting, in an alkylation zone, at least ethylene, 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 ethylbenzene and form an alkylation zone effluent comprising benzene and ethylbenzene; contacting, in a transalkylation zone, a polyethylbenzene recycle stream comprising at least polyethylbenzene 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 polyethylbenzene and benzene into ethylbenzene and form a transalkylation zone effluent comprising benzene and ethylbenzene; passing the alkylation zone effluent and the transalkylation zone effluent into a dividing wall fractionation column operated at fractionation conditions and dividing 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 alkylation zone effluent and the transalkylation zone effluent entering the column at intermediate points of the first fractionation zone and wherein the transalkylation zone effluent is introduced into the dividing wall fractionation column at an intermediate height of the dividing wall fractionation column which is in between the first end of the dividing wall fractionation column and the intermediate height at which the alkylation zone effluent is introduced; removing a stream comprising ethylbenzene from an intermediate point of the second fractionation zone of the dividing wall fractionation column; removing the first benzene recycle stream from a first end of the dividing wall fractionation column and wherein the dividing wall fractionation column is operated so that the first recycle benzene stream is at a pressure ranging from 103 to 241 kPa (15 to 35 psia) and a temperature ranging from about 88 to 104° C. (190 to 220° F.); removing a flux oil-rich stream from a second end of the dividing wall fractionation column; removing the second benzene recycle stream from an intermediate point of the second fractionation zone of the dividing wall fractionation column located between the first end of the dividing wall fractionation column and the ethylbenzene stream; and removing a polyethylbenzene-rich stream from an intermediate point of the second fractionation zone of the dividing wall fractionation column located between the second end of the dividing wall fractionation column and the ethylbenzene stream.