Patent ID: 8716545

Claim:
A method of separating toluene from multiple hydrocarbon streams, the method comprising: fractionating a first hydrocarbon stream in a first fractionation zone into a first fractionation overhead stream and a first fractionation bottom stream, wherein the first hydrocarbon stream comprises a benzene-depleted fractionation bottom stream from benzene fractionation, and wherein the first fractionation overhead stream comprises toluene; fractionating a second hydrocarbon stream different from the first hydrocarbon stream in a second fractionation zone into a second fractionation overhead stream and a second fractionation bottom stream, wherein the second fractionation zone is in liquid isolation from and in vapor communication with the first fractionation zone, wherein the second hydrocarbon stream comprises toluene and is substantially free of compounds having a higher vapor pressure than toluene, and wherein the second fractionation overhead stream comprises toluene; separately removing the first fractionation bottom stream from the first fractionation zone and the second fractionation bottom stream from the second fractionation zone; and combining the first fractionation overhead stream from the first fractionation zone and the second fractionation overhead stream from the second fractionation zone to produce a combined fractionation overhead stream comprising toluene.