Yamada, Bunshi; Kimura, Michio; Noguchi, Yoshio;

Process for separating dichlorocumene isomer

A specific isomer of dichlorocumene is separated from a mixture containing dichlorocumene isomers by adsorptive separation, wherein the zeolite having at least 2 of silica/alumina molar ratio and 0.6 to 1.0 nm of pore size is used as the adsorbent and halogenated benzene or halogenated alkyl benzene is used as desorbent.

What we claim is:

1. A process for separate 3,5-dichlorocumene isomer from a mixture consisting substantially of dichlorocumene isomers by absorptive separation, which comprises contacting the isomer mixture with a zeolite adsorbent having a silica/alumina molar ratio of at least 2 and a pore size of 0.6 to 1.0 nm, and eluting the adsorbed isomer by contacting the zeolite adsorbent with a desorbent selected from the group consisting of halogenated benzene and halogenated alkyl benzene.

2. A process according to claim 1, wherein said zeolite is selected from the group consisting of type X, type Y, type L and type beta zeolite.

3. A process according to claim 1, wherein said zeolite is substituted by a cation selected from the group consisting of proton, ammonium, and metal cation of the groups IA, IB and IIA of the Periodic Table.

4. A process according to claim 3, wherein said cation is selected from the group consisting of lithium, sodium, potassium, magnesium, calcium, strontium, barium, copper, silver, gold, proton, and ammonium.

5. A process according to claim 1, wherein said desorbent is selected from the group consisting of chlorotoluene, dichlorobenzene, dichlorotoluene.