| 摘要 |
PURPOSE:To obtain the titled p- and/or m-isomers, ecomomically, by using a specific diluent in the isomerization of o-chlorotoluene, and carrying out the steps comprising the isomerization, separation by distillation, recycling of the diluent, separation by adsorption, and recycling of the isomer mixture. CONSTITUTION:A mixture 1 of chlorotoluene isomers containing o-chlorotoluene or its isomers is supplied to the isomerization stage 4 together with an aromatic diluent 2 having lower boiling point than the isomer 1, and at least a part of the isomer is converted to p- and m-chlorotoluene. The effluent liquid 5 is separated by distillation 6 to recover the diluent 2 and the mixture 7 of chlorotoluene isomers 7. The diluent 2 is recycled to the isomerization stage 4, and the isomer mixture 7 is supplied to the adsoprption stage 10 to recover the p- or m-chlorotoluene useful as a raw material of pesticides. At least a part 3 of the residual isomer mixture 15 is recycled to the isomerization stage 4. |
