| 摘要 |
1,3-dihalobenzene, particularly 1,3-dichlorobenzene, is produced in high efficiency from a mixture containing the subject compound and its corresponding 1,4-isomer by a special process in which the dihalobenzene mixture is treated with polyethylene glycols of varying molecular weight and the resulting slurry is filtered to remove a complex of 1,4-dihalobenzene and polyethylene glycol as a solid and the 1,3-dihalobenzene as the filtrate. The 1,4-dihalobenzene complexed with the polyethylene glycol can be recovered by a flash distillation under vacuum and the residue containing the polyethylene glycol can be recycled. The purity of the 1,3-dihalobenzene obtained by this process can further be improved by subjecting the product obtained after the polyethylene glycol treatment to a low temperature crystallization process where 1,3-dihalobenzene can be selectively crystallized to a purity of above 99%. |
