相转移催化水解联产邻、对氯苯甲醛的工艺研究

Study on joint process of o-chlorobenzaldehyde and p-chlorobenzaldehyde by phase-transfer catalytic hydrolysis

邻、对氯苯甲醛的传统生产工艺分别采用邻、对氯甲苯作为原料,然而邻、对氯甲苯沸点非常相近,分离困难。根据邻、对氯苯甲醛熔点差别大的特性,本文提出以混合邻、对氯甲苯为原料联产邻、对氯苯甲醛的新工艺路线,该工艺避免了混合邻、对氯甲苯的分离工艺,可以大大节省分离能耗。本文重点研究了采用相转移催化水解邻、对氯苄叉二氯混合物同时制备邻、对氯苯甲醛的工艺,考察了催化剂用量、水量及原料配比对反应的影响,确定了适宜的水解反应工艺条件,为以邻、对氯甲苯混合物作原料同时制备邻、对氯苯甲醛的联产工艺开发奠定基础。

O - chlorobenzaldehyde and p - chlorobenzaldehyde were manufactured from o - chlorotoluene and p - chlorobenzene respectively at present, however, the separation of o - chlorotoluene and p - chlorotoluene was difficult because of the closing - boiling of them. Owing to the great difference in melt point of o - chlorobenzaldehyde and p - chlorobenzaldehyde, a novel joint process of o - chlorobenzaldehyde and p - chlorobenzaldehyde from mixture of o - chlorotoluene and p - chlorotoluene was brought forward, and the separation of mixture of o - chlorotoluene and p - chlorotoluene was avoided, so the consumption of separation energy was decreased enormously. The simultaneously prepared method of o - chlorobenzaldehyde and p - chlorobenzaldehyde by phase -transfer catalytic hydrolysis of mixture of o - chlorobenzal chloride and p - chlorobenzal chloride was investigated in this article. The effects of amount of catalyst, amount of water and ratio of raw materials on the reaction rate were studied, and the optimal hydrolysis condition was obtained. On this basis, it was possible to establish a joint process of o - chlorobenzaldehyde, p - chlorobenzaldehyde using the mixeutr of o - chlorotoluene and p - chlorotoluene as materials.