对氯甲苯环上氯化制备3,4-和2,4-二氯甲苯

PREPARATION OF 3,4 DICHLOROTOLUENE AND 2,4 DICHLOROTOLUENE FROM CATALYTIC CHLORINATION OF PARA CHLOROTOLUENE

采用复合催化剂使对氯甲苯催化氯化制取２，４－和３，４－二氯甲苯时，氯化液中的３，４－二氯甲苯与２，４－二氯甲苯的摩尔比从过去的单一催化剂时的０．２５提高到０．３６～０．５８。用正交试验法研究确定最佳反应条件为：反应温度３０３Ｋ，催化剂用量１％（质量分数），通氯速率０．２６５５Ｌｍｉｎ－１Ｌ－１，反应结果为：对氯甲苯的单程转化率５２．７９％，３，４－二氯甲苯收率１３．３％，联产２，４－二氯甲苯的收率３５．８％，多氯物的质量分数２．５５％。

dichlorotoluene and 2,4 dichlorotoluene are prepared from para chlorotoulene by catalytic chlorination with a complex catalyst, molar ratio of 3,4 DCT/2,4 DCT is 0.36～0.58 versus 0.25 with a single catalyst. The optimum reaction condition is: reaction temperature 303 K, catalyst amount 1.0%, flow rate of chlorine 0.265 5 L·min 1 ·L -1 ,and the result is :percent convertion of PCT 52.79% ,yield of 3,4 DCT 13.3% , 2,4 DCT 35.8%, polychloro compounds 2.55%.