K-L分子筛对甲苯芳环氯化选择性的影响

Effect of K-L Zeolite on Selectivity of Toluene Aromatic Chlorination

以K-L分子筛为催化剂,催化氯化甲苯制备邻/对氯甲苯,考察催化剂用量、粒径、重复使用次数、及溶剂等工艺条件对氯化选择性的影响。较优条件:氯化温度55℃,反应时间4h,催化剂粒径200目,K-L分子筛=10.0%,1,2-二氯乙烷=40.0%。在此条件下,甲苯转化率为99.8%,对氯甲苯选择性为84.1%,其催化性能优于工业常用的硫铁粉催化剂。

o/p-Chlorotoluene was prepared by chlorinating toluene using K-L zeolite as catalyst.The effects of technological factors on chlorination selectivity were studied,such as catalyst amount,grain diameter,solvent and recycle of catalyst.The optimum conditions were as follows：chlorination at 55℃,reaction time of 4h,K-L zeolite=10.0%,1,2-dichloroethylene=40.0%,catalyst grain diameter of 200 mesh.Under optimal conditions,the conversion of toluene was 99.8% and the selectivity of p-chlorotoluene was 84.1%.The performance of K-L zeolite was superior to the sulfogen catalyst.