L沸石上氯苯的对位选择性氯化

PARA-SELECTIVE CHL ORINATION OF CHLOROBENZENE OVERL-ZEOLITE

测定了新型高效氯苯对位选择性氯化催化剂──Ｌ型沸石的催化性能。实验结果表明，Ｌｅｗｉｓ酸催化剂上对位选择性较低，如ＦｅＣｌ＿３的ｐ／ｏ（对、邻）比仅为１．５，而Ｌ沸石表现出高对位选择性，其ｐ／ｏ比达９．８，加入助剂（二氯乙酸）可使该值进一步提高到１２．８。反应温度控制在３６８～３７３Ｋ，助剂／Ｌ沸石／氯苯的质量比控制在１∶５∶５００左右最为适宜。此外，本文还对实验结果进行了初步解释。

Abstract PaFa-Chlorination of Chlorobenzene withchlorine was investigated by using L-zeolite ascatalyst. It was fotund that Lewis acid catalystssuch as FeCl_3 gave p/o ratio only 1.5,whereasL-zeolite exhibited good para-selectivity,withthe raftio about 9. 8 and even as high as 12.8when the cocatalyst, dichloroacetic acid, wascontained in the reaction system.Optimal re-sult was obtained when the reaction tempera-ture was between 368K and 373K and themass ratio of cocatalyst to L-zeolite tochlorobcnzene was about 1 to 5 to 500,respec-tively.In addition, the experiment results werediscussed briefly.