研究了反应温度、反应物浓度及空速对乙二胺在ＨＺＳＭ５和ＫＺＳＭ５分子筛催化剂上转化为哌嗪反应的影响．在反应温度为３４０℃，乙二胺浓度为５０％和空速为２３ｈ－１条件下，乙二胺在２６％ＫＺＳＭ５催化剂上的转化率为９５％，哌嗪的选择性为９６％．与此同时，用ＮＨ３ＴＰＤ和吡啶ＩＲＴＰＤ确定反应是在弱酸部位Ｌ酸中心上进行的，并依此推测了反应机理． The effects of reaction temperature, reactant concentration and space velocity on the reaction of ethylenediamine to piperazine on HZSM5 and KZSM5 zeolites were investigated. Under the conditions of reaction temperature of 340 ℃, ethylenediamine concentration of 50% and space velocity of 23h-1, the conversion of ethylenediamine on 26% KZSM5 catalyst was 95% The selectivity is 96%. At the same time, NH3TPD and pyridine IRTPD were used to confirm the reaction was carried out on the L acid sites of the weak acid sites, and the reaction mechanism was speculated accordingly.