乙二胺在ZSM-5分子筛催化剂上脱氨制哌嗪

STUDY OF DEAMINATION OF ETHYLENEDIAMINE TO PIPERAZINE ON ZSM 5 ZEOLITE CATALYSTS

研究了反应温度、反应物浓度及空速对乙二胺在ＨＺＳＭ５和ＫＺＳＭ５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２３ｈ－１条件下，乙二胺在２６％ＫＺＳＭ５催化剂上的转化率为９５％，哌嗪的选择性为９６％．与此同时，用ＮＨ３ＴＰＤ和吡啶ＩＲＴＰＤ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．

Deamination of ethylenediamine (EDA) to piperazine (PA) over H ZSM 5 and K ZSM 5 zeolite catalysts has been studied. The effects of reaction temperature, reactant concentration and space velocity on the catalytic performance of H ZSM 5 and K ZSM 5 have been investigated. It is found that EDA conversion is 95% and PA selectivity is 96%, when using 2 6%K ZSM 5 with SV 2 3 h -1 , w (EDA)=50% and 340℃. At the same time, NH 3 TPD profiles and Py IR spectra show that the weaker Lewis acidic sites in the zeolite are the active centers. Further, the catalytic reaction process and its mechanism have been discussed.