摘要
采用浸渍法制备了负载MnO的SAPO-34分子筛(MnO/SAPO-34)催化剂,在固定床反应器中对催化剂的乙醇脱水制乙烯的催化性能进行了评价,采用低温N2吸附-脱附、XRD、NH3-TPD和H2-TPR等方法对催化剂进行了表征。实验结果表明,负载适量MnO不会破坏SAPO-34分子筛的骨架结构,但对表面酸性及酸量产生了一定的影响,降低了SAPO-34分子筛上弱酸与强酸的酸量,有利于提高催化剂的乙醇脱水性能;当MnO负载量为1.29%(w)时,在反应温度300℃、乙醇重时空速3.16 h-1的条件下,乙醇转化率和乙烯选择性分别可以达到99.99%和99.74%。
MnO/SAPO-34 catalysts with different MnO loadings were prepared by an impregnation method and characterized by means of N2 adsorption-desorption, XRD, NH3-TPD and H2-TPR. The activity of the catalysts in the dehydration of ethanol to ethylene was investigated. The results showed that the addition of an appropriate amount of MnO would not destroy the framework structure of SAPO- 34 but change its surface acidity. Increasing the ratio of the weak acid sites to the strong acid sites on the catalysts would improve the catalyst activity in the ethanol dehydration. Under the optimized conditions of 1.29%（w） MnO/SAPO-34 as the catalyst, reaction temperature of 300 ℃ and WHSV of 3.16 hl, the ethanol conversion and ethylene selectivity could reach 99.99% and 99.74%, respectively.
出处
《石油化工》
CAS
CSCD
北大核心
2013年第5期483-488,共6页
Petrochemical Technology
