Mo/HZSM-5催化剂上甲烷芳构化反应行为的改善—催化剂制备因素及反应物添加剂的考察  

Improvement of Methane Dehydroaromatization Performance over Mo/HZSM-5 Catalyst-Effects of Catalyst Preparation Methods and Reactant Additives

作　　者：陈会英[1] 李永刚[1] 陈为[1] 申文杰[1] 徐奕德[1] 包信和[1] 

机构地区：[1]中国科学院大连化学物理研究所催化基础国家重点实验室

出　　处：《分子催化》2005年第2期83-89,共7页Journal of Molecular Catalysis(China)

基　　金：国家重点基础研究发展规划(973计划)资助项目(G1999022406);BP-China"面向未来"清洁能源研究计划资助项目.

摘　　要：考察了6Mo/HZSM-5催化剂的不同制备因素对其甲烷芳构化反应性能的影响,包括甲烷气氛下以不同的程序升温速率(从600℃到700℃)预还原催化剂,及采用热溶液(70～80℃)浸渍制备催化剂等方法.在t=700℃,P=0.1MPa,SV=1500mL/(g-cat·h)的反应条件下,发现适当的程序升温速率预还原和热溶液浸渍制备等方法可以改善6Mo/HZSM-5催化剂的甲烷芳构化反应性能,提高催化剂的反应活性及稳定性.同时还考察了1.5%二甲醚作为反应物添加剂在不同反应温度、不同Mo担载量的HZSM-5催化剂上的甲烷芳构化反应性能,并与CO2,H2O的反应结果进行了对比.实验结果表明,在P=0.1MPa,SV=1500mL/(g-cat·h)的反应条件下,较高的反应温度及适量增加催化剂Mo担载量有利于进一步改善1.5%二甲醚/甲烷共进料情况下的芳构化反应行为;反应6h后催化剂的TEM照片显示,二甲醚与甲烷共进料改变了催化剂上积碳的形貌.Methane aromatization performance of different 6Mo/HZSM\|5 catalysts, which were prepared by changing the conditions of preparation, was investigated under the reaction conditions of t=700 ℃, P=0.1 MPa, SV=1 500 mL/(g-cat·h). It was found that the catalysts prepared by reducing Mo/HZSM-5 in CH_4 stream at a slower heating rate from 600 ℃ to 700 ℃ or by impregnating HZSM-5 power in hot (NH4)6Mo7O_24 solution (70 ~ 80 ℃) had a better catalytic activity and stability. The effects of 1.5% dimethyl ether (DME) as reactant additive to CH_4 feed were also investigated over Mo/HZSM-5 catalysts with different Mo loadings and at different temperatures. The results showed that higher reaction temperatures and higher Mo loadings were in favor of the aromatization of 1.5%DME/CH_4 co-feed under the reaction conditions of P=0.1 MPa and SV=1 500 mL/(g-cat·h). The TEM images of 6Mo/HZSM-5 catalysts coked for 6 h showed that the appearance of the coke was changed by 1.5%DME/CH_4 co-feed. The effects of 1.5% H_2O and 2.5% CO_2 co-reactants were also investigated and compared.

关 键 词：MO/HZSM-5 甲烷芳构化 二甲醚 CO2 H2O 

分 类 号：O643.32[理学—物理化学]