无模板剂合成束状多级孔ZSM-5分子筛及其催化剂的甲烷无氧芳构化反应性能研究  

Template-free synthesis of bundle-like hierarchical ZSM-5 zeolites and its catalytic performance for nonoxidative methane dehydroaromatization

作　　者：甘海波 叶枫 吕义辉 樊栓狮[1] 郎雪梅[1] 王燕鸿[1] 姚晔 李刚 GAN Haibo;YE Feng;LV Yihui;FAN Shuanshi;LANG Xuemei;WANG Yanhong;YAO Ye;LI Gang(School of Chemistry and Chemical Engineering,South China University of Technology,Guangzhou 510641,Guangdong,China;Zhuhai Institute of Modern Industrial Innovation,South China University of Technology,Zhuhai 519175,Guangdong,China)

机构地区：[1]华南理工大学化学与化工学院,广东广州510641 [2]华南理工大学珠海现代产业创新研究院,广东珠海519175

出　　处：《天然气化工—C1化学与化工》2022年第4期92-98,共7页Natural Gas Chemical Industry

基　　金：国家自然科学基金(U1662137);珠海市产学研合作及基础与应用研究项目(ZH22017003210078PWC)。

摘　　要：甲烷无氧芳构化(MDA)是甲烷直接转化和利用的重要途径,高性能催化剂的制备是MDA研究的重点。在无模板剂的含氟合成液中,通过添加晶种成功合成出了一种束状多级孔ZSM-5分子筛,然后基于该分子筛采用浸渍法制得Mo/HZSM-5-H催化剂,并对其在MDA中的反应性能进行了评价。结果表明,Mo/HZSM-5-H的介孔孔容为0.09 cm^(3)/g,其总酸量达到176.03μmol/g,且Brönsted酸量和Lewis酸量之比为0.822,表明Mo/HZSM-5-H具有明显的介孔特征和较为理想的酸位分布。Mo/HZSM-5-H的甲烷转化率最高为14%,苯产率最高为6.8%,反应过程中无甲苯和二甲苯生成。与常规的微孔Mo/HZSM-5-C和球形多级孔Mo/HZSM-5-S相比,Mo/HZSM-5-H具有更高的催化活性和非常狭窄的芳烃产物分布,在高效制备苯这一重要大宗化学品方面有较好的应用前景。Nonoxidative methane dehydroaromatization(MDA)reaction is an important way for direct conversion and utilization of methane,and the preparation of high-performance catalysts has been the focus of the research.Bundle-like hierarchical ZSM-5 zeolites were successfully synthesized with addition of ZSM-5 seeds in a fluorine-containing solution free of template.Then the catalyst Mo/HZSM-5-H based on bundle-like hierarchical ZSM-5 zeolites was prepared by an impregnation method and its catalytic performance in MDA was evaluated.The results show that the mesoporous volume of Mo/HZSM-5-H is 0.09 cm^(3)/g and its total acid amount reaches 176.03μmol/g,and the ratio of Brönsted acid to Lewis acid is 0.822,which indicate that Mo/HZSM-5-H catalyst obviously has a hierarchical structure and an ideal acid distribution.The bundle-like hierarchical Mo/HZSM-5-H catalyst shows the highest methane conversion of 14%and the best benzene yield of 6.8%,and no toluene or xylene are generated during the reaction.Compared with conventional microporous Mo/HZSM-5-C and spherical-shaped hierarchical Mo/HZSM-5-S catalysts,the Mo/HZSM-5-H catalyst has a higher catalytic activity and a very narrow aromatic product distribution,which shows a good application prospect in the efficient production of benzene that is an important bulk che mical.

关 键 词：甲烷转化 无模板法 多级孔道ZSM-5 束状分子筛 甲烷无氧芳构化 催化剂合成 

分 类 号：TQ426[化学工程] TQ241