摘要
采用水热包覆法和物理共混法分别制备了ZSM-5@t-ZrO_(2)和ZSM-5/t-ZrO_(2)复合催化剂,并以ZSM-5和t-ZrO_(2)为对比参考,研究了不同结构催化剂的物化性质和催化性能。在此基础上,借助漫反射傅里叶变换红外光谱,考察了反应温度和预硫化操作对ZSM-5@t-ZrO_(2)复合催化剂上甲醇和硫化氢反应分子吸附转化的影响。结果表明,水热包覆环境修饰了ZSM-5@t-ZrO_(2)复合催化剂的物化性质,提升了甲醇硫醇化反应的催化性能和抗积碳积硫失活能力。在反应压力1 MPa、反应温度380℃、预硫化1 h、N_(2)流量100 mL/min的条件下,甲醇转化率、甲硫醇选择性及甲硫醇收率分别达到92.02%、90.56%和82.76%。硫化氢分子在ZSM-5@t-ZrO_(2)催化剂的碱位上吸附解离为巯基,进而攻击甲氧基,这是甲硫醇合成反应的速率控制步骤。380℃的反应温度和预硫化操作有助于构建形成匹配的甲氧基和巯基生成速率,在提高催化性能的同时还可有效降低积碳积硫形成速率。
The composite catalysts of ZSM-5@t-ZrO_(2)and ZSM-5/t-ZrO_(2)were prepared by hydrothermal coating method and physical blending method,respectively.Taking catalysts of t-ZrO_(2)and ZSM-5 as reference,catalytic performance,physical and chemical properties of the composite catalysts with different structures were studied.On this basis,the effects of reaction temperature and presulfurization operation on the adsorption and conversion characteristics of methanol and hydrogen sulfide on ZSM-5@t-ZrO_(2)composite catalyst were studied by means of diffuse reflectance Fourier transform infrared spectroscopy.The results show that hydrothermal coating process modified the physical and chemical properties of ZSM-5@t-ZrO_(2)composite catalyst,thus improves the catalytic performance and deactivation resistance of carbon and sulfur deposition of methanol thiolation reaction.Under the conditions of reaction pressure of 1.0 MPa,reaction temperature of 380℃,presulfurization for 1 h and N_(2)flow rate of 100 mL/min,the methanol conversion,methanethiol selectivity and methanethiol yield are 92.02%,90.56%and 82.76%,respectively.The rate control step of the thiolation reaction is the adsorption and dissociation of hydrogen sulfide molecules on the base sites of of ZSM-5@t-ZrO_(2)catalyst into sulfhydryl groups and then attacking methoxy groups.The reaction temperature of 380℃and presulfurization operation are helpful to build the matching formation rate of sulfhydryl groups and methoxy groups,which not only enhances the catalytic performance but also reduces the formation rate of carbon and sulfur deposition effectively.
作者
裴丽洁
刘飞
曹建新
杨安杰
姚梦琴
刘飘
PEI Lijie;LIU Fei;CAO Jianxin;YANG Anjie;YAO Mengqin;LIU Piao(School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China;Key Laboratory for Green Chemical and Clean Energy Technology of Guizhou Province,Guizhou University,Guiyang 550025,China;Engineering Research Center for the High Efficiency Utilization of Industrial Wastes of Guizhou Province,Guizhou University,Guiyang 550025,China)
出处
《硅酸盐通报》
CAS
北大核心
2022年第8期2927-2934,共8页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金项目(21666007)
贵州省科技创新人才团队(黔科合平台人才[2018]5607)
贵州省百层次创新型人才专项(黔科合平台人才[2016]5655)
贵州省教育厅创新群体项目(黔教合KY字[2021]010)。
