摘要
采用介孔γ-Al2O3对微孔SAPO-34分子筛进行复合改性,利用水热包覆技术制备了γ-Al2O3/SAPO-34复合催化剂,研究了复合催化剂物化性质及其对甲醇制低碳烯烃(MTO)反应的催化性能。采用X射线衍射仪(XRD)、傅里叶红外光谱仪(FT-IR)、扫描电子显微镜(SEM)、氨气程序升温脱附法(NH3-TPD)和物理吸附仪(BET)等手段对不同γ-Al2O3/SAPO-34复合催化剂的晶相组成、骨架结构、微观形貌、表面酸性及孔结构进行分析表征。结果表明,与物理共混催化剂相比,水热包覆法制得γ-Al2O3/SAPO-34复合催化剂形成了包覆相和微-介孔结构(微孔比表面积123m^2/g,介孔比表面积95m^2/g)。在常压、催化剂装载量1g、水/醇摩尔比2/1、原料进料体积空速2h-1、N2流速20mL/min、反应温度380℃条件下,复合催化剂表现出优越的催化性能和反应寿命,甲醇转化率和低碳烯烃选择性分别达到100%和88%,催化剂寿命达到990min,与物理共混催化剂相比,复合催化剂寿命延长了640min。
Microporous SAPO-34 molecular sieve was promoted by mesoporous γ-Al2O3 via hydrothermal coating route to prepare γ-Al2O3/SAPO-34 composite catalyst,and the physicochemical properties and catalytic performance in methanol to lower olefin (MTO) of the composite catalysts were investigated.These obtained composite catalysts were extensively characterized by X-ray diffraction (XRD),fourier transform infrared spectroscopy (FT-IR),scanning electron microscope (SEM),NH 3-temperature programmed desorption (NH 3-TPD) and Brunner Emmet Teller (BET) techniques,to investigate their crystalline phase,skeletal structure,morphology,surface acidity and pore structure,respectively.Compared with the physically blending catalyst,the uniformly continuous coating phase and micro-mesoporous structure (microporous specific surface area of 123 m^2/g,mesoporous specific surface area of 95 m^2/g) were successfully obtained in the composite catalyst.The composite catalyst exhibits superior catalytic performances and reaction life-time,with methanol conversion of 100%,light olefins selectivity of 88%,and catalytic lifetime of 990 min under the conditions of atmospheric pressure,reaction temperature of 380 ℃,catalyst loading of 1 g,hydro/alcohol molar ratio of 2/1,nitrogen flow rate of 20 mL/min and feed speed of 2 h^-1.Compared with the physically blending catalyst,the catalytic lifetime of the composite catalyst is extended by 640 min.
作者
陈莎
刘飞
罗兰
曹建新
CHEN Sha;LIU Fei;LUO Lan;CAO Jianxin(School of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China;Guizhou Key Laboratory for Green Chemical and Clean Energy Technology,Guiyang 550025,China;Guizhou Key Laboratory for Efficient Utilization of Mineral and Green Chemical Technology,Guiyang 550025,China)
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2019年第4期644-652,共9页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学基金项目(21666007)
贵州省百层次创新型人才专项(黔科合平台人才[2016]5655)
贵州省科技创新人才团队(黔科合平台人才[2018]5607)
贵州省科技计划项目(黔科合平台人才[2017]5788号)资助
