焙烧温度对甲硫醇催化剂K_2WO_4/Al_2O_3结构和性能的影响  

Effect of Calcination Temperature on the Structure and Catalytic Performance of K_2WO_4/Al_2O_3 Catalysts for Methanethiol Synthesis

作　　者：张元华[1] 陈世萍[1] 袁成龙[1] 方维平[1] 杨意泉[2] 

机构地区：[1]厦门大学化学化工学院化学工程与生物工程系,福建厦门361005 [2]厦门大学化学化工学院化学系,醇醚酯清洁生产国家工程实验室,福建厦门361005

出　　处：《催化学报》2012年第2期317-322,共6页

基　　金：重庆紫光化工股份有限公司的经费资助

摘　　要：研究了焙烧温度对溶胶-凝胶法制备的甲硫醇催化剂K2WO4/Al2O3的表面结构和催化性能的影响.表征结果显示,K2WO4在Al2O3上分散得较好,在450和550oC焙烧的催化剂颗粒大小均匀,无明显团聚现象.随着焙烧温度的升高,催化剂的比表面积减小,表面钨物种与Al2O3的相互作用减弱,与碱物种的相互作用增强,酸碱强度降低.K2WO4/Al2O3表面不含质子酸.催化剂活性与其比表面积及表面的共轭酸碱对密切相关.评价结果表明,在550oC焙烧而制得的催化剂活性最高.The effect of calcination temperature on the surface morphology and catalytic performance of the K2WO4/Al2O3 catalyst prepared by the sol-gel method for the synthesis of methanethiol from methanol and hydrogen sulfide was investigated.Physicochemical characterization results of the catalyst showed that the K2WO4 is well dispersed on Al2O3,and the catalyst possesses uniform particle size after calcination at 450 or 550 oC.With increasing the calcination temperature,the specific surface area decreases,the interaction of W species with Al2O3 was weakened,but strengthened with basic species,leading to the decrease of surface acidity and basicity.No Brnsted acid was found on the catalyst surface.The catalytic activity of the catalyst is closely related with the specific surface area and the presence of conjugate acid-base pairs on the surface.Activity assay results show that the catalyst calcined at 550 oC exhibits the highest activity for the reac-tion.

关 键 词：钨酸钾 氧化铝 负载型催化剂 甲硫醇 甲醇 硫化氢 

分 类 号：O643.36[理学—物理化学]