不同制备工艺和载体上负载银催化剂的银粒表观形貌  

The Morphology of Silver Crystallites on Supported Silver Catalysts Prepared by Various Methods and Carriers

作　　者：朱孟钦 张式[2] 

机构地区：[1]华东理工大学技术化学物理研究所 [2]中国石油化工总公司上海石油化工研究院

出　　处：《电子显微学报》1997年第2期157-164,共8页Journal of Chinese Electron Microscopy Society

摘　　要：本文利用不同的制备工艺和载体采用络合液浸渍法和液相还原法制备了负载银催化剂，并用热分析技术（ＴＧＡ、ＤＴＡ）考察了催化剂的热处理过程，用扫描电子显微镜（ＳＥＭ）观察了不同条件下制备的负载银催化剂的银粒表观形貌结构。结果表明，以不同的起始银化合物利用络合液浸渍法制备的浸渍物，其热处理过程都具有明显的干燥与分解还原两个阶段，最终催化剂的银粒表观形貌无明显差别，液相还原法制得的负载银粒存在双峰分布。载体的物理结构变化没有大大改变银粒的表观形貌，但其表面化学性质却明显地改变了银粒的聚集形状。热处理条件的改变对银粒表观形貌结构的影响最为显著，它不仅改变银粒的形态。The supported silver catalysts were prepared by various methods on different carriers through impregnation of silver ammine complex solution and direct liquid phase reduction. Thermal analysis Techniques (TGA, DTA) had been used to investigate the thermal decomposition of the catalyst samples. The morphology of silver crystallites of supported silver catalysts had been observeved by means of Scanning Electron Microscope (SEM). The results show that the thermal decomposition has two stages, ie. dry and decomposition stages. A bimodal distribution of crystallite size has been found for the catalyst prepared by liquid phase reduction. The physical structure of the carriers almost does not affect the morphology of crystallites, but the chemical properties of carrier surface obviously change their coagulation state. The thermal treatment is the most important factor for the morphology of crystallites.

关 键 词：银 催化剂 表观形貌 负载银催化剂 

分 类 号：O643.36[理学—物理化学]