【作者】 刘春洋； 熊亮亮； 张瑜； 蔡建国；

【Author】 Liu Chun-yang;Xiong Liang-liang;Zhang Yu;Cai Jian-guo;School of Chemical Engineering, East China University of Science and Technology;

【机构】 华东理工大学化工学院；

【摘要】 以正硅酸乙酯（TEOS）和甲基三甲氧基硅烷（MTMS）为硅源,采用溶胶-凝胶、超临界乙醇干燥法将钌负载于硅气凝胶,制备出载钌硅气凝胶催化剂。在硅气凝胶制备过程中,凝胶时间受制备条件影响,其中溶液pH对凝胶时间影响最大,凝胶时间随着pH值升高而减小,溶液pH控制在7～7.5较好。对制备出的硅气凝胶密度和体积收缩率影响最大的是硅源的组成,其次是乙醇的用量。通过对表征结果进行分析,发现使用溶胶-凝胶法制备的载钌硅气凝胶孔隙率高,比表面积达到700 m²/g以上,平均孔径49nm,在干燥过程中Ru³⁺离子被超临界乙醇还原成0价,Ru金属粒径为10nm左右,均匀分散在载体上,没有出现团聚。更多还原

【Abstract】 Ethyl orthosilicate（TEOS）and methyl trimethoxysilane（MTMS）were used as raw materials to prepare the Ru-silica aerogel catalyst by sol-gel and supercritical drying method.In the process of preparing silica aerogel,gelation time is affected by many factors.The pH of the solution has the greatest influence on gelation time.Gelation time decreases when solution pH increases,the most appropriate pH is between 7-7.5.The composition of the silicon source has the greatest influence on the density and volume shrinkage of silica aerogel,followed by the amount of ethanol.The catalyst prepared by sol-gel and supercritical drying method is homogeneous with high specific surface area（700 m²/g）.The average pore diameter is 49 nm.Supercritical ethanol can convert Ru³⁺ to Ru⁰ by it’s strong reducing property.The particle size of Ru was about 10 nm and it was uniformly dispersed on the silica aerogel without agglomeration.更多还原