乙醇胺为碱性催化剂对硅气凝胶性能的影响  

Effect of ethanolamines as alkalescence catalysts on properties of silica aerogel

作　　者：王雪枫[1] 黄雪莉[1] 王毅[2] 

机构地区：[1]新疆大学化学化工学院,新疆乌鲁木齐830046 [2]新疆乌鲁木齐市气象局

出　　处：《无机盐工业》2011年第9期13-16,45,共5页Inorganic Chemicals Industry

基　　金：国家自然科学基金资助项目(21067013)

摘　　要：以正硅酸乙酯为硅源,盐酸为酸性催化剂,乙醇胺(一乙醇胺、二乙醇胺、三乙醇胺)、氨水为碱性催化剂,采用酸碱两步催化溶胶-凝胶法制备二氧化硅湿凝胶,凝胶不经过表面改性,采用真空干燥制得二氧化硅气凝胶。通过对二氧化硅气凝胶样品进行比表面积测定和扫描电镜观察,表明添加不同的乙醇胺所得二氧化硅气凝胶的性能不同。采用乙醇胺作催化剂与氨水作比较所得二氧化硅气凝胶平均孔径较大。采用一乙醇胺作催化剂与氨水作比较,在添加量为(5.1～8.5)×10-2mol时,所得二氧化硅气凝胶的吸附能力提高,内表面粗糙度减小,孔隙率提高,减轻了孔壁的坍塌。采用二乙醇胺作催化剂与其他碱性催化剂作比较,随着其添加量的增加所得二氧化硅气凝胶平均孔径增加幅度较大。采用三乙醇胺作催化剂与其他碱催化剂相比,所得二氧化硅气凝胶的内部表面最粗糙。With tetraethyoxysilane（TEOS） as silicon source,hydrochloric acid as acidic catalyst,and ethanolamines（monoethanolamine,diethanolamine,and triethanolamine）and ammonia as alkalescence catalysts,wet silica aerogel was prepared by acid/base two-step catalytic process sol-gel method.Silica aerogel was then prepared by vacuum drying without surface modification.Physical properties and structures of the prepared samples were characterized by BET and SEM etc..Results showed different ethanolamines can make different properties of silica aerogel.Comparing with ammonia,silica aerogel had larger average aperture if ethanolamines as catalyst;comparing with ammonia,adsorbing ability and porosity of silica aerogel was increased,harshness of internel surface was decreased,and the wall collapse of hole was lightened if monoethanolamine as catalyst and the dosage was（5.1～8.5）×10^-2 mol;comparing with other basic catalysts,diethanolamine can make bigger increase on the mean pore size of silica aerogel;comparing with other basic catalysts,triethanolamine made the roughest internal surface.

关 键 词：二氧化硅气凝胶 乙醇胺 碱性催化 

分 类 号：TQ127.2[化学工程—无机化工]