酚醛基炭气凝胶对银离子的吸附性能研究  

Adsorption and Reduction of Silver Ions onto Carbon Aerogels

作　　者：王海清[1] 张淑婷[1] 余敏娜[1] 符若文[2] 

机构地区：[1]华南农业大学理学院,广东广州510642 [2]中山大学材料科学研究所,广东广州510275

出　　处：《华南农业大学学报》2008年第3期101-106,共6页Journal of South China Agricultural University

基　　金：国家自然科学基金项目(50133020);广东省科技计划项目(2004A30404001)

摘　　要：以4种经常压干燥法制备的酚醛基炭气凝胶(carbon aerogels,CAs)为原料,通过静态和动态吸附试验及扫描电镜(SEM)表征,研究了材料孔结构、表面特性及溶液性质等因素对Ag+吸附性能的影响.结果表明,Ag+在炭气凝胶表面的吸附主要是以氧化还原形式进行的化学吸附,通过还原吸附的银颗粒主要分布在凝胶外表面,而吸附容量与孔结构、活化程度(表面活性还原官能团)、溶液pH、固液比例及Ag+浓度等有关.SEM图表明在不同pH的硝酸银溶液下吸附于凝胶表面的银状态不同.Four kinds of carbon aerogels prepared by ambient the capability of adsorption silver ions onto carbon aerogels by pressure technique were used to investigate static and dynamic adsorption experiment. The effects of pore size, the Brunauer-Emmett-Teller（BET） surface area, the initial AgNO3 concentration, the ratio of aerogel mass/solution volume and value on adsorption properties were studied. The morphology of silver-containing carbon aerogels were investigated by means of scanning electron microscopy （SEM）. The results showed that the mechanism of silver ions adsorption onto carbon aerogels is conducted by way of oxidation and reduction reaction. The adsorbent granule silver was distributed mainly on the surface of carbon aerogels, and adsorption capacity of silver was related to pore structure, the extent of activation, solution pH, the ratio of aerogel mass/solution volume, Ag^＋ concentration and so on. The SEM figures showed that the state of silver adsorbed on the surface of carbon aerogels was various in the solution of different pH.

关 键 词：炭气凝胶 还原吸附 银离子 

分 类 号：O632.72[理学—高分子化学]