天然水优势菌胞外聚合物及主要成分对Cd^(2+)的吸附特征  

Cadmium Adsorption by Extracellular Polymers and Main Components of Superiority Bacteria in Natural Water

作　　者：苏春彦[1] 康春莉[1] 郭平[1] 董德明[1] 

机构地区：[1]吉林大学环境与资源学院

出　　处：《应用化学》2006年第11期1185-1189,共5页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(20077011);吉林大学创新基金(450011022018)资助项目

摘　　要：利用原子吸收法,研究了长春市南湖天然水环境中生物膜优势菌种的胞外聚合物及其主要成分胞外多糖和胞外蛋白对Cd2+的吸附特性,讨论了时间、pH值、其它共存金属离子等对其吸附反应的影响。利用红外光谱分析法对吸附反应机理进行了初步探讨。结果表明,胞外聚合物、胞外多糖和胞外蛋白对Cd2+的吸附均在pH=6时吸附量最大;对Cd2+的吸附均在6 h以后达到平衡;共存金属离子如Pb2+对Cd2+的吸附有干扰。对Cd2+的吸附过程符合Langmu ir和Freund lich热力学方程。3种吸附剂对Cd2+的吸附能力为:胞外聚合物>胞外多糖>胞外蛋白。胞外蛋白的胺基、酰胺基,胞外多糖的羟基、酰胺基等在吸附Cd2+过程中是起关键作用的化学基团。The adsorption of cadmium （ The exopolysaccharide and extracellular bacteria of natural biofilm cultivated in Ⅱ） on protein Change the extracellular polymers of natural biofilm was investigated. were obtained from the extracellular polymers of superiority hun South Lake. The results show that both Langmuir and Freundlich isotherm equations could describe the thermodynamic adsorption processes of Cd^2＋ on the extracellular polymers, exopolysaccharide and extracellular protein. The existence of Pb^2＋ affects the adsorption of Cd^2＋ while pH affect the adsorption processes. The mechanism of Cd^2＋ adsorption was studied by means of infrared spectra and the functional groups participated in the adsorption were identified. These groups could be acetylamino group（-NHCOCH3 ） and amino-group （-NH2 ） of protein, hydroxyl group （-OH） of exopolysaccharide, etc. The results show that the biosorption ability of the exopolysaccharide is much higher than that of the extracellular protein in the extracellular polymers

关 键 词：优势菌种 胞外聚合物 镉 吸附 

分 类 号：O652[理学—分析化学]