嗜麦芽窄食单胞菌对铜镉的吸附特性与离子交换  

Characteristic and Ion Exchanges During Cu^(2+) and Cd^(2+) Biosorption by Stenotrophomonas maltophilia

作　　者：白洁琼[1] 尹华[2,3] 叶锦韶[1] 彭辉[1] 唐立梼[1] 何宝燕[1] 李跃鹏[1] 

机构地区：[1]暨南大学环境工程系广东省高校毒害性污染物防治与生物修复重点实验室,广州510632 [2]华南理工大学环境科学与工程学院,广州510006 [3]工业聚集区污染控制与生态修复教育部重点实验室,广州510006

出　　处：《环境科学》2013年第1期217-225,共9页Environmental Science

基　　金：国家自然科学基金-广东省联合基金重点项目(U0933002);国家自然科学基金项目(50978122);暨南大学优秀本科推免生科研创新培育计划项目

摘　　要：研究了投菌量、金属浓度和戊二醛浓度对嗜麦芽窄食单胞菌吸附水体中Cu2+和Cd2+特性的影响,分析了重金属生物吸附、NO3-去除与菌体离子释放的关联,从离子吸附、交换、转化与释放的角度探讨了重金属生物吸附机制.结果表明嗜麦芽窄食单胞菌对Cu2+和Cd2+吸附性能良好,0.2 g·L-1干重菌体处理浓度为0.05 mmol·L-1的Cu(NO3)2和Cd(NO3)2溶液120 min后,Cu2+和Cd2+的吸附率分别达96.3%和83.9%.菌体对Cu(NO3)2和Cd(NO3)2溶液的吸附过程存在Cu2+和Cd2+的表面吸附与胞内运输、NO3-胞内积累、NO3-还原为NO2-等行为,而且Cu2+和Cd2+的胞内运输、NO3-积累和还原需要消耗能量,并会促进Cl-、PO43-、SO42-、Na+、NH4+、K+和Ca2+等离子的释放.红外光谱分析表明菌体酰胺基、羟基与羧基均参与了Cu2+和Cd2+的吸附.X-光电子能谱分析显示吸附后Cu2+和Cd2+的价态不发生变化.The characteristics of Cu2＋and Cd2＋ biosorption by Stenotrophomonas maltophilia（S.maltophilia） under different biomass,metal concentration and glutaraldehyde content were studied and the correlations among metal biosorption,NO-3 removal and ion release were analyzed.The mechanism was explored through ion biosorption,exchange,conversion and release.The experimental results demonstrated that S.maltophilia was an efficient strain to remove Cu2＋ and Cd2＋.The biosorption efficiencies of Cu2＋ and Cd2＋ achieved 96.3% and 83.9%,respectively after dealing with 0.05 mmol·L-1 aqueous solutions for 120 min with dry biosorbent dosage of 0.2 g·L-1.Cu2＋ and Cd2＋ biosorption by S.maltophilia included surface adsorption,transmembrane active transportation,bioaccumulation of NO3- and reduction of NO3- to NO2-.The intracellular transfer and reduction of NO3- to NO2- during biosorption by S.maltophilia were energy-consuming biological processes.It could also promote the release of Cl-,PO43-,SO42-,Na＋,NH＋4,K＋ and Ca2＋.From FTIR investigation,involvement of various functional groups like acetylamino,hydroxyl and carboxyl in the binding of Cu2＋ and Cd2＋was evident.Moreover,XPS results proved that the valence state of Cu2＋ and Cd2＋ did not changed by biosorption.

关 键 词：生物吸附 铜 镉 离子 嗜麦芽窄食单胞菌 

分 类 号：X172[环境科学与工程—环境科学]