黑藻吸附Cu^(2+)机制研究  

Study on Mechanisms of Cu^(2+) Biosorption by Aquatic Plant Hydrilla verticillata (L.f.) Royle

作　　者：薛培英[1] 李庆召 颜昌宙[1] 潘齐坤[1] 邱昭政[1] 张丹丹[1] 

机构地区：[1]中国科学院城市环境研究所城市环境与健康重点实验室,厦门361021 [2]郑州航空工业学院土木建筑学院,郑州450015

出　　处：《环境科学》2011年第6期1614-1619,共6页Environmental Science

基　　金：国家自然科学基金项目(20777059);福建省科技计划重点项目(2010Y0055)

摘　　要：生物吸附法是一种经济有效的去除废水中有害重金属离子的方法.以黑藻(Hydrilla verticillata)干样为生物吸附材料,研究了黑藻对水体中Cu2+等温吸附的基本特征,并通过测定吸附前后溶液离子浓度变化以及pH值、基团屏蔽对Cu2+吸附的影响,结合红外光谱技术,从静电吸附作用、离子交换作用、基团作用等方面探讨了吸附机制.等温吸附平衡实验结果表明,吸附等温线符合Freundlich、Langmuir和双Langmuir方程,其中Langmuir方程拟合最佳(p<0.01),黑藻对Cu2+的去除率为70%左右,最大吸附量为42.86 mg/g.吸附机制研究表明,静电吸附对黑藻吸附Cu2+起作用;吸附Cu2+后溶液中Ca2+质量浓度增加近2倍说明吸附过程中存在离子交换机制;黑藻表面羧基、氨基基团经化学屏蔽后,对Cu2+吸附量均降低10%左右(p<0.05),结合红外光谱确定酰胺基CO—NH2和离子化羧基COO-为黑藻与Cu2+发生络合作用的主要官能团.以上结果表明,黑藻主要通过静电吸附、离子交换、表面基团等的共同作用来有效去除水中的Cu2+,作为一种新的吸附剂用于工业废水中Cu2+的去除具有很好的发展前景.Biosorption is a kind of effective and economical method to get rid of heavy metals from polluted waters.The isotherm adsorption of Cu2＋ by Hydrilla verticillata（L.f.） royle was investigated.In addition,through testing cation concentrations before and after the isotherm adsorption as well as the effects of pH and blocking of functional groups on Cu2＋ adsorption abilities,mechanisms of Cu2＋ biosorption were discussed from several aspects such as electrostatic adsorption,ion exchange,complexation.Results indicated that biosorption equilibrium data were best described by Langmuir isotherm model followed by Freundlich model and Double Langmuir model.This adsorbent can remove about 70% of Cu2＋ and has the maximum adsorption capacity of 42.86 mg/g for Cu2＋.Moreover,electrostatic adsorption,ion exchange and functional groups are supposed to responsible for biosorption of Cu2＋.Through blocking functional groups combined with the analysis of FTIR,carboxyl and amino groups are confirmed to be the main active groups which were involved in the biosorption of Cu2＋.In conclusion,dried H.verticillata can provide a promising technology for eliminating copper from industrial effluents.

关 键 词：生物吸附 黑藻 CU2+ 基团屏蔽 吸附机制 

分 类 号：X52[环境科学与工程—环境工程]