浮萍(Lemna aequinoctialis)干粉对Pb^(2+)的吸附  

Biosorption of Pb^(2+) by Dried Powder of Duckweed (Lemna aequinoctialis)

作　　者：陈兰钗 方扬[1,2] 靳艳玲[1,2] 陈谦[1,2,3,4] 赵永贵[1,2,3] 肖瑶[1,2,3] 赵海[1,2] 

机构地区：[1]中国科学院成都生物研究所,中国科学院环境与应用微生物重点实验室,成都610041 [2]中国科学院成都生物研究所,环境微生物四川省重点实验室,成都610041 [3]中国科学院大学,北京100049 [4]四川省原子能研究院生物技术研究所,成都610101

出　　处：《应用与环境生物学报》2013年第6期1046-1052,共7页Chinese Journal of Applied and Environmental Biology

基　　金：国家科技支撑计划项目(2011BAD22B03);中国科学院创新工程重要方向项目(KSCX2-EW-J-22;KSCX2-EW-G-1-1);中国科学院"西部之光"人才培养项目(Y2C5021100)资助~~

摘　　要：为开发高效去除重金属铅(Pb2+)污染的生物吸附剂,以浮萍(Lemna aequinoctialis)干粉为吸附剂原料,通过单因素实验研究了该吸附剂吸附Pb2+的主要影响因素;利用吸附动力学方程和等温吸附方程对实验数据进行拟合;并采用红外光谱分析仪研究了吸附前后吸附剂表面的化学基团变化.结果表明,对吸附效果影响显著的因素有溶液初始pH值、吸附剂颗粒大小和Pb2+初始浓度;参与吸附Pb2+的基团可能是吸附剂所含糖类中的羟基及酰胺中的氨基;其吸附行为符合准二级动力学方程,相关系数R2为0.999 95,k2为3.65 g min-1 mg-1;等温吸附曲线符合Freundlich方程,浮萍对Pb2+的吸附量在高达56.79 mg/g时仍未达到吸附饱和点.本研究表明L.aequinoctialis干粉作为一种新型生物吸附剂,对Pb2+的吸附条件要求不严格,吸附速率快,吸附容量大,在较宽的条件范围内都可达到较高的去除率.In order to develop efficient biosorbent material for Pb2＋ removal from wastewater, this study explored the biosorption of duckweed （Lemna aequinoctialis） powder. Single-factor experiments were designed to investigate the dominant effect on Pb2＋ removal. The experimental data were fitted with adsorption kinetics and isotherms to investigate the adsorption properties. The infrared spectroscopy was used to probe the surface characteristics of the sorbent. The results of single-factor experiments suggested that initial pH, grain size of sorbent and initial concentration of Pb2＋ had significant effects on the removal efficiency of Pb2＋. The infrared spectroscopy analysis indicated that the —OH groups of carbohydrate compounds and the —NH2 groups of amide compounds may be the main groups involved in the adsorption of Pb2＋ by the powder of L. aequinoctialis. This process followed the pseudo second-order kinetic with a correlation coefficient （R2） of 0.999 95 and the k2 of 3.65 g min-1 mg-1. The experimental data were well fitted with Freundlich isotherm model and the maximum Pb2＋ adsorption capacity was higher than 56.79 mg/g. This study suggested that the powder of L. aequinoctialis, as a new biosorbent material, has high Pb2＋ adsorption rate and capacity under various conditions.

关 键 词：浮萍 LEMNA aequinoctialis 生物吸附剂 铅污染 吸附动力学 红外光谱 

分 类 号：X173[环境科学与工程—环境科学]