微生物对溶液中碘离子的吸附行为和机理探究  

STUDY OF THE CHARACTERIZATION AND THE MECHANISMS OF IODINE ION BIOSORPTION BY BAKER'S YEAST AND E. COLI

作　　者：姜筝 丰俊东[1] 

机构地区：[1]南京航空航天大学,江苏南京210016

出　　处：《水处理技术》2014年第9期34-38,共5页Technology of Water Treatment

摘　　要：为处理含放射性碘元素的核废水,通过改变作用时间、菌体投放剂量、溶液pH和溶液初始I-含量,分别研究面包酵母菌和大肠杆菌对I-的生物吸附行为,并对吸附机理进行探讨。结果表明,面包酵母菌和大肠杆菌对溶液中I-的吸附符合准1级、准2级动力学模型和Langmuir、Freundlich模型,吸附量的理论最大分别为120.7μmol/g和37.2μmol/g;傅里叶变换红外光谱仪分析发现面包酵母菌和大肠杆菌细胞壁上的氨基、羟基、羧基等基团参与了对I-的化学吸附过程;扫描电子显微镜分析发现吸附I-后,面包酵母菌和大肠杆菌都出现菌体细胞褶皱的现象,胞内物质也对于面包酵母菌和大肠杆菌对I-的后期吸附有一定的作用。In order to treat the nuclear wastewater containing radioactive iodine element, the removal of I- from aqueous solution by biosorption on Baker＇s yeast and E. coli was studied in batch mode. The equilibrium adsorptive quantity was determined to be a function of contact time, yeast dose, solution pH and initial concentration of I-. The experimental results obeyed well not only the Pseudo first order kinetics equation and Pseudo second order kinetics equation, but also the Langmuir and Freundlich model isotherms. According to the parameters of Langmuir isotherm, the maximum biosorption capacities of I- onto Baker＇s yeast and E. coli were 120.7 μmol/g and 37.2 μmol/g at 293 K, respectively. The binding capacity of Baker＇s yeast is greater than E. coll. Ion exchange is probably one of the main mechanisms during adsorptive process. The mechanism of I- binding by biomass was investigated by FTIR spectra and SEM. It turned out that chemical reaction might also be involved in adsorption.

关 键 词：生物吸附 面包酵母菌 大肠杆菌 I- 

分 类 号：X703.1[环境科学与工程—环境工程]