巯基乙胺改性蛭石对水体中Ag(I)的吸附性能研究  

Efficient removal of silver from aqueous solution with vermiculite modification by 2-aminoethanethiol

作　　者：陈理想[1,2] 吴平霄[1] 杨林[1] 祝雅杰[1] 

机构地区：[1]华南理工大学环境与能源学院、工业聚集区污染控制与生态修复教育部重点实验室,广东广州510006 [2]广平大学,越南广平

出　　处：《中国环境科学》2015年第4期1109-1115,共7页China Environmental Science

基　　金：国家自然科学基金(41273122,41073058,40973075)

摘　　要：用巯基乙胺（MEA）来改性天然蛭石,并利用FTIR、BET、TG-DSC等手段对蛭石和改性蛭石进行表征,分析结果显示MEA成功负载到蛭石上.同时,研究改性蛭石对Ag＋的吸附性能,结果表明,经过巯基乙胺改性后蛭石的吸附能力得到较大提升Ag＋的去除率从20%提升到79%,吸附大约在200min达到平衡,吸附剂最佳投加量为2g/L左右,p H值在6～12范围内都有较好的吸附效果.Langmuir等温吸附模型和准二级动力学模型能够很好的解释VER和MEA-VER对Ag＋的吸附过程.VER和MEA-VER对Ag＋的吸附机理主要有电荷吸附和配位吸附。In this study, raw vermiculite has been modified by 2-aminoethanethiol（MEA） to obtain organo-vermiculite as adsorbent for the removal of silver ions in aqueous solution. The physicochemical properties of the raw and modified vermiculites were analyzed by Fourier transform infrared（FTIR） spectroscopy, thermogravimetry-differential scanning calorimetry（TG-DSC） and BET analysis, which indicated that MEA was successfully grafted onto the vermiculite. Additionally, batch adsorption experiments involving initial p H, adsorbent dosage, time and temperature demonstrated that the adsorption capacity of Ag＋ onto MEA-VER was improved highly compared with that of raw vermiculite. The optimum adsorbent dosage was 2.0g/L, the adsorbents presented a high removal efficiency of Ag＋ in a wide range of initial p H values（6-12）. The kinetics studies showed that the adsorption process was described well with pseudo-second-order model and the equilibrium was achieved at about 200 min of contact time. The adsorption isotherm of Ag＋ onto vermiculites fitted the Langmuir model well. All these results indicated that the adsorption process onto vermiculites was taken place mainly by coordination and electrostatic adsorption.

关 键 词：巯基乙胺 蛭石 Ag+ 吸附 

分 类 号：X52[环境科学与工程—环境工程]