Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
J Environ Sci (China). 2009;21(11):1473-9. doi: 10.1016/s1001-0742(08)62442-0.
A novel adsorbent (AMPS-silica) was synthesized by bounding AMPS (2-acrylamido-2-methylpropanesulfonic acid) onto silica surface, which functioned with y-methacryloxypropyltrimethoxysilane reagent. The adsorbent was characterized by nitrogen adsorption/desorption measurement, thermogravimetric analysis (TGA) and potentiometric titration analysis. The TGA result indicated that the surface modification reactions introduced some organic functional groups onto the surface of silica. The surface area of AMPS-silica was 389.7 m2/g. The adsorbent was examined for copper ion removal in series of batch adsorption experiments. Results showed that the adsorption of Cu2+ onto AMPS-silica was pH dependent, and the adsorption capacity increased with increasing pH from 2 to 6. The adsorption kinetics showed that Cu2+ adsorption was fast and the data fitted well with a pseudo second- order kinetic model. The adsorption of Cu2+ onto AMPS-silica obeyed both Freundlich and Langmuir isotherms, with r2 = 0.993 and r2 = 0.984, respectively. The maximum Cu2+ adsorption capacity was 19.9 mg/g. The involved mechanism might be the adsorption through metal binding with organic functional groups such as carboxyl, amino and sulfonic groups. Cu2+ loaded on AMPS-silica could be desorbed in HNO3 solution, and the adsorption properties remain stable after three adsorption-desorption cycles.
一种新型吸附剂（AMPS-二氧化硅）通过将 AMPS（2-丙烯酰胺基-2-甲基丙磺酸）键合到二氧化硅表面上合成，该表面与 y-甲基丙烯酰氧基丙基三甲氧基硅烷试剂结合使用。通过氮气吸附/解吸测量、热重分析（TGA）和电位滴定分析对吸附剂进行了表征。TGA 结果表明，表面改性反应在二氧化硅表面引入了一些有机官能团。AMPS-二氧化硅的比表面积为 389.7 m2/g。在一系列批处理吸附实验中，考察了该吸附剂对铜离子的去除效果。结果表明，Cu2+的吸附与 pH 有关，当 pH 值从 2 增加到 6 时，吸附容量增加。吸附动力学表明 Cu2+的吸附速度很快，数据拟合良好的拟二级动力学模型。Cu2+在 AMPS-二氧化硅上的吸附同时符合 Freundlich 和 Langmuir 等温线，相关系数 r2 分别为 0.993 和 0.984。Cu2+的最大吸附容量为 19.9 mg/g。涉及的机制可能是通过金属与羧基、氨基和磺酸基等有机官能团的配位作用进行吸附。负载在 AMPS-二氧化硅上的 Cu2+可以用 HNO3 溶液解吸，且在三次吸附-解吸循环后，吸附性能保持稳定。
