Preparation and adsorption mechanism of rare earth-doped adsorbent for arsenic(V) removal from groundwater

Human poisoning and death from arsenic(As) have occurred as a result of drinking water contaminated with As in some regions and countries, such as Taiwan, Chile, Bangladesh, and In-dia[1]. Chronic arsenism poses a serious health problem in China also[2]. If China lowers its current drinking water standard of As from 0.05 to 0.01 mg/L[3], a level adopted by WHO[4] and some industrialized countries[5], the population affected will increase significantly. It is of great impor-tance to develo…     

用于地下水中砷去除的铈铁复合材料的制备和作用机制

对所研制的几种复合型稀土金属铁氧化物吸附剂对饮用水中砷(V)(As(V))的吸附性能进行比较实验, 结果表明铈复合吸附剂(CFA)的吸附性能较好. 利用X射线衍射(XRD)、表面电荷、红外光谱(IR)和X射线光电子能谱(XPS)等测定手段对CFA的性质和吸附机理进行了初步探讨. 材料的XRD表征表明, 稀土铁氧化物材料制备过程中稀土嵌入晶格起到了对铁氧化物规则晶体的破碎作用;通过酸碱滴定计算出来的CFA的零电荷点(pHzpc)为5.8, 结合IR表征揭示了由于材料的金属氧化物表面羟基作用引起的特性吸附对砷的去除起到的重要作用; XPS则表明少量稀土铈在铁基材料中的复合掺杂嵌入可以提高载体铁氧化物的活性, 从而增强了对砷的去除效果.