Department of Civil Engineering, North Dakota State University, Fargo, ND 58105, USA; School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China.
Department of Civil Engineering, North Dakota State University, Fargo, ND 58105, USA.
J Hazard Mater. 2010 Dec 15;184(1-3):515-522. doi: 10.1016/j.jhazmat.2010.08.066. Epub 2010 Aug 26.
Granular activated carbon (GAC) was impregnated with iron through a new multi-step procedure using ferrous chloride as the precursor for removing arsenic from drinking water. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analysis demonstrated that the impregnated iron was distributed evenly on the internal surface of the GAC. Impregnated iron formed nano-size particles, and existed in both crystalline (akaganeite) and amorphous iron forms. Iron-impregnated GACs (Fe-GACs) were treated with sodium hydroxide to stabilize iron in GAC and impregnated iron was found very stable at the common pH range in water treatments. Synthetic arsenate-contaminated drinking water was used in isotherm tests to evaluate arsenic adsorption capacities and iron use efficiencies of Fe-GACs with iron contents ranging from 1.64% to 12.13% (by weight). Nonlinear regression was used to obtain unbiased estimates of Langmuir model parameters. The arsenic adsorption capacity of Fe-GAC increased significantly with impregnated iron up to 4.22% and then decreased with more impregnated iron. Fe-GACs synthesized in this study exhibited higher affinity for arsenate as compared with references in literature and shows great potential for real implementations.
颗粒状活性炭 (GAC) 通过使用氯化亚铁作为前驱体的新多步程序进行铁浸渍，以从饮用水中去除砷。扫描电子显微镜 (SEM) 和能谱 (EDS) 分析表明，浸渍的铁均匀分布在 GAC 的内表面上。浸渍的铁形成纳米级颗粒，存在结晶 (纤铁矿) 和非晶态铁两种形式。用氢氧化钠处理铁浸渍的 GAC（Fe-GAC）以稳定 GAC 中的铁，发现浸渍铁在水处理中常见的 pH 范围内非常稳定。使用合成的含砷酸盐污染的饮用水进行等温测试，以评估铁含量为 1.64%至 12.13%（按重量计）的 Fe-GAC 的砷吸附容量和铁利用率。使用非线性回归获得朗缪尔模型参数的无偏估计。随着浸渍铁含量增加到 4.22%，Fe-GAC 的砷吸附容量显著增加，然后随着更多浸渍铁的增加而降低。与文献中的参考文献相比，本研究合成的 Fe-GAC 对砷酸盐表现出更高的亲和力，具有很大的实际应用潜力。
