Department of Rural Systems Engineering, Seoul National University, Seoul 151-921, Republic of Korea.
J Environ Sci (China). 2012;24(4):589-95. doi: 10.1016/s1001-0742(11)60786-9.
The removal of As(III) and As(V) from aqueous solution was investigated using waste cast iron, which is a byproduct of the iron casting process in foundries. Two types of waste cast iron were used in the experiment: grind precipitate dust (GPD) and cast iron shot (CIS). The X-ray diffraction analysis indicated the presence of Feo on GPD and CIS. Batch experiments were performed under different concentrations of As(III) and As(V) and at various initial pH levels. Results showed that waste cast iron was effective in the removal of arsenic. The adsorption isotherm study indicated that the Langmuir isotherm was better than the Freundlich isotherm at describing the experimental result. In the adsorption of both As(IH) and As(V), the adsorption capacity of GPD was greater than CIS, mainly due to the fact that GPD had higher surface area and weight percent of Fe than CIS. Results also indicated the removal of As(III) and As(V) by GPD and CIS was influenced by the initial solution pH, generally decreasing with increasing pH from 3.0 to 10.5. In addition, both GPD and CIS were more effective at the removal of As(III) than As(V) under given experimental conditions. This study demonstrates that waste cast iron has potential as a reactive material to treat wastewater and groundwater containing arsenic.
采用铸造厂铁铸造过程中的副产品废铸铁研究了从水溶液中去除砷（III）和砷（V）。实验中使用了两种类型的废铸铁：磨料沉淀粉尘（GPD）和铸铁丸（CIS）。X 射线衍射分析表明 GPD 和 CIS 中存在 Feo。在不同砷（III）和砷（V）浓度和不同初始 pH 值下进行了批量实验。结果表明，废铸铁对砷的去除是有效的。吸附等温线研究表明，Langmuir 等温线比 Freundlich 等温线更能描述实验结果。在吸附砷（III）和砷（V）时，GPD 的吸附容量大于 CIS，这主要是因为 GPD 的表面积和铁的重量百分比高于 CIS。结果还表明，GPD 和 CIS 对砷（III）和砷（V）的去除受初始溶液 pH 值的影响，通常从 3.0 到 10.5 时随着 pH 值的增加而降低。此外，在给定的实验条件下，GPD 和 CIS 对砷（III）的去除均优于砷（V）。本研究表明，废铸铁作为一种反应性材料，具有处理含砷废水和地下水的潜力。
