Green City Technology Institute, Korea Institute of Science and Technolgy, Seoul 136-791, South Korea.
Department of Chemistry, Dong-A University, Busan 604-714, South Korea.
J Hazard Mater. 2015 Jul 15;292:146-54. doi: 10.1016/j.jhazmat.2015.03.026. Epub 2015 Mar 17.
Acid mine drainage sludge (AMDS) is a solid waste generated following the neutralization of acid mine drainage (AMD). This material entrapped in calcium alginate was investigated for the sorption of As(III) and As(V). Three different adsorbent materials were prepared: AMDS alginate beads (AABs), goethite alginate beads (GABs), and pure alginate beads. The effects of pH and the adsorption kinetics were investigated, and the adsorption isotherms were also evaluated. The optimum pH range using the AABs was determined to be within 2-10 for As(III) and 2-9 for As(V). Adsorption equilibrium data were evaluated using the Langmuir isotherm model, and the maximum adsorption capacity qmax was 18.25 and 4.97 mg g(-1) for As(III) on AAB and GAB, respectively, and 21.79 and 10.92 mg g(-1) for As(V) on AAB and GAB, respectively. The adsorption of As(III) and As(V) was observed to follow pseudo-second order kinetics. The As K-edge X-ray absorption near-edge structure (XANES) revealed that the adsorbed As(III) on the AABs was oxidized to As(V) via manganese oxide in the AMDS.
酸性矿山排水污泥 (AMD) 是在中和酸性矿山排水 (AMD) 后产生的一种固体废物。本文研究了用钙藻酸盐包埋的 AMD 污泥对 As(III)和 As(V)的吸附作用。制备了三种不同的吸附剂材料：AMD 藻酸盐珠粒 (AABs)、针铁矿藻酸盐珠粒 (GABs) 和纯藻酸盐珠粒。考察了 pH 值和吸附动力学的影响，并评价了吸附等温线。AABs 最适 pH 值范围确定为 As(III)为 2-10，As(V)为 2-9。使用 Langmuir 等温线模型评价吸附平衡数据，AAB 和 GAB 对 As(III)的最大吸附容量 qmax 分别为 18.25 和 4.97mg g(-1)，AAB 和 GAB 对 As(V)的最大吸附容量 qmax 分别为 21.79 和 10.92mg g(-1)。As(III)和 As(V)的吸附符合准二级动力学。As K 边 X 射线吸收近边结构 (XANES) 表明，AABs 上吸附的 As(III)通过 AMD 中的氧化锰被氧化为 As(V)。
