Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Universitätsstrasse 16, 8092 Zürich, Switzerland.
Environ Sci Technol. 2012 Jul 3;46(13):7310-7. doi: 10.1021/es204508t. Epub 2012 Jun 21.
The kinetics and efficiencies of arsenite and arsenate removal from water were evaluated using polyaluminum granulates (PAG) with high content of aluminum nanoclusters. PAG was characterized to be meso- and macroporous, with a specific surface area of 35 ± 1 m(2) g(-1). Adsorption experiments were conducted at pH 7.5 in deionized water and synthetic water with composition of As-contaminated groundwater in the Pannonian Basin. As(III) and As(V) sorption was best described by the Freundlich and Langmuir isotherm, respectively, with a maximum As(V) uptake capacity of ~200 μmol g(-1) in synthetic water. While As(III) removal reached equilibrium within 40 h, As(V) was removed almost entirely within 20 h. Micro X-ray fluorescence and electron microscopy revealed that As(III) was distributed uniformly within the grain, whereas As(V) diffused up to 81 μm into PAG. The results imply that As(V) is adsorbed 3 times faster while being transported 10(5) times slower than As(III) in Al hydroxide materials.
采用富含纳米铝簇的聚合氯化铝颗粒（PAG）评估亚砷酸盐和砷酸盐从水中去除的动力学和效率。PAG 的特征是中孔和大孔，比表面积为 35±1 m(2) g(-1)。在 pH 为 7.5 的去离子水和合成水中进行吸附实验，合成水的组成是潘诺尼亚盆地受污染地下水的成分。分别用 Freundlich 和 Langmuir 等温线很好地描述了 As(III)和 As(V)的吸附，在合成水中的最大 As(V)吸附容量约为 200 μmol g(-1)。虽然 As(III)的去除在 40 h 内达到平衡，但 As(V)在 20 h 内几乎完全去除。微 X 射线荧光和电子显微镜显示，As(III)在颗粒内均匀分布，而 As(V)在 PAG 中扩散了 81 μm。结果表明，在氢氧化铝材料中，As(V)的吸附速度比 As(III)快 3 倍，而迁移速度比 As(III)慢 10(5)倍。
