Chaminda G G T, Nakajima F, Furumai H
Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan.
Water Sci Technol. 2008;58(6):1207-13. doi: 10.2166/wst.2008.480.
The size distributions of zinc and copper species in the effluent of a wastewater treatment plant were determined by a combination of ultrafiltration and chelating disk cartridge fractionation. The results showed that 75-87% of total Zn and 84-86% of total Cu were strongly complexed or particle-bound in the final effluents. It was also found that the major part of Cu was bound to ligands in the < 500 Da fraction while the trend for Zn was not so clear and exhibited significant seasonal variability. Labile Cu and Zn were detected not only in the smallest fraction (< 500 Da) but also in the larger fractions. It meant that the labile species in the effluent were not equivalent to free metal ions. Conditional stability constants and ligand concentrations were also determined from the measured metal concentrations by square wave anodic stripping voltammetry. Existence of two types of ligand for each metal was inferred from the experimental data. Conditional stability constant obtained for the stronger type Ligand of Zn was higher than that of Cu, although the estimated Ligand concentrations were almost similar.
通过超滤和螯合盘式柱分离相结合的方法，测定了污水处理厂出水中锌和铜物种的尺寸分布。结果表明，最终出水中75 - 87%的总锌和84 - 86%的总铜以强络合或颗粒结合的形式存在。还发现，大部分铜与<500 Da组分中的配体结合，而锌的趋势不那么明显，且表现出显著的季节性变化。不稳定的铜和锌不仅在最小的组分（<500 Da）中被检测到，在较大的组分中也被检测到。这意味着出水中的不稳定物种并不等同于游离金属离子。还通过方波阳极溶出伏安法根据测得的金属浓度确定了条件稳定常数和配体浓度。从实验数据推断出每种金属存在两种类型的配体。锌的较强类型配体的条件稳定常数高于铜，尽管估计的配体浓度几乎相似。
