ABSTRACT

To mitigate the trace elements (TE) dispersion in acid mine drainage (AMD), laboratory experiments were carried out comparing nine agricultural by-products. Five adsorbent materials were selected for adsorption batch experiments. Then, the biosorbents were tested to remove TE from AMD collected from oxidized tailings heaps, using equilibrium experiments. The As adsorption on carbonatite was high (15.4 g kg⁻¹); Cd (4.1 g kg⁻¹) on cow manure; Cu (17.9 g kg⁻¹) on carbonatite; Pb (14.1 g kg⁻¹), and Zn (16.4 g kg⁻¹) on rabbit manure. The Zn adsorption on oat straw and carbonatite was well fit by Freundlich isotherm. The Langmuir equation mimics well Zn and Cd adsorption by peat moss and caw manure; Cu adsorption on peat moss and vermicompost. Except for vermicompost and carbonatite, the adsorption improved as the buffer capacity of the biosorbents increased, following a second-order equation. The FTIR analysis showed that the carboxylic, aromatic, and aliphatic aldehyde groups were involved in TE adsorption. Soluble-As, -Cd, -Cu, and -Zn from AMD were removed (90%) by the addition of 4 and 8% (m/v) of sheep manure, cow manure, rabbit manure, vermicompost, and carbonatite. Lead concentration in AMD was increased due to the addition of the biosorbents.

摘要

为了减轻酸性矿山排水 (AMD) 中的微量元素 (TE) 分散，进行了实验室实验，比较了九种农业副产品。选择五种吸附材料进行批量吸附实验。然后，使用平衡实验测试生物吸附剂从从氧化尾矿堆收集的 AMD 中去除 TE。As 在碳酸岩上的吸附很高（15.4 g kg ^-1）；牛粪中的Cd (4.1 g kg ^{-1 )；}Cu (17.9 g kg ^-1 ) 在碳酸盐上；Pb (14.1 g kg ^-1 ) 和 Zn (16.4 g kg ^-1) 在兔粪上。Freundlich等温线很好地拟合了燕麦秸秆和碳酸岩上的Zn吸附。Langmuir 方程很好地模拟了泥炭藓和牛粪对 Zn 和 Cd 的吸附；泥炭藓和蚯蚓堆肥对铜的吸附。除蚯蚓粪和碳酸盐外，吸附随着生物吸附剂缓冲能力的增加而提高，遵循二阶方程。FTIR 分析表明羧基、芳族和脂肪族醛基参与了 TE 的吸附。通过添加 4% 和 8% (m/v) 的羊粪、牛粪、兔粪、蚯蚓粪和碳酸盐，可去除 AMD 中的可溶性砷、-镉、-铜和-锌 (90%)。由于添加了生物吸附剂，AMD 中的铅浓度增加。