State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China.
The Environmental Research Institute, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, 510006, People's Republic of China.
Environ Sci Pollut Res Int. 2018 Jul;25(21):21233-21242. doi: 10.1007/s11356-018-2194-9. Epub 2018 May 19.
To comprehensively reuse the leaching residue obtained from lead-zinc tailings, an active silicon adsorbent (ASA) was prepared from leaching residue and studied as an adsorbent for copper(II), lead(II), zinc(II), and cadmium(II) in this paper. The ASA was prepared by roasting the leaching residue with either a NaCO/residue ratio of 0.6:1 at 700 °C for 1 h or a CaCO/residue ratio of 0.8:1 at 800 °C for 1 h. Under these conditions, the available SiO content of the ASA was more than 20%. The adsorption behaviors of the metal ions onto the ASA were investigated and the Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models were used to analyze the adsorption isotherm. The result showed that the maximum adsorption capacities of copper(II), lead(II), cadmium(II), and zinc(II) calculated by the Langmuir model were 3.40, 2.83, 0.66, and 0.62 mmol g, respectively. The FT-IR spectra of the ASA and the mean free adsorption energies indicated that ion exchange was the mechanism of copper(II), lead(II), and cadmium(II) adsorption and that chemical reaction was the mechanism of zinc(II) adsorption. These results provide a method for reusing the leaching residue obtained from lead-zinc tailings and show that the ASA is an effective adsorbent for heavy metal pollution remediation.
为了全面再利用从铅锌尾矿中得到的浸出残渣，本文制备了一种活性硅吸附剂（ASA），并将其作为一种吸附剂来研究对铜（II）、铅（II）、锌（II）和镉（II）的吸附性能。ASA 是通过在 700°C 下用碳酸钠/残渣比例为 0.6:1 或者在 800°C 下用碳酸钙/残渣比例为 0.8:1 对浸出残渣进行煅烧 1 小时制备得到的。在这些条件下，ASA 的有效 SiO 含量超过 20%。研究了金属离子在 ASA 上的吸附行为，并采用 Langmuir、Freundlich 和 Dubinin-Radushkevich 等温模型来分析吸附等温线。结果表明，Langmuir 模型计算得到的铜（II）、铅（II）、镉（II）和锌（II）的最大吸附容量分别为 3.40、2.83、0.66 和 0.62 mmol·g。ASA 的傅里叶变换红外（FT-IR）光谱和平均自由吸附能表明，离子交换是铜（II）、铅（II）和镉（II）吸附的机制，而化学反应是锌（II）吸附的机制。这些结果为再利用从铅锌尾矿中得到的浸出残渣提供了一种方法，并表明 ASA 是一种有效去除重金属污染的吸附剂。
