Zinc cyanide removal by precipitation with quaternary ammonium salts
Zinc cyanide removal by precipitation with quaternary ammonium salts
复制标题
季铵盐沉淀法去除氰化锌
DOI：
10.1016/j.seppur.2021.119057
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发表时间：
2021-06-12
影响因子：
8.6
通讯作者：
Barvor, Joshua Bosco
中科院分区：
文献类型：
--
作者：
Liu, Qi;Zhang, Mingqing;Barvor, Joshua Bosco
在黄金加工厂中，通常使用各种氧化方法处理含有金属氰化物物质的最终尾矿，以产生工艺用水的主要来源，其随后再循环到上游单元，例如浮选单元。在一些黄金加工厂中，尽管进行了氰化物销毁过程，但仍有相当数量的金属氰化物物质（如氰化锌）残留在工艺水中。由于残留的氰化锌络合物会抑制金的浮选，因此必须减少工艺用水的量，以使其可以再循环到浮选回路中。根据浮选抑制过程中总氰化物浓度的测定，氰化锌的临界浓度为0.4mmol/L。在本研究中，使用季铵盐沉淀氰化锌络合物的可行性进行了研究，以低于临界浓度。结果表明，在pH = 10的条件下，0.4g/L的十八烷基三甲基溴化铵对60 mg/L的氰化物和50 mg/L的锌（Zn/CN = 1：3）的去除率分别为92.17%和88.86%。残留CN氰化物的浓度小于临界浓度。这表明当非极性有机污染物和适量的盐（
In gold-processing plants, the final tailing containing metal cyanide species is typically treated using various oxidation methods to produce the main source of process water, which is subsequently recycled to the upstream units, such as flotation units. In some gold-processing plants, a considerable amount of metal cyanide species such as zinc cyanide remains in process water, despite the cyanide destruction process. Because residual zinc cyanide complexes can depress gold flotation, the amount of process water must be decreased such that it can be recycled to a flotation circuit. Previous studies report that the critical concentration of zinc cyanide, measured based on the total cyanide concentration during flotation depression, is 0.4 mmol/L. In the present study, the feasibility of using quaternary ammonium salts to precipitate zinc cyanide complexes to less than the critical concentration was studied. The results showed that 92.17% of 60 mg/L of cyanide and 88.86% of 50 mg/L of zinc (molar ratio Zn/CN = 1:3) can be removed using 0.4 g/L of octadecyl trimethyl ammonium bromide at a pH of 10. The concentration of the residual CN cyanide was less than the critical concentration. This indicates that the abovementioned process is effective when nonpolar organic contaminants and moderate amounts of salt (