一种矿山酸性废水利用的新方法:活化高碱石灰溶液中被抑制黄铜矿的浮选

An innovative option for the activation of chalcopyrite flotation depressed in a high alkali solution with the addition of acid mine drainage

硫化铜矿山容易产生富含硫酸、重金属离子的矿山酸性废水,从而对周边生态系统构成威胁。本文研究了矿山酸性废水对高碱石灰溶液中被抑制黄铜矿浮选的活化机制。试验结果表明;当矿山酸性废水与高碱石灰溶液体积比为3:1时,被抑制黄铜矿的浮选回收率提高近12%;矿山酸性废水能够有效解吸原先罩盖在黄铜矿表面的亲水性钙物种,并促使铜离子在矿物表面吸附;黄铜矿表面铜原子浓度增加了2.2%,Ca—O/OH物种的浓度降低了33.24%,S 2p能谱中单一硫化物(S_(2)-)和多硫化物(S_(2)^(2-))的面积占比分别增加了14.67%和23.96%。捕收剂吸附量和微区电化学交流阻抗检测结果显示,经过矿山酸性废水活化后,黄铜矿表面异戊基黄原酸钠的吸附量增加了1.99 mg/g,矿物表面微区电化学交流阻抗值由1.30×10^(5)Ω降低到1.13×10^(5)Ω,黄铜矿表面的疏水性得到明显改善。本论文为矿山酸性废水资源的综合利用和尾矿中硫化铜矿的回收提供了一种新的途径。

Acid mine drainage(AMD)released from copper sulfide contains a large quantity of sulfuric acid and heavy metals,thus being a threat to the surrounding ecosystem.In this study,AMD is used to evaluate options for activation of chalcopyrite depressed by a high alkali solution(HAS).The results showed the flotation recovery of chalcopyrite inhibited by HAS could be increased by~12%with a volume ratio of AMD to HAS of 3:1.AMD promoted desorption of calcium components on chalcopyrite surfaces,and the adsorption of copper ions increased Cu-active sites on the mineral surfaces.Eventually,the copper atomic concentration of chalcopyrite surface increased by 2.2%,and the Ca—O/OH content decreased by 33.24%.Meanwhile,the area ratios of monosulfide(S_(2)−)and disulfide(S_(2)2−)increased by 14.67%and 23.96%.Adsorption and localized electrochemical impedance spectroscopy(LEIS)confirmed that the average impedance of chalcopyrite surface obviously decreased from about 1.30×10^(5)Ωto 1.13×105Ω,and the adsorption amount of sodium isoamylxanthates(SIX)on the chalcopyrite sample increased by 1.99 mg/g.AMD promotes the adsorption of SIX and improves the hydrophobicity of chalcopyrite significantly.This study provided an innovative option for the comprehensive utilization of AMD,as well as the recovery of chalcopyrite from copper sulfide tailings.