摘要
The gold dissolution in anoxic cyanide solution in the presence of chalcopyrite was studied with a rotating disc electrode.It was found that the presence of chalcopyrite reduced and enhanced the dissolution activity of pure gold in the low and high potential regions,respectively.The dissolution of gold was diffusion-controlled at low potentials(≤177 mV)and low cyanide concentrations(≤980 mg/L);however,above the cyanide concentration of 980 mg/L,the current density of gold decreased and the dissolution of gold changed from diffusion-control to electrochemical reaction-control.At high potentials(>177 mV),gold dissolution was always controlled by diffusion.In cyanide solution containing chalcopyrite,appropriate increase of pH value and temperature could accelerate the dissolution of gold,but high pH value would promote the generation of passivation,which was harmful for the dissolution of gold in cyanide solution.
利用旋转圆盘电极研究了金在有黄铜矿存在的缺氧氰化物溶液中的阳极溶解特性。研究发现:黄铜矿的存在会削弱金在低电位区的氰化溶解活性,但会增强其在高电位区的溶解活性。在电位≤177m V时,金的溶解过程控制步骤与体系中氰化物浓度有关,当氰化物浓度低于980mg/L时,金的溶解过程受扩散控制;当氰化物浓度高于980mg/L时,金的阳极溶解电流密度降低,溶解过程由扩散控制转变为电化学反应控制。在电位>177 mV时,金的阳极溶解始终受扩散控制,而与体系中氰化钠浓度无关。同时,在含黄铜矿的氰化物溶液中,适当提高体系pH值和升高温度可以促进金阳极溶解,但是pH>11.5也会促进钝化作用的产生而对金的氰化溶解不利。
作者
YANG Wei
ZHANG Kai
WANG Ya-ping
LONG Tao
WAN He
LI Hui
WANG Qian
杨玮;张凯;王亚平;龙涛;宛鹤;李慧;王倩(School of Resources Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Key Laboratory of Gold and Resources in Shaanxi Province,Xi’an 710055,China;School of Foreign Languages,Baoji University of Arts and Sciences,Baoji 721013,China)
基金
Project(51474169)supported by the National Natural Science Foundation of China
Project(18JS061)supported by the Key Laboratory Research Project of Education Department in Shaanxi Province,China。