氰化体系中典型硫化物的溶液化学计算及热力学分析  

Solution Chemical Calculation and Thermodynamic Analysis of Typical Sulfides in Cyanide Process

作　　者：张裕海 赵前飞 张剑廷 李慧 陈建福 李俊鹏 郑冰清 ZHANG Yuhai;ZHAO Qianfei;ZHANG Jianting;LI Hui;CHEN Jianfu;LI Junpeng;ZHENG Bingqing(Shanghai Milestone Engineering Co.,Ltd.,Yangzhou 225119,Jiangsu,China;Liaoning Dongda Mining&Metallurgy Engineering Technology Co.,Ltd.,Chaoyang 122000,Liaoning,China;School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,China;Jiangxi Sanhe Gold Industry Co.,Ltd.,Shangrao 334300,Jiangxi,China)

机构地区：[1]上海逢石工程技术有限公司,江苏扬州225119 [2]辽宁东大矿冶工程技术有限公司,辽宁朝阳122000 [3]东北大学资源与土木工程学院,沈阳110819 [4]江西三和金业有限公司,江西上饶334300

出　　处：《有色金属(选矿部分)》2025年第3期42-51,共10页Nonferrous Metals(Mineral Processing Section)

基　　金：国家自然科学基金资助项目(52274256);中央高校基本科研业务专项资金资助项目(N2401023);东北大学博士后基金资助项目(20240206);上饶市揭榜挂帅项目(2021A003);东北大学资源与土木工程学院优秀博士后资助计划项目(20240102)。

摘　　要：氰化法依旧是目前黄金矿山提金系统的主流方法,金精矿中所包含的伴生硫化物在氰化浸出过程中会溶解产生Cu^(2+)、Cu^(+)、Fe^(3+)、Fe^(2+)、Pb^(2+)、Zn^(2+)和S^(2-)等离子,这些离子与氰化药剂作用后的产物在一定程度上不仅破坏了环境,同时还影响了金精矿氰化尾渣中可回收硫化物的浮选指标。因此,利用溶液化学和热力学方法探究了氰化体系中主要的化学组成及其形成条件,以期为后续金精矿氰化尾渣的无害化处置及综合利用提供理论指导。首先,通过溶液化学计算对比分析了不同金属离子与CN^(-)结合形成的配合物的分布分数与CN^(-)浓度的关系,发现在CN^(-)浓度为0.01%~0.10%时,氰化提金系统主要的金属-氰配合物包括Cu(CN)_(3)^(2-)、Cu(CN)_(4)^(_(3)^(-))、Fe(CN)_(6)^(3-)、Fe(CN)_(6)^(4-)、Pb(CN)_(4)^(2-)、Zn(CN)_(4)^(2-)和Zn(CN)_(3)^(-),并随着CN^(-)浓度的改变相互转化。其次,绘制了黄铜矿、黄铁矿、方铅矿和闪锌矿在NaCN^(-)H_(2)O系下的Eh-pH图,并计算获得了典型金属-氰配合物的条件稳定常数,从热力学角度探讨了氰化物对金精矿氰化尾渣中硫化物浮选回收的抑制机理。结果表明,当矿浆pH为10.5~11.5时,Cu(CN)_(2)^(-)、Fe(CN)_(6)^(4-)、Fe(CN)_(6)^(3-)、Zn(CN)_(2)、Zn(CN)_(3)^(-)、CNO^(-)和SCN^(-)能稳定存在于氰化系统中,并缩减了黄铜矿、黄铁矿和闪锌矿的稳定区域。条件稳定常数计算结果表明,高电位、低pH条件下,Fe(CN)_(6)^(4-)、CNO^(-)和SCN^(-)难以被降解,这可能是导致金精矿氰化尾渣中硫化物浮选回收率不高的主要原因。The cyanide method remains the predominant approach for gold extraction in mining operations.During cyanide leaching,sulfide minerals associated with gold concentrates dissolve,releasing metal ions such as Cu^(2+),Cu^(+),Fe^(3+),Fe^(2+),Pb^(2+),Zn^(2+)and S^(2-).Byproducts resulting from these ions'interaction with cyanide reagents harm the environment and reduce the flotation efficiency of recoverable sulfide minerals in cyanide tailings.Thus,the chemical composition and formation conditions of the cyanide system were investigated using solution chemistry and thermodynamics,aiming to guide the safe disposal and comprehensive utilization of gold concentrate cyanide tailings.Firstly,the distribution of metal-cyanide complexes was analyzed in relation to CN^(-)concentration using solution chemistry calculations.Metal-cyanide complexes like Cu(CN)_(3)^(2-),Cu(CN)_(4)^(_(3)^(-)),Fe(CN)_(6)^(3-),Fe(CN)_(6)^(4-),Pb(CN)_(4)^(2-),Zn(CN)_(4)^(2-)and Zn(CN)_(3)^(-)dominate the cyanide gold extraction system at CN^(-)concentrations of 0.01%to 0.10%,interconverting as CN^(-)concentration varies.Secondly,Eh-pH diagrams for chalcoprite,pyrite,galena,and sphalerite in the NaCN^(-)H_(2)O system were constructed,and conditional stability constants of metal-cyanide complexes were determined.The thermodynamic mechanism of cyanide inhibition on sulfide recovery from gold concentrate cyanide tailings was analyzed.The results show that Cu(CN)_(2)^(-),Fe(CN)_(6)^(4-),Fe(CN)_(6)^(3-),Zn(CN)_(2),Zn(CN)_(3)^(-),CNO^(-)and SCN^(-)can stably exist in the cyanide process at pH 10.5-11.5,while stable regions for chalcopyrite,pyrite,and sphalerite are diminished.The results of conditional stability constants show that Fe(CN)_(6)^(4-),CNO^(-)and SCN^(-)are resistant to degradation under high potential and low pH conditions,potentially explaining the low sulfide flotation recovery in gold concentrate cyanide tailings.

关 键 词：氰化浸出 溶液化学 热力学 物种形态 条件稳定常数 

分 类 号：TD952[矿业工程—选矿] TD923