酸性H_(2)O_(2)氧化预处理浮选金精矿及其机理研究  

Oxidation Pretreatment of Flotation Gold Concentrate by Acidic H_(2)O_(2) and Its Mechanism Study

作　　者：支永祥 唐云[1,3] 邓政斌 李帅 李宜昌[1] 吴波 ZHI Yongxiang;TANG Yun;DENG Zhengbin;LI Shuai;LI Yichang;WU Bo(Mining College,Guizhou University,Guiyang 550000,China;Guizhou Zijin Mining Co.,Ltd.,Qianxinan 562400,China;Guizhou Key Laboratory of Comprehensive Utilization of Nonmetallic Mineral Resources,Guiyang 550000,China)

机构地区：[1]贵州大学矿业学院,贵州贵阳550000 [2]贵州紫金矿业股份有限公司,贵州黔西南562400 [3]贵州省非金属矿产资源综合利用重点试验室,贵州贵阳550000

出　　处：《金属矿山》2022年第12期98-107,共10页Metal Mine

基　　金：国家自然科学基金项目(编号:51864010);贵州省科技计划项目(编号:黔科合基础[2017]1404);黔科合平台人才项目(编号:[2018]5781)。

摘　　要：酸性H_(2)O_(2)氧化法是一种有效的难选金精矿预处理方法,可以使黄铁矿、毒砂等载金矿物被有效溶解,从而使金暴露出来,提高金浸出率。研究了酸性H_(2)O_(2)体系中黄铁矿的氧化机制,并探究了该系体中温度、矿浆浓度、H_(2)SO_(4)和H_(2)O_(2)浓度等对浮选金精矿的预处理效果。结果表明:H_(2)O_(2)氧化过程中没有固相生成物,黄铁矿中的Fe转化为Fe^(2+)和Fe^(3+)于溶液中,Fe^(2+)与H_(2)O_(2)可发生Fenton反应生成氧化性极强的羟基自由基(·OH);氧化过程中有H_(2)SO_(4)生成,体系的p H值随着反应进行逐渐降低;黄铁矿主要被酸性H_(2)O_(2)、·OH和Fe^(3+)氧化,体系中S最终转化为SO_(4)^(2-)或HSO_(4)^(-)。浮选金精矿在温度为30℃、矿浆浓度为100g/L、H_(2)SO_(4)初始浓度为0.18mol/L和H_(2)O_(2)初始浓度为1.76mol/L的条件下氧化预处理后,Fe浸出率、试样失重率分别为95.33%和51.42%;浮选金精矿直接浸出时金浸出率仅为11.68%,而经过酸性H_(2)O_(2)预处理—浸出后,金浸出率可达92.69%。Acid H_(2)O_(2)oxidation method is an effective pretreatment method for refractory gold concentrate.Pyrite,arsenopyrite and other gold carriers can be effectively dissolved,exposing gold and improving gold leaching rate.Studies the oxidation mechanism of pyrite in acidic H_(2)O_(2)system,and explores the pretreatment effect of temperature,pulp concentration,H_(2)SO_(4)and H_(2)O_(2)concentration in this system on flotation gold concentrate.The results show that there is no solid phase product in the oxidation process of H_(2)O_(2),Fe in pyrite is converted into Fe^(2+)and Fe^(3+)in solution,and Fe^(2+)can react with H_(2)O_(2)to form highly oxidizing hydroxyl radicals(·OH);H_(2)SO_(4)is generated in the oxidation process,and the pH of the system gradually decreases with the reaction;Pyrite is mainly oxidized by acidic H_(2)O_(2),·OH and Fe^(3+),and S in the mineral is finally converted to SO_(4)^(2-)or HSO_(4)^(-).The Fe leaching rate and weight loss rate of flotation gold concentrate after oxidation pretreatment under the optimal conditions of 30℃,100 g/L pulp concentration,0.18 mol/L H_(2)SO_(4)initial concentration and 1.76 mol/L H_(2)O_(2)initial concentration are 95.33%and 51.42%respectively.When the flotation gold concentrate is directly leached,the leaching rate of gold is only 11.68%,after acid H_(2)O_(2)pretreatment leaching,the leaching rate of gold can reach 92.69%.

关 键 词：浮选金精矿 H_(2)O_(2) 氧化预处理 黄铁矿 FENTON反应 

分 类 号：TD926[矿业工程—选矿]