超声活化过硫酸盐预处理复杂金矿工艺及机理分析  

Process and mechanism analysis of ultrasound-activated persulfate pretreatment of complex gold ores

作　　者：肖毕高 曾国礼 兰国辉 马绍斌 XIAO Bigao;ZENG Guoli;LAN Guohui;MA Shaobin(Yunnan Chihong Zinc Germanium Co.,Ltd.,Huize 654200,China)

机构地区：[1]云南驰宏锌锗股份有限公司,云南会泽654200

出　　处：《中国有色冶金》2025年第1期69-75,共7页China Nonferrous Metallurgy

摘　　要：复杂金矿难处理的一个主要原因是矿物中黄铁矿包裹微细颗粒金,无法使金浸出。传统的氰化法无法有效打开黄铁矿,不能有效利用金资源。为提高复杂金矿的金浸出率,本研究基于过硫酸盐的优异氧化性能及超声波的空化效应,对复杂难处理金矿进行了预氧化处理试验,考察了工艺参数对金矿氧化及浸出效果的影响,并结合表征结果分析了预氧化机理,得到以下主要结论。氧化预处理较佳条件为超声功率480 W、过硫酸钠浓度180 g/L、液固比5∶1、搅拌速率600 r/min、pH=2、预处理时间3 h,在该条件下,金浸出率可达86.97%;在超声活化作用下,过硫酸盐可以释放大量的·OH和SO_(4)^·(-)自由基,这是复杂金矿中硫化物得以有效氧化的关键,另外超声空化作用可有效打开黄铁矿对金的包裹、提高反应物颗粒的比表面积、改变复杂金矿的微观结构,从而大幅提高金浸出率。该技术使得复杂金矿的金浸出率由49.12%提高到86.97%,效果显著,对我国复杂金矿的高效利用及超声应用领域的拓展具有重要意义。One of the main reasons for the difficulty in treating complex gold ores is the presence of fine gold particles encapsulated within pyrite,which prevents the gold from being leached out.Traditional cyanidation methods cannot effectively break down pyrite,leading to inefficient utilization of gold resources.To improve the gold leaching rate of complex gold ores,this study conducted pre-oxidation treatment experiments based on the excellent oxidation performance of persulfates and the cavitation effect of ultrasound.The effects of process parameters on the oxidation and leaching of gold ores were investigated,and the pre-oxidation mechanism was analyzed in conjunction with characterization results,leading to the following main conclusions.The optimal conditions for oxidative pretreatment were an ultrasonic power of 480 W,a sodium persulfate concentration of 180 g/L,a liquid-to-solid ratio of 5∶1,a stirring rate of 600 r/min,pH=2,and a pretreatment time of 3 hours.Under these conditions,the gold leaching rate could reach 86.97%.With the activation of ultrasound,persulfates can release a large number of ·OH and SO_(4)^·(-) radicals,which are key to the effective oxidation of sulfides in complex gold ores.Additionally,the cavitation effect of ultrasound can effectively open up the encapsulation of gold by pyrite,increase the specific surface area of the reactant particles,and change the microstructure of complex gold ores,thereby significantly improving the gold leaching rate.This technology increases the gold leaching rate from 49.12% to 86.97%,with significant effects,and is of great importance for the efficient utilization of complex gold ores in China and the expansion of the application field of ultrasound.

关 键 词：复杂金矿 金浸出率 黄铁矿 预氧化技术 过硫酸盐 超声波技术 空化效应 

分 类 号：TF831[冶金工程—有色金属冶金] TF803.7