锌粉置换镓锗渣草酸浸出过程  

Oxalic acid leaching process of zinc powder replacement residue containing gallium and germanium

作　　者：刘付朋 刘志宏 李玉虎 刘智勇 李启厚 LIU Fu-peng;LIU Zhi-hong;LI Yu-hu;LIU Zhi-yong;LI Qi-hou(School of Metallurgy and Environment, Central South University, Changsha 410083, China)

机构地区：[1]中南大学冶金与环境学院,长沙410083

出　　处：《中国有色金属学报》2017年第10期2154-2163,共10页The Chinese Journal of Nonferrous Metals

基　　金：中国博士后科学基金面上项目(2012M521544)~~

摘　　要：考察锌粉置换镓锗渣草酸浸出过程中,草酸浓度、浸出时间、液固比、浸出温度、双氧水浓度对镓、锗、锌、铁、铜、硅浸出率及浸出料浆过滤性能的影响,揭示在草酸浸出体系下添加双氧水促进镓、锗浸出的作用机理。结果表明,采用草酸和双氧水为浸出剂,不仅可实现镓、锗的选择性浸出,还可显著改善浸出料浆的过滤性能。双氧水促进镓、锗浸出的机理为其作为氧化剂使镓、锗单质及其硫化物氧化为可溶的氧化物;草酸与镓、锗可生成稳定络合物,而与硅的作用较弱,从而促进镓、锗的浸出,同时使浸出渣的过滤性能得以改善。在草酸浓度为110 g/L、双氧水浓度为0.12 mol/L、液固比(L/S)为8、搅拌速度为300 r/min、浸出温度为40℃、浸出时间为30 min的条件下,镓和锗浸出率分别为99.32%、98.86%,而铜、锌、硅的浸出率分别在0.82%、0.84%、0.43%,且浸出料浆的过滤速度由常压硫酸浸出体系下的0.48 mL/min提高到100 mL/min。The oxalic acid leaching of the zinc powder replacement residue containing gallium and germanium was carried out. The effects of oxalic acid concentration, leaching time, liquid-to-solid（L/S） ratio, leaching temperature, and hydrogen peroxide concentration on the leaching of gallium and germanium, together with the filterability of the leaching residues were investigated. The effective mechanisms of improving the leaching through adding hydrogen peroxide in oxalic acid leaching system were found out. The results show that using oxalic acid and hydrogen peroxide as leachant can effectively promote the leaching of Ga and Ge. Moreover, the filterability of leaching residues also can be obviously improved in the oxalic acid leaching system. These could be attributed to the fact that hydrogen peroxide oxidize elemental gallium and germanium, as well as their sulfides, while the oxalic acid promotes the formation of gallium and germanium complex, and oxalic acid has negligible effects on silica, thus the leaching of gallium and germanium and the filterability of the leaching residues were improved. The optimal leaching conditions are as follows： oxalic acid concentration of 110 g/L, hydrogen peroxide concentration of 0.12 mol/L, L/S ratio of 8, temperature of 40 ℃, stirring rate of 300 r/min, and leaching time of 30 min. Under the optimal conditions, 99.32% of Ga and 98.86% of Ge were leached out, while the leaching of Zn, Cu and Si were 0.815%, 0.842% and 0.430%, respectively. Moreover, the filtration rate of the leaching slurry increases from 0.48 mL/min in atmospheric pressure acid leaching system to 100 mL/min.

关 键 词：镓 锗 草酸 双氧水 浸出 

分 类 号：TF803.21[冶金工程—有色金属冶金]