(中南大学 冶金与环境学院，长沙 410083)
摘 要: 考察锌粉置换镓锗渣硫酸浸出中，硫酸浓度、温度、液固比、浸出时间和添加剂对Ga、Ge浸出率及浸出渣过滤性能的影响，揭示添加硝酸钠和十二烷基磺酸钠促进浸出过程的作用机理。结果表明:浸出液中添加适量硝酸钠或十二烷基磺酸钠，均可促进Ga、Ge浸出;此外，十二烷基磺酸钠还可改善浸出渣的过滤性能。添加剂的作用机理为硝酸根能使Ga、Ge单质及其硫化物氧化，从而促进Ga、Ge浸出;十二烷基磺酸钠则通过促进溶液中硅胶的絮凝，减少其对Ga、Ge的吸附，同时，使浸出渣的过滤性能得以改善。在温度为90 ℃、液固比为10 mL/g、搅拌速度为300 r/min、浸出时间为4 h、硫酸浓度为156 g/L、硝酸钠浓度为52.29 g/L、十二烷基磺酸钠浓度为20.5 g/L的条件下，Ga和Ge的浸出率可分别达到97.01%和90.45%，浸出料浆过滤速度由未添加十二烷基磺酸钠时的0.48 mL/min提高到30.65 mL/min。
关键字: 镓;锗;浸出;过滤性能
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:The sulfuric acid leaching of the zinc powder replacement residue containing gallium and germanium was carried out. The effects of sulfuric acid concentration, temperature, liquid-solid ratio, leaching time and additives on the leaching efficiencies of gallium and germanium, together with the filterability of the leaching residues were investigated. The effective mechanisms of improving the leaching through adding sodium nitrate and sodium dodecyl sulfate were found out. The results show that adding both sodium nitrate and sodium dodecyl sulfate can improve the leaching of gallium and germanium. Moreover, adding sodium dodecyl sulfate can also improve the filterability of leaching residues obviously. These could be attributed to the fact that nitrate ions oxidize elemental gallium and germanium, as well as their sulfides, thereby increasing the leaching efficiencies of gallium and germanium, while the sodium dodecyl sulfonate promotes the flocculation of silica gel, thus the absorption of silica on gallium and germanium decreases and the filterability of the leaching residues improves. Leaching the zinc powder replacement residue for 4 h under the conditions of temperature of 90 ℃, liquid-solid ratio of 10 mL/g, stirring rate of 300 r/min, sulfuric acid concentration of 156 g/L, sodium nitrate of 52.29 g/L, sodium dodecyl sulfonate concentration of 20.5 g/L, the leaching rate of gallium and germanium reach 97.01% and 90.45%, respectively. In addition, the filtration rate of the leaching slurry increases from 0.48 mL/min to 30.65 mL/min with the addition dosage of sodium dodecyl sulfonate increasing from 0 to 20.5 g/L.
Key words: gallium; germanium; leaching; filterability
