(中南大学 冶金与环境学院，长沙 410083)
摘 要: 针对现行的湿法炼锌渣中萃取镓工艺存在调酸复杂、添加络合剂成本高、有机相损失严重等弊端，采用新型萃取剂HBL121 从锌置换渣的高浓度硫酸浸出液中直接萃取镓，考察料液酸度、萃取剂浓度、萃取温度、萃取时间和相比对萃取的影响以及H2SO4 浓度、反萃温度、反萃时间和反萃相比对反萃的影响，分别绘制萃取平衡等温线和反萃平衡等温线，并对萃取剂转型条件进行研究。结果表明：以有机相组成为40%HBL121(质量分数)+20%癸醇(体积分数)+磺化煤油作为萃取剂，料液酸度为108.67 g/L H2SO4，其最佳萃取条件为萃取温度25 ℃、萃取时间10 min、相比O/A=1:1，经过4 级逆流萃取，镓萃取率达到98.14%。负载有机相用200 g/L 的H2SO4 溶液可选择性反萃镓，得到高纯度硫酸镓溶液，其最佳反萃条件为反萃温度25 ℃、反萃时间8 min、相比O/A=4:1。经过5 级逆流反萃，反萃率可达到99.18%。反萃镓后负载有机相再用7 mol/L 盐酸溶液反萃共萃的铁并转型，控制反萃温度25 ℃、反萃时间2 min、O/A=1.5:1，经过3 级逆流反萃，铁反萃率可达到99.23%并完成转型，萃取剂循环使用。
关键字: 镓；HBL121 萃取剂；锌置换渣；高浓度硫酸浸出液；萃取；反萃
（School of Metallurgy and Environment,Central South University,Changsha 410083,China）
Abstract:The extraction of gallium from high sulfuric acid leach solution of zinc replacing slag by a new extractant HBL121 was carried out based on the problems in the existing extracting process of gallium from zinc smelting slag in hydrometallurgy,such as complex acidity adjusting step,high complexing agent cost,and serious organic phase loss. The effects of feed acidity,extractant concentration,extraction temperature,extraction time and extraction phase ratio on the extraction,and the effects of H2SO4 concentration,stripping temperature,stripping time and stripping phase ratio on the stripping of gallium were investigated. The isotherms of the extraction and stripping were plotted,and the conditions of extractant transformation were researched. The results show that with 40% HBL121 (mass fraction) and 20%(volume fraction) in sulphonated kerosene as extractant,the extraction rate of gallium from the solution with 108.67 g/L H2SO4 reaches 98.14% in four-stage counter current extraction with O/A ratio of 1:1 at 25 ℃ for 10 min. Gallium in loaded organic phase can be selectively stripped using 200 g/L H2SO4 solution and the stripping rate reaches 99.18% in five-stage counter current stripping with O/A ratio of 4:1 at 25 ℃ for 8 min. After gallium stripping,the iron in loaded organic phase can be stripped using 7 mol/L HCl solution and the stripping rate of iron reaches 99.23% in three-stage counter current stripping with O/A ratio of 1.5:1 at 25 ℃ for 2 min. The extractant returns to extraction circularly.
Key words: gallium; HBL121 extractant; zinc replacing slag; high concentration sulfuric acid leaching liquor; extraction; Stripping
