(1. 清华大学 核能与新能源技术研究院,北京 100084;
2. 武汉工程大学 湖北省新型反应器绿色化学工艺重点实验室,武汉 430074)
摘 要: 采用粉碎白铜合金废料→酸浸出→N902萃取分离出铜离子→P204萃取分离出锌离子→水相中剩余硫酸镍溶液工艺回收白铜合金废料中的有色金属。经实验得到较优回收工艺条件是将初步机械粉碎的白铜合金投入硫酸溶液中反应,得到浸出液;使用铜特效萃取剂N902首先分离出浸出液中的铜离子。结果表明,萃取剂N902对铜具有较好的选择性。在相比为1:1、pH值为0.57、N902的体积浓度为50%,混合时间为90 s的条件下,铜的萃取率达到99.36%。使用2 mol/L的硫酸进行反萃操作,平衡时间仅为30 s,反萃回收率达到99.68%;使用萃取剂P204萃取分离后续水相溶液中的锌离子,在相比为2׃1、pH值为2.93、P204体积浓度为40%的条件下,混合时间为1 min,经5级萃取后锌离子的萃取率为99.73%,且几乎不萃取水相中的镍,选择性分离效果好。使用1 mol/L的硫酸反萃,经40 s混合后,反萃达平衡,富锌有机相的反萃率为100%。整条工艺完成了铜、镍和锌3种主要离子间的分离,得到硫酸铜、硫酸锌和硫酸镍3种产品。
关键字: 回收;白铜合金;N902;P204;萃取
(1. Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 102201, China;
2. Hubei Key Laboratory Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology,
Wuhan 430073, China)
Abstract: In order to recover nonferrous metals in copper-nickel alloy scrap, a corresponding technology was adopted as follows crushing copper-nickel alloy scrap→leaching the sample with sulfuric acid→extracting copper ion with N902→extracting zinc ion with P204→getting nickelous sulfate solution. Based on the experiments, the operation fators were optimized as follows. At first, the leaching solution is obtained after putting copper-nickel alloy scrap into sulfuric acid solution. Second, extractant N902 is utilized to extract copper in the leaching solution and has good selectivity to copper. The extraction rate of copper can reach 99.36% at the room temperature when the phase ratio, pH value, N902 concentration and mixing time are 1׃1, 0.57, 50% and 90 s, respectively. The stripping rate of copper is 99.68% by using 2 mol/L sulfuric acid solution after 30 s. Finally, the extraction rate of zinc can reach 99.73% at the room temperature by five-stage extraction when the pH value, phase ratio, P204 concentration and mixing time are 2.93, 2׃1, 40% and 60 s, respectively. At the same time, there is no nickel extracted due to the fine selectivity of the extractant. If stripped with 1 mol/L H2SO4, 100% zinc in the organic phase can be stripped during 40 s. All the above results indicate significantly that the copper, nickle and zinc can be separated successfully by this technology and the three products of copper sulfate, zinc sulfate and nickelous sulfate are finally obtained.
Key words: recycling; copper-nickel alloy; N902; P204; solvent extraction