Herein, an environmentally friendly and selective leaching process of Cd, from spent Ni-Cd battery, is reported by the use of alkaline glycine solution. The pertinent parameters affecting Cd leaching levels, including the concentration of glycine (0.5-1.5 mol/L), pH (8-11), temperature (25-75 ℃), and time (30-150 min) were statistically investigated via response surface methodology coupled with central composite design. The results showed that the level of Ni in the leaching solution is negligible, especially at the leaching time shorter than 150 min, while Cd leaching percentage can reach higher than 80%, confirming the selectivity of the process. In addition, glycine concentration and time are the most significant parameters, and for achieving a Cd leaching percentage higher than 80%, the level of glycine should be at least 1 mol/L. It was attempted to understand the statistically significant interactions among the factors affecting the Cd leaching process based on a comprehensive thermodynamic discussion. Finally, Cd was successfully precipitated in the form of CdS nanoparticles (∼20 nm) by the addition of Na₂S solution into the obtained leaching solution.

在此，通过使用碱性甘氨酸溶液，报道了从废Ni-Cd电池中对Cd的环境友好和选择性浸出过程。通过反应，统计地研究了影响Cd浸出水平的相关参数，包括甘氨酸浓度（0.5-1.5 mol / L），pH值（8-11），温度（25-75℃）和时间（30-150分钟）。表面方法与中心复合设计相结合。结果表明，浸出液中的镍含量可以忽略不计，特别是浸出时间小于150min时，镉的浸出率可以达到80％以上，从而证明了工艺的选择性。此外，甘氨酸的浓度和时间是最重要的参数，为了使Cd的浸出率高于80％，甘氨酸的含量应至少为1 mol / L。在全面的热力学讨论的基础上，试图了解影响Cd浸出过程的因素之间的统计学显着相互作用。最后，通过添加Na，Cd以CdS纳米颗粒（〜20 nm）的形式成功沉淀。_将2 S溶液注入所得浸出溶液中。