Abstract In this paper, the potential-pH diagrams of Co-Cl-H2O/Co-C-Cl-H2O systems under the temperature of 25°C were drawn through the basic potential-pH principle with a number of thermodynamic data, and the predominant area of Co(OH)2/CoCO3 in the Co-Cl-H2O/Co-C-Cl-H2O systems which existed stably in the agueous solution were obtained. According to the potential-pH diagram of Co-Cl-H2O/Co-C-Cl-H2O systems as well as numerous published reports in the literature, the potential processes and theoretical feasibility for synthesizing Co(OH)2/CoCO3 using soft-chemical method in agueous solution and recovering valuable metals from the waste lithium-ion batteries by hydrometallurgical method were discussed. The potential-pH diagram of Co-Cl-H2O/Co-C-Cl-H2O systems provided the theoretical foundation for synthesizing Co(OH)2/CoCO3 using electrochemical method in agueous solution and recovering valuable metals by hydrometallurgical method. Hence, high-purity, high-crystallinity submicron Co(OH)2/CoCO3 powder is electro-synthesized through one-step simple deposition procedure. Simultaneously,the influencing factors of dynamics also be discussed. Based on the Stern model, we briefly described the electric double layer model near the electrode in this experiment.

中文翻译：

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氢氧化钴和碳酸钴的制备与回收研究

摘要 本文根据基本的电位-pH原理，结合多项热力学数据，绘制了Co-Cl-H2O/Co-C-Cl-H2O体系在25°C温度下的电位-pH图。得到了稳定存在于水溶液中的 Co-Cl-H2O/Co-C-Cl-H2O 体系中 Co(OH)2/CoCO3 的主要区域。根据 Co-Cl-H2O/Co-C-Cl-H2O 系统的电位-pH 图以及大量已发表的文献报道，利用软水法合成 Co(OH)2/CoCO3 的潜在过程和理论可行性。讨论了水溶液中的化学法和湿法冶金法从废旧锂离子电池中回收有价金属的方法。Co-Cl-H2O/Co-C-Cl-H2O体系的电位-pH图为在水溶液中电化学法合成Co(OH)2/CoCO3和湿法冶金法回收有价金属提供了理论基础。因此，高纯度、高结晶度的亚微米 Co(OH)2/CoCO3 粉末是通过一步简单的沉积过程电合成的。同时还讨论了动力学的影响因素。基于Stern模型，我们简要描述了本实验中电极附近的双电层模型。