Sustainable, cost-effective cobalt/nickel separations chemistry contributes to the realization of economically competitive lithium-ion battery recycling, as well as primary mining of cobalt and nickel. Such improvements can address supply chain challenges for cobalt, a critical element. Herein, we disclose a simple method for separating Co/Ni by second coordination-sphere molecular recognition. Selective cobalt precipitation is achieved using carbonate ions in an ammonia solution due to the outer-sphere, hydrogen bonding interactions between [Co(NH₃)₆]³⁺ and CO₃²⁻, evaluated with density functional theory calculations. We demonstrate this method on mixtures of Co/Ni chlorides comprising a 10-fold excess of Ni and provide comparisons with ore-processing systems. High purities (99.4(3)% Co; 98.2(4)% Ni) and recoveries (77(8)% Co; ∼100% Ni) were observed for both Co- and Ni-enriched products using optimized conditions. This method is potentially economically competitive based on initial techno-economic analysis (TEA) and life-cycle assessment (LCA) that also illustrate advantages in terms of sustainability.

中文翻译：

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通过技术经济分析和生命周期评估进行验证的可持续钴分离


可持续、经济高效的钴/镍分离化学有助于实现具有经济竞争力的锂离子电池回收，以及钴和镍的初级开采。这些改进可以解决钴这一关键元素的供应链挑战。在此，我们公开了一种通过第二配位球分子识别分离 Co/Ni 的简单方法。由于 [Co（NH₃）₆]³⁺ 和 CO₃²⁻ 之间的外球氢键相互作用，使用氨溶液中的碳酸根离子实现选择性钴沉淀，通过密度泛函理论计算进行评估。我们在含有 10 倍过量 Ni 的 Co/Ni 氯化物混合物上演示了这种方法，并与矿石加工系统进行了比较。使用优化条件，富钴和富镍产品均具有高纯度（99.4（3）% Co;98.2（4）% Ni）和回收率（77（8）% Co;∼100% Ni）。基于初始技术经济分析 （TEA） 和生命周期评估 （LCA），这种方法在经济上具有潜在竞争力，这也说明了可持续性方面的优势。