Targeted recovery of metals from thermoelectric generators (TEGs) using chloride brines and ultrasound
Targeted recovery of metals from thermoelectric generators (TEGs) using chloride brines and ultrasound
复制标题
使用氯化物盐水和超声波从热电发电机 (TEG) 中定向回收金属
DOI：
10.1039/d3su00087g
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Zante G
中科院分区：
文献类型：
--
作者：
Zante G
从热电发电机（TEG）中回收元素铜，铋，碲，锑和锡对于回收高含量的关键金属和由于不正确处置TEG而造成的环境污染的潜在风险以及实现循环经济至关重要。在这项工作中，水性氯化胆碱和氯化钙六水合物盐水的特点，并结合使用铜（II）作为氧化剂浸出铜和锡从TEG。这使得Bi 2-xSbxTe 3腿可以通过过滤轻易地与陶瓷衬底分离。结果表明，在低氯化物含量，表面钝化和氧化物种的溶解度是对氧化的限制因素，而溶剂粘度（传质）是在高氯化物含量的限制因素。通过紫外-可见光谱法测定了在不同盐水中形成的铜（II）物种。氧化物种的氧化还原电位被发现显着改变氯化胆碱的含量，但没有这么多的氯化钙六水合物的含量，这表明在不同的盐水中的氯化物活性的变化。所开发的方法已被证明是一种可行且可扩展的方法，可以从含有TEG的电子废物中回收高价值的关键金属。
Recovery of elemental copper, bismuth, tellurium, antimony and tin from thermoelectric generators (TEGs) is vital to recover the high content of critical metals and potential risk of environmental pollution as a result of incorrect disposal of TEGs and to enable the circular economy. In this work, aqueous choline chloride and calcium chloride hexahydrate brines were characterised and used in combination with copper(II) as an oxidising agent to leach copper and tin from TEGs. This permitted the Bi2−xSbxTe3 legs to be readily separated from the ceramic substrates by filtration. It was shown that at low chloride content, surface passivation and solubility of the oxidised species were the limiting factors towards oxidation, whereas solvent viscosity (mass transport) was the limiting factor at high chloride content. The copper(II) species formed in the different brines were determined via UV-vis spectroscopy. The redox potentials of the oxidising species were found to be significantly altered by choline chloride content, but not so much by calcium chloride hexahydrate content, suggesting variation in chloride activity within the different brines. The developed approach has been shown to be a viable and scalable method to recover high value critical metals from e-waste containing TEGs.