Abstract Under the advocacy of the sustainable development concept, the extraction process and reaction mechanism for arsenic in alkaline solution were studied with the aim of optimizing the alkaline leaching process of high‑arsenic copper smelting ash and promoting the recovery and harmlessness of arsenic. At 25 °C, the extractant methyltrioctylammonium underwent 6–8 conversions of Na2CO3 solution with a concentration fraction of 12%, and the extraction capacity of thioarsenite was increased to 86.91%. Furthermore, at 25 °C, at an O/A ratio of 1:1 and an phase contact time of 7 min, the thioarsenite stripping exceeded 99%, when using 4% H2O2 + saturated Na2CO3 solution as the stripping. Fourier transform infrared spectroscopy, nuclear magnetic spectroscopy, ultraviolet spectroscopy, and other analytical methods were used to determine the mechanism of the extraction process. It was evident from our experiments that the CO32−-type TOMAC and Na2CO3 solutions could be recycled and reused repeatedly. The overall process required simple materials and did not generate liquid waste. The technique involves a short process, with superior cycle performance, low cost, and high efficiency.

中文翻译：

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转化季铵盐在碱性溶液中溶剂萃取硫代亚砷酸盐的研究

摘要 在可持续发展理念的倡导下，为优化高砷铜冶炼灰碱浸出工艺，促进砷的回收无害化，对碱性溶液中砷的提取工艺及反应机理进行了研究。在25°C下，萃取剂甲基三辛基铵在浓度分数为12%的Na2CO3溶液中经历了6-8次转化，硫代亚砷酸盐的萃取能力提高到86.91%。此外，在 25 °C、O/A 比为 1:1 和相接触时间为 7 min 时，当使用 4% H2O2 + 饱和 Na2CO3 溶液作为汽提时，硫代亚砷酸盐汽提率超过 99%。傅里叶变换红外光谱、核磁光谱、紫外光谱、和其他分析方法被用来确定提取过程的机制。从我们的实验中可以明显看出，CO32-型 TOMAC 和 Na2CO3 溶液可以反复回收和重复使用。整个过程需要简单的材料，不会产生液体废物。该技术工艺流程短、循环性能好、成本低、效率高。