Study on thermodynamic model of arsenic removal from oxidative acid leaching

In this paper, we propose a new strategy to remove arsenic from arsenic-containing waste residues by oxidation-acid leaching. The experimental results show the example is effective for different types of arsenic-containing waste residues. Chemical thermodynamic calculations provide guidance for leaching of oxidizing acids, while theoretical calculations and experimental data have successfully proven the shielding layer of AsH3. The acid leaching characteristics of different types of arsenate were analyzed, a multi-metal ion equilibrium system in acid leaching was established, and a model of arsenic removal by oxidizing acid was established. An in-depth understanding of the relationship between the amount of acid required to leaching different arsenic-containing waste residues and the pH of the leachate provides new perspectives on how to efficiently collect hazardous materials from industrial waste residues. (C) 2020 The Authors. Published by Elsevier B.V.