Arsenic Separation from Arsenic-Bearing Materials and Preparation of Arsenic Products: Recent Advances

Arsenic is used in compound semiconductors, optoelectronic materials, specialty alloys, and fine chemicals owing to its distinctive chemical and electronic properties. However, arsenic is generated as an associated element in nonferrous-metallurgical and resource-recycling processes, including flue dusts, slags, and aqueous wastes, where its toxicity needs to be properly and safely controlled. This review examines arsenic separation from arsenic-bearing materials and arsenic-product preparation, with emphasis on reaction principles, requirements of raw materials, and the typical processing and preparation techniques. Pyrometallurgical approaches include roasting, vacuum roasting/distillation, reduction smelting, and bath smelting; hydrometallurgical approaches include acidic and alkaline leaching, precipitation-based immobilization, ion exchange, adsorption, and solvent extraction. For complex arsenic-bearing materials, multiple metallurgical methods need to be used for processing. Product-preparation methods are summarized for crude and refined As2O3, metallic arsenic, high-purity arsenic, AsH3, GaAs, InAs, and Zn3As2. Further work is needed to improve separation selectivity, verify the long-term stability of immobilized arsenic, and refine processes for high-purity arsenic production. Recovery should be limited to applications with defined product specifications and justified demand, rather than expanded into low-value uses.