Abstract:At present, the method of arsenic immobilization in industry is mainly the iron method, that is, the stabilized crystalline FeAsO4 is used for arsenic removal and immobilization. In order to optimize the stability of FeAsO4, inert Fe3O4 was used to coat the FeAsO4 crystals to enhance their acid and alkali resistance and to achieve the purpose of stabilization of arsenic immobilization. The optimum conditions for arsenic immobilization were determined by studying the stability of the composites prepared by different reaction pH value, iron-arsenic molar ratio, and reaction temperatures. Finally, the long-term stability of the magnetic arsenic-immobilization materials in extreme environments was evaluated by toxicity leaching test (TCLP). The experimental results show that the ferric arsenate material stabilized with ferric tetraoxide can meet the relevant national standards for hazardous waste treatment and is a qualified arsenic immobilization material.