Preparation of High-Purity Arsenic via Hydrogen Reduction of Arsenic Trichloride

摘要

The chemical equilibria involved in the hydrogen reduction of arsenic trichloride under reaction conditions of practical interest are assessed by thermodynamic modeling. Experimental data for high-purity arsenic trichloride are used to optimize the reduction conditions. The optimal residence time of the gas mixture in the reaction zone is 30-50 s. The optimal reduction temperature is 1023 K. Condensation temperatures in the range 600-650 K make it possible to minimize the percentage of amorphous arsenic. The yield of elemental arsenic is approx= 99.99%.