Study on treatment of ammonia leaching slag in the metallurgical process of tungsten

Abstract

The research of recovering WO₃ from ammonia leaching slag in the extractive process of tungsten has been performed. The results show that the mechanically activated decomposition with Na₂CO₃ for ammonia leaching slag is feasible. After the treatment of ammonia leaching slag containing WO₃ 10%, the content of insoluble WO₃ in residue is 1%–2% and the tungsten recovery is 81%–90% when the total amount of Na₂CO₃ and NaOH is 4 times of their theoretical value and the slag is kept for 2 hours at 190 C. The obtained Na₂WO₄ solution can satisfy the requirements of subsequent production process after purification.

Keywords

ammonia leaching slag / mechanically activated decomposition / sodium carbnate / leaching efficiency