China Nonferrous Metallurgy

This paper introduces the method for extraction of high purity ammonium rhenate product by cyclic enrichment of rhenium in arsenic sulfide slag-leaching of copper separation solution-iron exchange process. In this process, the rhenium content can be enhanced to 1-2wt.% after enrichment treatment of sulfide slag returned to flash smelting for multiple times; the cost of rhenium leaching can be significantly lowered with rhenium-rich sulfide slag leached by copper separation solution obtained from hydrometallurgical leaching of copper anode slime, and the leaching rate of rhenium can be stably controlled above 95%; the adsorbtion/desorption rate of rhenium in iron exchange process can reach above 97%; the overall recovery rate of rhenium in ammonium rhenate crystallization process is 100%, and the purity of ammonium rhenate stably maintained at 99.99% after secondary crystallization. The whole process flow has the advantages of environmentally friendly, extremely low content of heavy metals in waste waster, very low external discharge and easy to be treated. The production practice in recent three years has proved that this process is characterized by simple process, good stability, low operation cost, little waste water drainage and high rhenium recovery efficiency and high purity in comparison with conventional high-pressure oxidative leaching-extraction process, etc.