Direct Microwave Roasting of Arsenic-Bearing Pyrite Concentrates.

Arsenic-bearing pyrite was used as an indicator to investigate microwave roasting behavior of pyrite concentrates. Appearance of the microwave roasted sample showed that the irradiation-induced transformation started from a small area of the crucible and gradually advanced to the remainder zone. X-ray diffraction (XRD) analysis showed that the arsenic contained in the pyrite was oxidized to As2O3, and that the pyrite was converted into pyrrhotite, hematite, and Fe3O4. The effect of the microwave power, the sample mass, and the microwave irradiation time on the roasting properties was also studied. The results showed that the mass loss ratio increased with the microwave power and the microwave roasting time. [ABSTRACT FROM AUTHOR]