A method is described for the removal of high arsenic levels from a gold concentrate involving a weakly reducing atmosphere in a rotary pipe furnace. The results showed that 95% of the arsenic in the gold mineral could be removed if roasted for 40 min at a temperature of 650–700°C, with the resulting roasted materials containing less than 1% As. The concentrate also contained a high concentration of S (∼20 wt%) and, under these operating conditions, over 25% of the S was also removed.
