Effect of sodium chloride on sulfur speciation of chalcopyrite bioleached by the extreme thermophile Acidianus manzaensis

► 0.66 g/L sodium chloride promoted the concentration of copper ions from 2.37 g/L to 2.67 g/L in 10 days bioleaching. ► The addition of sodium chloride effectively reduced the accumulation of elemental sulfur. ► The accumulation of elemental sulfur is likely mainly responsible for the slowdown in the dissolution rate.