Pretreatment of refractory gold ore by curing with
Materials and reagents All the reagents used in the experiment such as sulfuric acid H 2 SO 4 nitric acid HNO 3 copper sulfate CuSO 4 sodium thiosulfate Na 2 S 2 SO 3 and sodium hydroxide NaOH were analytically pure and the water used in the whole experiment was deionized water with the electrical resistivity of MΩ The refractory