Physico Chemical Study on Copper Smelting (I). Measurement of Equilibrium of the Reduction of Solid Copper Sulphides by Hydrogen

Abstract

The authors measured the equilibrium of the reaction, Cu₂S(S)+H₂(g)\ ightleftarrows2Cu(S)+H₂S(g) at the temperature range from 700° to 900° by means of flow method. The equations for the temperature function of the equilibrium constant and Gibbs’ free energy changy in the above reaction from the experimental results were obtained as follows: logK_P=log\fracp_H_2SpH_2=\frac-1214T-1.393
ΔF=5555+6.377T Then, comparing the thermodynamical data of FeS with those of Cu₂S, the authors concluded that the former was unstable at higher temperature range, 930∼1000°C and the lattr at lower temperature range, 700∼930. Furthermore, combining the above equation with the equation of the temperature function of dissociation constant of hydrogen sulphide gas the following equation were obtained: & 4Cu+S_2 \ ightleftarrows2Cu_2S
& logK’=log\frac1p_S_2=\frac14578T-4.896
& ΔF°=-66694+22.399T