Thermodynamic properties of cuprous sulphide and its mixtures with sodium sulphide

Abstract

Measurements have been made of the equilibria between H2 + H2S + Cu + Cu2S aiid Hz + H2S + Cu + (Cu2S + Na2S) in the temperature range 527" C to 1152" C.The results have been used for calculation of the thermodynamic properties of solid Cu2S and the activities of Cu2S in both solid and liquid solutions containing up to 37 mole % Na2S. The partial molar heats and entropies of solution of Cu2S in the

Determination of the Standard Free Energy of Formation of Cuprous Sulfide at 300°C

“…Thus it follows from Eq. [14] that AF ~ ------277 • 46 cal [16] Moreover, in view of the temperature dependence of the emf of cell (IV) according to Eq. [15], it follows that AF~ 0 at 279~177 4~ Thus the three phase system Cu-Cu2S-PbS is stable below 279~177 4~ whereas the three-phase system Pb-PbS-Cu2S is stable above 279 ~ • 4~…”

Gibbs Energy Modeling of the Cu-S Liquid Phase: Completion of the Thermodynamic Calculation of the Cu-S System

“…Yagihashi [38] has measured the equilibrium between H 2 S/H 2 gas mixtures and sulfur in liquid copper for the temperature range of 1373 K to 1473 K (1100°C to 1200°C) and sulfur content up to 0.92 wt pct. The temperature range from 800 K to 1425 K (527°C to 1152°C) was chosen by Richardson and Antill [39] to bring cuprous sulfide and its mixtures with sodium sulfide into equilibrium with free copper and a gas mixture consisting of hydrogen and hydrogen sulfide. A radiochemical method based on the sulfur isotope S 35 has been used by Alcock [40] for studying high-temperature equilibria involving H 2 S/H 2 gas mixtures.…”

The Measurement of Sulfur Chemical Potential Differences Using a Calcium Fluoride Solid Electrolyte

“…Also shown in Fig. 4 is the line calculated from the data of Richardson and Antill (13) for the Cu-Cu2S equilibrium and of Rosenqvist (17) for the Ag-Ag2S equilibrium. The solid line in Fig.…”

“…2, in which the solid line fits the least squares expression E (mV) ------128.29 + 0.159T (_.+ 5 mV) [8] The uncertainty indicated in brackets is twice the standard deviation of E about the regression line. Emf's calculated using Richardson and Antill's data (13) for the Gibbs energy of formation of Cu2S and Rosenqvist's data (14) for the Gibbs energy of formation of FeS are also shown in Fig. 2.…”