The Solubility of Copper and Its Oxides in Supercritical Steam

Abstract

This paper contains a study of the solubility of copper and its oxides in supercritical steam which was undertaken because of difficulties experienced with copper deposition in the high-pressure turbine of the Ohio Power Company’s Philo 6 supercritical steam-generating cycle. This study shows that copper has appreciable solubility in superheated supercritical steam. The extent of solubility is apparently a function of the oxidation state of the metal, with the highest state of oxidation (CuO) showing the greatest solubility. A slightly increased solubility was effected by increasing pH values from ∼7.5 to ∼9.5 with ammonia. It is also shown that copper solubility is principally a function of pressure over the narrow temperature range tested (900–1150 F) probably because this parameter has the greatest effect on specific volume.