Chapter 12 - Partitioning of electrolytes to steam and their solubilities in steam

Abstract

The applications of partitioning of electrolytes from aqueous solutions to the coexisting steam phase and their ultimate solubility include prediction of the fate of chemical wastes in supercritical water oxidation (SCWO) technologies, the transport and deposition of treatment chemicals and contaminants in the water–steam cycles of fossil-fired and nuclear power plants, the generation of corrosive steam from natural hydrothermal systems, and to the release steam containing a wide range of solutes at extreme conditions associated with volcanoes and volcanic hydrothermal systems. Classical measurements based on solubility and conductivity methods, more recent mass spectrometric observations, have been carried out on a very limited number of systems, and the interpretation of these results is often ambiguous. Direct volatility and solubility measurements must overcome problems, such as pro-grade solubility with temperature and pressure, hydrolysis, effects by corrosive solutes on the experimental containment walls, the attainment of true thermodynamic equilibrium, complete separation of two-phase systems, and analytical challenges when dealing with highly insoluble materials. The chapter provides examples of partitioning: Hydrochloric Acid Partitioning and Sodium Hydroxide Partitioning. The speciation of solutes in both phases, for many systems, is the most important consideration in determining the volatility of most electrolytes.