The Effect of  SO 3 Gas on the Surface Tension of Molten Na2 SO 4

Abstract

12O0~The solubilities of the dopant sulfides are relatively large (15-30 m/o at 1200~ depending on dopant), in agreement with results of Flahaut et aL (4). The much smaller apparent solubilities of Worrell et al. (1) are probably the result of oxygen contamination and formation of rare-earth oxysulfides. Variation of lattice parameter of the CaS solid solution indicates an increase in size of the dopant ion over theoretical predictions based on ion sizes in the pure sulfides. The x-ray pattern of ~-CaY2S4 has been determined, and shows a monoclinic structure which represents a small distortion of the low temperature orthorhombic phase. ABSTRACTThe surface tension of molten Na2SO4 has been me'asured as a function of the partial pressure of SOs gas in equilibrium with the melt (10 -9 ~ Pso3 10 -I atm) over the temperature range of 1175-1400 K. The surface tension, 9 , is independent of Psos over the range of partial pressures employed. The temperature dependence of r is given by --2.568 X 10 -I --6.05 X 10-ST where r has units of N/m and T }s the absolute temperature. The density of Na2SO4 is independent of Pso3 for 10 -9 "~ Pso3 ~ 10-i atm at 1200 and 1250 K, thereby confirming that Na2SO4 is virtually stoichiometric under these conditions.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 141.210.2.78 Downloaded on 2015-06-04 to IP