Oxygen Ion Activity and the Solubility of Sulfur Trioxide in Sodium Silicate Melts

Abstract

The solubility of sulfur trioxide in sodium silicate melts was determined from 1150° to 1250°C by equilibrating melts in gas mixtures of known contents of sulfur dioxide and oxygen. Sulfate forms according to the reactions: O2‐+ SO2+ 1/2O2= O2‐+ SO3= SO42‐. The data obtained at 1200°C were interpreted by the linear equation: log(SO42‐) = log(Pso2½Po21/2) + log Y in which Y is a function of the soda/silica ratio. A series of parallel lines was obtained. Relative free oxygen ion activities calculated for 1200°C were in good agreement with theoretical values calculated from the thermodynamic model of Toop and Samis.

Summary of Fy11 Sulfate Retention Studies for Defense Waste Processing Facility Glass

“…12 Orton high temperature rotating spindle viscometers were used with platinum crucibles and spindles. The crucibles were specially designed to operate with small quantities of glass to support measurements of radioactive glasses when necessary.…”

Glass optimization for vitrification of Hanford Site low-level tank waste

“…Compared to L6-5412 glass, SO, was much less soluble in L4-9012 glass, which may be attributed to an overall reduction of NBO concentration in glass due to both a removal of CaO and an increase in B203, according to Holmquist (1966) and Papadopoulos (1977). It is not fully understood if an increase in solubility of Cr203 in L4-9012 glass is related to the change of CaO or to B203.…”

Preliminary Investigation of Sulfur Loading in Hanford LAW Glass

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