Solubility of Ag2O in the B2O3-Al2O3 system

The variation of Ag2O solubility under air atmosphere with the chemical pot ential of Ag was measured for the B2O3-Al2O3 system by equilibrating with a Ag-Au alloy with various Ag contents at 1373 K. It was found that, in this system, the regular solution model is not valid for estimating the activit y coefficient over a wide composition range. The activity coefficient of Ag 2O in B2O3 at infinite dilution and first order Gibbs energy interaction co efficients of Ag2O, Al2O3, and Na2O on the Ag2O were determined from Ag2O s olubility data without assuming a regular solution. The solubility of Al2O3 in berate melts is also discussed. (C) 1999 Elsevier Science B.V. All righ ts reserved.