Oxygen activity change in soda-lime-silica glass melts with or without refining agent

Abstract

The effect of refining agents in soda-lime-silica melts was examined by measuring the oxygen activity wi th the method of electromotive force. When the melt contained antimony, the activity changed with temperature and the Variation in activity increased as the antimony content increased. When the oxygen content in the atmosphere changed, the oxygen activity in the melt changed gradually by diffusion. The Variation in oxygen activity with atmosphere decreased with increasing antimony content and almost disappeared when the Sb₂O₃ content was 1 mol%. In the case of sulfate addition, the activity value became unstable when the temperature was raised, which might be caused by bubble formation accompanied by the decomposition of sulfate.