The Influence of Carbon Dioxide on the Melting of Glass

JSGT_1935_V19_T143_T150

The glass of standard composition SiO₂ 74, CaO 10, Na₂O 16% was prepared from batches containing the alkaline oxide as (a) InNa₂CO₃, (b) Na₂SO₄ (with carbon). The melting was performed in porcelain, in an electric furnace, in four hours at 900°, 1000°, 1200° and 1300°, and in atmospheres of air and CO₂ respectively. When melted in CO₂, the products from the soda ash batches contained a maximum of residual CO₂ of 0·13% at 900° diminishing to 0·05% at 1300°; those from the sulphate batches contained a maximum (at 1100°) of 11·99% of the original sulphate and 0·12%. CO₂  the respective amounts after melting at 1300°being 0·68% SO₃and 0·05% CO₂. On melting in air the residual CO₂ and SO₃ were all somewhat lower.

M. A. Besborodov, A. A. Sokolova & G. A. Shinké