What Is The Role Of Sodium Sulfate In Glass Production?

Sodium sulfate (Na2SO4) is commonly used as a fining agent in glass production to remove small air bubbles and other impurities from molten glass. When added to the glass melt, sodium sulfate reacts with any residual calcium oxide (CaO) to form calcium sulfate (CaSO4), which has a higher melting point than the surrounding glass. As the glass cools and solidifies, the calcium sulfate particles act as nucleation sites for crystallization, attracting any remaining impurities and causing them to form larger particles that can be easily removed from the surface of the glass. Sodium sulfate also helps to improve the viscosity and homogeneity of the glass melt, facilitating the formation of a uniform glass product.