The impact of iron content in oxidation front in soda-lime silicate glasses: An experimental and comparative study

• Observation of oxidation fronts in two molten glasses with two iron contents.
• The iron content reduces the kinetics of front oxidation.
• A model is developed coupling O2 diffusion and oxidation–reduction reaction of Fe.
• From a scaling and a numerical analysis, a selfsimilar solution is provided.
• A law of oxidation front velocity is given and used to merge the experimental data.

Experiments on the oxidation front in two soda-lime silicate glasses melted at 1400 °C are first reported. The length of the oxidation front is proportional to the square root of time and the kinetics is three times slower when the iron content changes from 0.08 to 0.64 wt.%. A theoretical model is drawn assuming that the oxidation process is driven by the diffusion of oxygen coupled to the oxidation–reduction reaction of iron. From scaling analysis, numerical and self-similar solutions, the length of the oxidation front as a function of time is rescaled taking into account the iron content and the oxygen saturation in molten glass. The experimental results of oxidation front merge in a master curve demonstrating the relevance of the theoretical developments.