silica iron is a form of iron that is produced by the interaction between sand and water, as well as from other mineral sources. This is a key component in the production of glass bottles as well as other applications.
It is a natural mineral that can be found at most mining sites, including those in the sand industry. It is used to make clear and amber glass bottles.
The reactivity of silica is influenced by the pH of the solution it is in and by the chemical composition of the mineral. It is also influenced by the temperature. This is a problem for glass makers, especially in the sand industry where it is necessary to ensure that the metal is not present in the glass.
This reactivity can be inhibited by solid-state mixing of iron and amorphous silica. This can be accomplished using an experimental facility that incorporates both crystalline and amorphous silica powders in the same reaction.
A complete oxidation-reduction cycle was performed to test the recyclability of this mixture. In the oxidation step, the mixture was heated to 850degC and the iron was sintered. In the reduction step, carbon monoxide was added at a rate of 0.1 SLPM to lower the temperature and prevent further sintering.
The reactivity of iron with monomeric silicate polymers in acid solution has been studied (Weber and Swaddle, 1965; Olson and O’Melia, 1973; Reardon, 1979). The second shell of Fe3 in these compounds is hexa-coordinated. In contrast, the first shell is octahedral or tetrahedral coordinated. This suggests that a high pH of the silicate solution causes Fe3 to interact with silicic acid in an oxidative way (Swaddle, 2001).