Mechanochemical reactions of ilmenite

Natural ilmenite samples (containing both FeTiO 3 and Fe 2 Ti 3 O 9 phases) have been ball milled in two atmospheres (vacuum and air) Different mechanochemical reactions were observed and the reaction processes were investigated by analysing the as-milled samples using X-ray diffraction and Mössbauer spectroscopy. A reduction reaction occurred during milling in vacuum because of the iron contamination, while an oxidation reaction was induced in the atmosphere of air with formation of thermally metastable phases, which corresponds to a low-temperature oxidation reaction in a thermal annealing process. The different products of milling in two atmospheres result in different chemical reactivities for the milled ilmenite samples.