Some aspects of mechanochemical reactions

Mechanochemistry, a branch of chemistry concerned with the chemical and physicochemical transformations of substances in all states of aggregation induced by mechanical energy, was formulated by Heinicke [1] more than twenty years ago and is currently fully accepted. Recently, mechanochemistry has become the subject of everincreasing interest in relation to the theory and preparation of advanced metastable solids – novel, high-performance, and low-cost composite materials with new properties such as better dissolution and leaching (especially important in the case of metals extracted from minerals), and faster decomposition and synthesis. Moreover, these materials also show an improvement in the sintering processes [2]. From the chemical point of view, the mechanical treatment of solids using high -energy impulses can cause mechanical activation, mechanical alloying, and reactive milling of solids. Communition, always the first step of these processes, is the multiple particle rupture which results in their size reduction and a simultaneous increase in the specific surface area and surface energy within the systems. Mechanical activation results in changes partly in the tension state and partly in the dispersion state. Milling can be viewed as a mechanochemical activation if these changes also involve alterations in the structure of the material, its chemical composition, and chemical