A kinetic study of mechanically activated atom exchange: the effect of milling frequency and ball mass.

This study investigates the mechanochemical reaction of hydrogen isotope exchange between solid benzoic acid and liquid heavy water. The systematic change of milling conditions revealed that the reaction rate scales with the milling frequency and the mass of the milling balls. The ball size being always the same, faster reactions stem from the use of higher milling frequencies and heavier balls. The kinetic curves are described by a kinetic model that accounts for the statistical, deformational and chemical factors involved in mechanochemical transformations. The results indicate that the reaction is driven by the generation of a new interface area caused by the deformation of the solid reactants.