Mechanochemistry: the varied applications of mechanical bond-breaking

Abstract

Images reproduced with permission of Tomislav Friscic (left) and Reiko Kuroda (right) Papers published in this issue include: Mechanochemistry: the varied applications of mechanical bond-breaking

An environmental benign process for cobalt and lithium recovery from spent lithium-ion batteries by mechanochemical approach

“…4b, no reflections of EDTA was observed and the reflections of LiCoO 2 became weaker after ball milling treatment. The inner energy of crystal lattice was enhanced after mechanical activation treatment, which was feasible for atomic transition (Kaupp, 2009). In fact, the following water leaching process was a disordering diffusion process for the activated material in water.…”

Organic Solid-State Reactions

“…Furthermore, the "reinventors" still often "add a little solvent" (mostly about 10%, or two drops that are usually overstoichiometric), or they unduly call everything "mechanochemistry" that involves a mortar or a mill together with molecular or salt reactions, that is, comminution and mixing, but always the reaction is under thermodynamic control (they do not deal with decompositions of molecules by shearing under a Bridgeman's anvil). Such mechanistic claims are false and misleading when no mechanical breakage of chemical bonds occurs (as in the mechanochemistry by hitting flint, polishing, grinding weak-bond radical formers, initiating explosives, shearing under Bridgman's anvil, performing polymer mastication, greasing of brakes, cutting nanodissections, etc., which covers a totally different huge field of chemistry without thermodynamic control [32]). Unfortunately, the false mechanistic claims are sometimes even made for kneading of liquid or viscous dough in a mortar or in a planetary mill at unknown high temperature, while it would be much cheaper and more profitable to stir and use a thermostated bath for these reactions.…”

“…A comprehensive review of mechanochemistry is given in Ref. [32]. At molecular and salt solid-solid reactions, the molecules (ions) escape the milling impact that comminutes the solids.…”

Solvent-Free Biginelli Reactions Catalyzed by Hierarchical Zeolite Utilizing a Ball Mill Technique: A Green Sustainable Process

“…It is known that the powered initiation of solids leads to a rise in outer surface area, exterior energy and surface defects. The augmented superficial energy can result in a mechano-chemical initiation if changes in assembly, chemical structure or chemical reactivity happened during milling [53].…”