Mechanochemical strategies for environmental remediation and resource recovery

Mechanochemistry is emerging as a distinct strategy for the sustainable conversion of recalcitrant substrates (per- and polyfluoroalkyl substances (PFAS), and spent batteries), as well as small molecules such as carbon dioxide (CO₂) and nitrogen (N₂) into valuable chemical products. By harnessing mechanical force, mechanochemical processes can promote chemical transformations under relatively mild, and solvent-free conditions, while potentially reducing hazardous emissions and simplifying process requirements. However, a coherent mechanistic framework and consistent sustainability evaluation remain underdeveloped. This review synthesizes the key mechanistic pathways, including radical and reactive intermediate generation, electron transfer, solid-gas interface activation, impact-driven micro-temperature (T)/pressure (P), phase transformation, and catalyst-assisted mechanoredox. These mechanistic insights are discussed together with advanced characterization techniques and integrated with techno-economic analysis (TEA), life cycle assessment (LCA), product sustainability index (ProdSI), and uncertainty analysis. By highlighting both opportunities and limitations, this Review aims to provide a balanced framework for guiding the future development of mechanochemical technologies for environmental remediation and resource recovery.