Mechanochemical destruction of per- and polyfluoroalkyl substances in solvent-free solid media: a green remediation strategy.

The structural diversity of per- and polyfluoroalkyl substances (PFAS), together with the stringent requirement for deep defluorination and the substantial material and energy demands, poses considerable challenges for the implementation of destructive PFAS treatment technologies. Solvent-free mechanochemical destruction provides a promising alternative by enabling PFAS defluorination through the direct co-grinding of PFAS with reactive agents under sufficient mechanical energy input. The effectiveness of this approach is fundamentally governed by three key factors: the type of mechanochemical equipment, which directly determines the intensity of mechanical force and energy utilization efficiency; the amount of energy input received by the materials, which is intrinsically linked to reaction progress; and the selection of co-grinding agents, which critically influences both the broad-spectrum applicability and defluorination efficiency of PFAS treatment and must be carefully balanced against cost considerations. Mechanochemical destruction exhibits distinct advantages in achieving broad-spectrum defluorination and solid-state mineralization pathways with reduced reliance on solvents. With continued advances in energy optimization and system design, this technology is increasingly regarded as a viable and sustainable strategy for PFAS destruction, representing a significant breakthrough in addressing these persistent environmental contaminants. This review systematically summarizes the core conditions and key challenges of PFAS destructive treatment via mechanochemical methods, with ball milling as the primary approach.