Application of Biochar-Based Catalysts for Soil and Water Pollution Control

Abstract

Biochar materials produced from biomass pyrolysis offer promising functionality as sustainable and eco-friendly catalysts for activating peroxides and persulfates to treat aqueous and soil contaminants. This review summarizes recent progress, mechanistic insights, and future research needs regarding multifaceted biochar catalyst systems for in-situ remediation. For water treatment, biochar composites with transition metals, metal oxides, advanced carbon materials and heteroatom dopants have shown excellent activity for contaminant mineralization. Over 90–100% removal was achieved for dyes, pharmaceuticals, pesticides and hydrocarbons through redox, Fenton-like, sonocatalytic and photocatalytic pathways. In soil, amendments with tailored biochars reduced bioavailability and stimulated biotic/abiotic degradation of organics like PAHs and phthalates. Over 80–90% of phenanthrene, petroleum hydrocarbons and heavy metals were remediated via immobilization, electron transfer to pollutants, and activation of peroxides. Spectroscopic evidence suggests generation of reactive radicals along with direct electron transfer contributes appreciably. However, large-scale field testing is required to evaluate technological viability and environmental impacts. Overall, creative integration of green chemistry with remediation goals positions functionalized biochar catalysts well to address pressing soil and water pollution while advancing sustainability.