Effects of nitrogen doped-biochar on wastewater remediation

Removal of toxic pollutants from wastewater is equally important for aquatic ecology, human health, and sustainable societal development.Nitrogen-doped biochar (N-BC) is a novel carbon-rich material that can effectively remove various pollutants by the high-temperature pyrolysis of waste biomass. In the current work, the physicochemical properties of endogenous and exogenous biochar (BC) including differences in porosity, specific surface area, elemental composition, and active functional groups were compared and summarized. Subsequently, the application of N-BC to degrade pollutants in wastewater was reviewed according to different surface morphological characteristics of endogenous and exogenous BC. To better understand the interactions between N-BC and pollutants, the interaction mechanism was analyzed, especially by adsorption, surface redox, and catalytic reaction. Finally, the current technical bottlenecks in the field of sewage treatment were pointed out and future research directions were proposed. The work can serve as a valuable reference for high-value conversion of biomass and targeted preparation of N-BC to maximize environmental, social, and economic benefits.