Alfin Kurniawan, Suryadi Ismadji, Chun Hui Zhou
Biochar is a low-cost, ecofriendly, and sustainable porous carbon-rich material that shows potential applications for environmental management and remediation. With regard to the latter, the modifications of textural and surface chemical properties of biochar, including surface area, pore structure, functional groups, and surface charge play an important role in enhancing the adsorption capacity and selectivity toward target pollutants for efficient water and wastewater treatment. In the present contribution, we provide an overview and discuss the structural and functional modification strategies of biochar to develop low-cost high-efficiency sorbents for removing toxic organic (polar and nonpolar) and inorganic (i.e., heavy metals and oxyanions) pollutants from aqueous environments via adsorption, precipitation, and heterogeneous advanced oxidation processes (AOPs). Extrinsic and intrinsic factors that govern pollutant removal ability of functional biochar in the above processes are discussed. Moreover, recent advances in the atomic-level characterization and computational techniques (i.e., density functional theory calculation and molecular dynamics) for elucidating surface physicochemistry-sorption relationships and providing a deeper understanding of the pollutant removal mechanism are presented. Furthermore, the challenges and future directions for designing and fabricating advanced biochar sorbents in the context of sustainable industrial wastewater treatment are identified. © 2024 American Chemical Society.
Research Group for Advanced Materials and Sustainable Catalysis (AMSC), State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310032, China; Department of Chemical Engineering, Widya Mandala Catholic University Surabaya, Kalijudan 37, Surabaya, 60114, Indonesia; Collaborative Research Center for Zero Waste and Sustainability, Widya Mandala Catholic University Surabaya, Kalijudan 37, Surabaya, 60114, Indonesia