Application and mechanisms of biochar-immobilized enzymes in environmental remediation: a review

Abstract As environmental pollution becomes an increasingly severe issue, the technology of enzyme immobilization on biochar has emerged as a promising solution for water and soil pollution remediation due to its efficiency, cost-effectiveness, and environmental friendliness. This review systematically examines the preparation methods, adaptation mechanisms, and applications of biochar-immobilized enzymes for pollutant removal. It focuses on the interaction between enzymes and biochar carriers, the selection of immobilization techniques, and the stability of immobilized enzymes. Biochar, as a carrier, offers advantages such as low cost, high specific surface area, and a variety of surface functional groups, which can be further enhanced through modification techniques to optimize its compatibility with enzymes. The review also discusses the strengths and weaknesses of various immobilization strategies, highlighting the high stability of covalent binding and the cost-effectiveness of adsorption methods. In the field of environmental remediation, biochar-enzyme composites have demonstrated synergistic effects in efficiently degrading organic pollutants, decoloring dyes, and remediating soil contaminants. While significant progress has been made in laboratory studies, the large-scale application of biochar-immobilized enzymes still faces numerous challenges, including raw material heterogeneity, enzyme deactivation, and ecological safety concerns. Future research should focus on developing intelligent design platforms, optimizing biochar-enzyme compatibility, overcoming the limitations of multifunctional synergistic remediation, and evaluating the long-term ecological impact. By integrating multiple technologies, biochar-immobilized enzymes hold great potential for widespread application in environmental remediation, advancing green and low-carbon technologies. Graphical Abstract