Biochar-based enzyme technology offers new path for cleaner water and soil

A growing body of research suggests that combining enzymes with biochar, a carbon-rich material made from agricultural and organic waste, could transform how scientists clean polluted water and soil. A new review published in Biochar provides the most comprehensive overview to date of how biochar-immobilized enzymes work, why they are effective, and what challenges remain before the technology can be widely applied.

Environmental pollution from industrial chemicals, dyes, pharmaceuticals, antibiotics, and heavy metals continues to threaten ecosystems and human health worldwide. Traditional treatment methods often rely on energy-intensive processes or chemical reagents that can generate secondary pollution. Enzymes offer a greener alternative because they are highly selective, operate under mild conditions, and break down pollutants into less harmful compounds. However, free enzymes are unstable, difficult to recover, and costly to reuse.

The review explains how immobilizing enzymes onto biochar can overcome these limitations. Biochar has a porous structure, large surface area, and diverse surface functional groups that allow enzymes to attach securely. Once immobilized, enzymes become more stable, easier to separate from treated water, and capable of repeated use.

“Biochar acts like a protective home for enzymes,” said one of the corresponding authors. “It concentrates pollutants near the enzyme surface while shielding the enzymes from harsh environmental conditions, which significantly improves both efficiency and durability.”

The authors analyze multiple immobilization strategies, including physical adsorption, encapsulation, covalent bonding, and cross-linking. Each method has advantages and tradeoffs. Physical adsorption is simple and low-cost, while covalent bonding offers superior long-term stability. The review highlights how tailoring biochar properties such as pore size, surface charge, and chemical functionality can precisely match enzyme structures and maximize performance.

In water treatment applications, biochar-immobilized enzymes have demonstrated impressive results. Studies show rapid removal of antibiotics, pharmaceutical residues, dyes, and phenolic compounds, often achieving near-complete degradation in hours or even minutes. In soil remediation, these systems not only break down contaminants but also improve soil water retention and provide habitats for beneficial microorganisms, supporting ecosystem recovery.

The review also emphasizes the synergistic effects of combining adsorption and enzymatic catalysis. Biochar captures pollutants from water or soil, holding them close to the enzymes that then chemically transform the contaminants into less toxic forms. This dual function makes the technology particularly attractive for treating complex pollution mixtures.

Despite its promise, the authors caution that large-scale application remains challenging. Variability in biochar feedstocks, enzyme deactivation over time, and potential ecological impacts require careful evaluation. The review calls for standardized production methods, long-term environmental safety studies, and life-cycle assessments to ensure the technology is both effective and sustainable.

Looking ahead, the researchers see opportunities to integrate advanced tools such as machine learning, smart materials, and multifunctional composites to further optimize biochar-enzyme systems. Magnetic biochars, for example, could enable easy recovery of catalysts, while engineered surfaces could improve enzyme compatibility and longevity.

“Biochar-immobilized enzymes represent a powerful intersection of green chemistry, waste valorization, and environmental engineering,” the authors said. “With continued innovation and careful risk assessment, this technology could play a key role in advancing low-carbon, sustainable solutions for pollution remediation.”

The review provides a roadmap for researchers and policymakers interested in translating laboratory successes into real-world environmental applications, offering a hopeful vision for cleaner water and healthier soils through nature-inspired design.

=== 

Journal Reference: Zhang, S., Cui, C., Huang, S. et al. Application and mechanisms of biochar-immobilized enzymes in environmental remediation: a review. Biochar 8, 4 (2026).   

https://doi.org/10.1007/s42773-025-00515-6  

=== 

About Biochar

Biochar (e-ISSN: 2524-7867) is the first journal dedicated exclusively to biochar research, spanning agronomy, environmental science, and materials science. It publishes original studies on biochar production, processing, and applications—such as bioenergy, environmental remediation, soil enhancement, climate mitigation, water treatment, and sustainability analysis. The journal serves as an innovative and professional platform for global researchers to share advances in this rapidly expanding field. 

Follow us on Facebook, X, and Bluesky.