Engineered biochar emerges as a powerful, affordable tool to combat water pollution
Biochar Editorial Office, Shenyang Agricultural University
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Engineered biochar for simultaneous removal of heavy metals and organic pollutants from wastewater: mechanisms, efficiency, and applications
view moreCredit: Nana Wang, Bing Wang, Hailong Wang, Pan Wu, Masud Hassan, Shengsen Wang & Xueyang Zhang
A new comprehensive study highlights the remarkable potential of engineered biochar, a carbon-rich product derived from plant and waste biomass, for addressing one of the world’s most stubborn environmental problems: the co-contamination of water by heavy metals and organic pollutants. This joint effort, led by researchers at Guizhou University with collaborators from across China, reveals how strategic modifications to biochar’s structure dramatically expand its ability to capture and remove hazardous substances from wastewater, making it a viable, sustainable solution for water treatment in diverse settings.
Water pollution by both toxic metals and organic chemicals is a globally recognized crisis. Runoff from factories, farms, and urban areas releases contaminants like lead, chromium, pharmaceuticals, dyes, and pesticides into rivers, lakes, and groundwater. When these pollutants co-exist, their combined effects are often more dangerous and more difficult to treat than when they appear alone. Many existing technologies struggle to deal with complex mixtures because they often target only one pollutant type at a time or require expensive, energy-intensive processes.
Biochar, sometimes nicknamed “black gold for the environment,” is produced by heating agricultural or industrial waste in limited oxygen. The result is a stable, highly porous material with a large surface area, making it an ideal candidate for environmental cleanup. In recent years, scientists have enhanced biochar’s natural adsorptive properties by integrating metal oxides, polymers, or even graphene, creating “engineered biochar” with tailored surface chemistry and structure. This innovation allows for the efficient capture of both heavy metals and a variety of organic contaminants simultaneously, using mechanisms such as electrostatic attraction, bridging interactions, and pore filling.
The review summarizes dozens of real-world case studies and laboratory experiments, showing that properly modified biochars can remove multiple contaminants with high efficiency. For instance, engineered composites made from biochar and certain metal oxides outperformed standard materials in capturing lead and organic dyes from industrial effluent. Other research demonstrated that magnetic or polymer-infused biochars achieved not only excellent removal rates for metals and antibiotics but could also be easily separated and reused, reducing operational costs.
Importantly, the environmental and economic benefits of biochar go beyond pollutant removal. Biochar production helps recycle agricultural and forestry byproducts that would otherwise go to waste. Its wide availability and low manufacturing cost make it especially attractive for developing regions, while its ability to be regenerated and used over multiple cycles adds to long-term sustainability.
The review also outlines key challenges and directions for future research. These include optimizing biochar formulations for specific contamination scenarios, ensuring the safe disposal or regeneration of pollutant-laden material, and conducting rigorous risk assessments to minimize unintended ecological effects. The authors highlight the importance of green and low-cost modification methods to further improve environmental compatibility.
This study provides a strategic roadmap for translating engineered biochar from laboratory innovations to full-scale water treatment solutions. With growing pressure on global freshwater resources and tightening environmental standards, engineered biochar offers a practical and scalable tool for governments, industries, and communities in the fight against water pollution. The findings are expected to spark further collaborations and investments in sustainable environmental remediation technologies.
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Journal reference: Wang N, Wang B, Wang H, Wu P, Hassan M, et al. 2025. Engineered biochar for simultaneous removal of heavy metals and organic pollutants from wastewater: mechanisms, efficiency, and applications. Biochar X 1: e008
https://www.maxapress.com/article/doi/10.48130/bchax-0025-0008
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About the Journal:
Biochar X is an open access, online-only journal aims to transcend traditional disciplinary boundaries by providing a multidisciplinary platform for the exchange of cutting-edge research in both fundamental and applied aspects of biochar. The journal is dedicated to supporting the global biochar research community by offering an innovative, efficient, and professional outlet for sharing new findings and perspectives. Its core focus lies in the discovery of novel insights and the development of emerging applications in the rapidly growing field of biochar science.
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Method of Research
Literature review
Subject of Research
Not applicable
Article Title
Engineered biochar for simultaneous removal of heavy metals and organic pollutants from wastewater: mechanisms, efficiency, and applications
Microalgal-bacterial sludge offers sustainable solution for removing hormonal pollutants from wastewater
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Metabolic responses and biodegradation pathways of microalgal-bacterial granular sludge to estriol: structural remodeling, microbial shifts, and gene dynamics
view moreCredit: Yuting Shi, Changqing Chen, Bingyi Ding, Yaorong Shu, Jie Feng, Anjie Li & Bin Ji
A team of researchers in China has developed a promising biotechnological approach that could help communities worldwide tackle the challenge of wastewater contamination by hormone-like pollutants. Their study reveals how microalgal-bacterial granular sludge (MBGS) can adapt and efficiently degrade estriol, a common endocrine-disrupting compound (EDC), under environmentally relevant conditions.
Estriol, a natural estrogen present in domestic sewage, hospital effluent, and pharmaceutical waste, is known for its persistence and biological activity, even at very low concentrations. Standard wastewater treatment plants are often unable to fully remove these compounds due to their low biodegradability and resistance to microbial breakdown. This can lead to environmental pollution and potential risks to human and ecological health.
To address these concerns, the research team, led by Yuting Shi at Wuhan University of Science and Technology and collaborators at Huazhong University of Science and Technology and Beijing Normal University, tested the performance of MBGS under a range of estriol concentrations that reflect both typical and worst-case scenarios found in wastewater streams.
MBGS is a self-aggregated system that combines the functions of photosynthetic microalgae and heterotrophic bacteria within a granular structure. This arrangement enhances the removal of both organic matter and nutrients, while also providing internal cycling of oxygen, which is crucial for breaking down difficult pollutants. The presence of certain bacteria known for their EDC-degrading potential further boosts the system’s capabilities.
In experiments, the team exposed MBGS to various concentrations of estriol—ranging from levels found in most municipal wastewater to those in heavily contaminated industrial sources. The results were striking: At a realistic low dose of 0.1 mg/L, MBGS achieved up to 98 percent removal of estriol during daylight hours, demonstrating both speed and efficiency. Even more impressively, the system adapted to repeated exposures, maintaining strong performance over time.
The researchers traced the removal mechanism to a two-step process. First, estriol is quickly adsorbed onto the granular sludge through interactions with microbial extracellular substances. Then, specialized bacteria take over, breaking the compound down into less toxic intermediates and finally into harmless end products. Genetic analysis revealed that families such as Sphingomonadaceae and Rhodanobacteraceae play a critical role in this process, activating a suite of enzymes that catalyze the stepwise breakdown of estriol’s molecular structure.
However, the study also found limits to this resilience. When exposed to higher doses (1 and 10 mg/L), which might occur in direct pharmaceutical or hospital waste, MBGS suffered structural damage, particularly to the supportive cyanobacteria forming the granule skeleton. This led to a decline in removal efficiency and destabilized the sludge structure. Key functional genes and microbial populations responsible for removing pollutants were also suppressed at these higher concentrations.
Despite this, the findings underscore the potential of MBGS for sustainable, cost-effective treatment of wastewater containing hormone pollutants. By harnessing the natural synergies between microalgae and bacteria, treatment plants could boost removal of dangerous estrogens and protect aquatic environments more effectively.
The research was supported by the National Natural Science Foundation of China and demonstrates the critical role that innovative microbiological solutions can play in advancing environmental protection and public health.
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Journal reference: Shi Y, Chen C, Ding B, Shu Y, Feng J, et al. 2025. Metabolic responses and biodegradation pathways of microalgal-bacterial granular sludge to estriol: structural remodeling, microbial shifts, and gene dynamics. Biocontaminant 1: e004
https://www.maxapress.com/article/doi/10.48130/biocontam-0025-0004
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About Biocontaminant:
Biocontaminant is a multidisciplinary platform dedicated to advancing fundamental and applied research on biological contaminants across diverse environments and systems. The journal serves as an innovative, efficient, and professional forum for global researchers to disseminate findings in this rapidly evolving field.
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Method of Research
Experimental study
Subject of Research
Not applicable
Article Title
Metabolic responses and biodegradation pathways of microalgal-bacterial granular sludge to estriol: structural remodeling, microbial shifts, and gene dynamics
Article Publication Date
3-Nov-2025
