Abstract:With the continuous progress of urbanization and industrialization, the generation of global organic solid waste has increased sharply. This surge exacerbates environmental pollution and results in significant resource waste. Efficient and sustainable management of such waste has become a critical research topic in global environmental governance and resource utilization. Biochar, a carbon material with excellent environmental adaptability and multifunctionality, has gained prominence as a focal point of research due to its potential applications in organic waste treatment, soil improvement, water remediation, and pollutant adsorption. This paper reviews the preparation methods, influencing factors, and applications of biochar in environmental remediation. Various technological pathways for converting organic solid waste into biochar have been summarized, including pyrolysis, gasification, hydrothermal carbonization, and microwave pyrolysis, as well as exploring the impact of these technologies on biochar properties. To optimize biochar performance, this paper examines biochar modification techniques, focusing on three main approaches: physical, chemical, and biological modifications. Physical modification primarily enhances the adsorption performance of biochar through methods such as physical activation and thermal treatment. Chemical modification introduces various chemical agents to improve biochar′s adsorption capacity for specific pollutants or to enhance its electrochemical properties. Biological modification combines biochar with microorganisms or plants to further improve its biodegradability and ecological adaptability. Moreover, the paper extensively discusses the potential applications of biochar in practical scenarios. In water purification, the porous structure and surface functional groups of biochar enable it to effectively adsorb dissolved organic and inorganic pollutants, thereby reducing the concentration of harmful substances in water bodies. In soil improvement, biochar enhances the physical and chemical properties of soil, increases soil fertility, improves aeration, and promotes plant growth, duo to its high specific surface area and rich nutrients. Additionally, the potential of biochar in carbon sequestration has garnered widespread attention. By converting organic waste into biochar, atmospheric carbon dioxide can be effectively sequestered, reducing greenhouse gas emissions and contributing to mitigating global climate change. Despite its promising applications across multiple fields, research on the long-term environmental impacts and potential risks of biochar remains relatively limited. At the same time, challenges such as the cost of biochar production, raw material availability, and the feasibility of large-scale production require further attention. To promote the widespread adoption of biochar technology, future research should focus on biochar’s behavior in different environments, assess its long-term ecological effects, and develop cost-effective and efficient production methods. Additionally, the socioeconomic benefits of biochar should become a key focus in future studies. Close-