Research progress of biochar modification technology and its application in environmental remediation.

Biochar can be prepared from biomass through pyrolysis in a low-oxygen or anaerobic environment. The characteristics of biochar are influenced by raw materials and the specific preparation process employed. To enhance the efficacy of biochar, various modification methods can be applied. These primarily include chemical modification, physical modification, and biological modification. This paper conducts a literature review covering the period from 2018 to 2023, focusing on biochar preparation, modification methods, and environmental applications. It is a comprehensive overview of the processes involved in preparing biochar, analyzes its characteristics, and explores various modification techniques. Additionally, the paper discusses the diverse and highly efficient application of biochar in environmental remediation, with a particular emphasis on its use in soil, water, and the atmosphere. While biochar holds significant potential for environmental remediation, a thorough understanding of its mechanism in environmental applications is still lacking. Further in-depth studies are required to elucidate the complex roles biochar plays in various environmental contexts. • A summary of the application of modified biochar to soil, water, and atmosphere remediation is presented to show its remediation effect. • Alkali modification of biochar greatly enhances its specific surface area. • Metal salt modification significantly boosts oxygen-containing functional groups in biochar. • Some research directions and future perspectives for modified biochar are highlighted. [ABSTRACT FROM AUTHOR]