In a review published in Sustainability, Diego C. B. D. Santos et al. explored biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More production, characterization, and applications. The review emphasises that biochar’s properties are significantly influenced by the production process, including the feedstockFeedstock refers to the raw organic material used to produce biochar. This can include a wide range of materials, such as wood chips, agricultural residues, and animal manure. More and process parameters such as temperature, heating rate, and residence timeResidence time refers to the duration that the biomass is heated during the pyrolysis process. The residence time can influence the properties of the biochar produced.   More.  

Biochar, a carbon-rich material produced from biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More through thermochemical conversion, has garnered increasing attention for its wide-ranging applications. This interest is due to biochar’s versatility across various sectors, including agriculture, environmental remediation, and energy storage. The authors highlight that different thermochemical processes—torrefaction, pyrolysisPyrolysis is a thermochemical process that converts waste biomass into bio-char, bio-oil, and pyro-gas. It offers significant advantages in waste valorization, turning low-value materials into economically valuable resources. Its versatility allows for tailored products based on operational conditions, presenting itself as a cost-effective and efficient More, and gasification—yield biochar with distinct characteristics. For example, biochar produced through slow pyrolysis (300-650°C) primarily yields a significant fraction of solids (20-40%), while fast pyrolysis (above 500°C) maximises bio-oil production.  

The review emphasizes the importance of characterization to determine biochar’s suitability for specific applications. Techniques such as Fourier Transform Infrared (FTIR) spectroscopy, Raman spectroscopy, and Scanning Electron Microscopy (SEM) provide valuable insights into biochar’s chemical composition, structure, and surface morphology. The authors also highlight the importance of considering the atomic H/C and O/C ratios, as these ratios indicate biochar’s chemical stability, aromaticity, and surface reactivity.  

The review concludes that Multi-Criteria Decision Analysis (MCDA) is a valuable tool for optimising biochar production and application. By considering various criteria, including biochar properties and application requirements, MCDA can aid in selecting the most suitable production methods and feedstocks for specific uses. This approach will help to advance biochar technology and promote its sustainable and efficient use across various sectors.  

Source:Santos, D. C. B. D., Evaristo, R. B. W., Dutra, R. C., Suarez, P. A. Z., Silveira, E. A., & Ghesti, G. F. (2025). Advancing Biochar Applications: A Review of Production Processes, Analytical Methods, Decision Criteria, and Pathways for Scalability and Certification. Sustainability, 17(6), 2685.