Critical impacts of pyrolysis conditions and activation methods on application-oriented production of wood waste-derived biochar

• Published in: Bioresource technology Vol. 341; p. 125811
• Main Authors: He, Mingjing, Xu, Zibo, Sun, Yuqing, Chan, P.S., Lui, Iris, Tsang, Daniel C.W.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2021
• Subjects: Activation method; biochar; carbon dioxide; circular economy; dissolved organic carbon; Engineered biochar; Physicochemical properties; pyrolysis; Pyrolysis condition; steam; Sustainable waste management; technology; temperature; waste management; waste wood; wood; Engineered biochar; Pyrolysis condition; Activation method; Physicochemical properties; Sustainable waste management
• ISSN: 0960-8524; 1873-2976; 1873-2976
• DOI: 10.1016/j.biortech.2021.125811

[Display omitted] •Co-impacts of pyrolysis conditions and activation methods on biochar were studied.•Pyrolysis temperature was the most influential factor on biochar properties.•750 ℃ was the critical temperature for wood-based biochar to form porous structure.•Steam-activated biochar pyrolyzed at 850 ℃ displayed the highest mesopores formation.•Fit-for-purpose biochar production is critical for its commercial/environmental benefits. Wood waste-derived biochar with tunable carbon structure and surface functionality has a great potential for various environmental applications and circular economy; however, a holistic understanding on the application-oriented production of high-efficacy biochar is lacking. Thus, the co-impacts of different pyrolysis conditions (temperature and duration) and activation methods (steam, CO2, and acid pretreatment) on the biochar properties were first investigated. A temperature of 650 ℃ was effective in forming carbonized structure in biochar, while 750 ℃ was critical for the porous structure development. A longer pyrolysis duration (>60 min) enhanced the pore volume without compromising the yield. The activated biochar exhibited a larger pore volume (2.1- to 2.9-fold of pristine biochar) for potential high-end emerging applications. The acid pretreatment effectively removed dissolved organic carbon and most metals from the biochar. This study provides an essential guidance on the fit-for-purpose designs of biochar production conditions for sustainable wood waste management.