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Title: Chemical activation of biochar for energy and environmental applications: a comprehensive review
Abstract Biochar (BC) generated from thermal and hydrothermal cracking of biomass is a carbon-rich product with the microporous structure. The graphene-like structure of BC contains different chemical functional groups (e.g. phenolic, carboxylic, carbonylic, etc.), making it a very attractive tool for wastewater treatment, CO 2 capture, toxic gas adsorption, soil amendment, supercapacitors, catalytic applications, etc. However, the carbonaceous and mineral structure of BC has a potential to accept more favorable functional groups and discard undesirable groups through different chemical processes. The current review aims at providing a comprehensive overview on different chemical modification mechanisms and exploring their effects on BC physicochemical properties, functionalities, and applications. To reach these objectives, the processes of oxidation (using either acidic or alkaline oxidizing agents), amination, sulfonation, metal oxide impregnation, and magnetization are investigated and compared. The nature of precursor materials, modification preparatory/conditions, and post-modification processes as the key factors which influence the final product properties are considered in detail; however, the focus is dedicated to the most common methods and those with technological importance.  more » « less
Award ID(s):
1632899
PAR ID:
10091641
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Reviews in Chemical Engineering
Volume:
0
Issue:
0
ISSN:
0167-8299
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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