Biochar as a Sorbent for Contaminant Management in Soil and Water: A Review
Mahtab Ahmad1,2, Anushka Upamali Rajapaksha1, Jung Eun Lim1, Ming Zhang3, Nanthi Bolan4, Dinesh
Mohan5, Meththika Vithanage6, Sang Soo Lee1, and Yong Sik Ok1,3,7*
1
Korea Biochar Research Center, Kangwon National University, Chuncheon 200-701, Korea
2
University Institute of Biochemistry and Biotechnology, PMAS Arid Agriculture University, Rawalpindi,
Pakistan
3
Department of Environmental Engineering, China Jiliang University, Hangzhou, Zhejiang 310018, P.R.
China
4
Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson
Lakes, SA, Australia
5
School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
6
Chemical and Environmental Systems Modeling Research Group, Institute of Fundamental Studies,
Kandy, Sri Lanka
7
Department of Renewable Resources, University of Alberta, Alberta, Canada
*
Corresponding author
Tel: +82-33-250-6443
Email: soilok@kangwon.ac.kr
Address: Korea Biochar Research Center, Kangwon National University, Chuncheon 200-701, Korea
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Abstract
Biochar is a stable carbon-rich-solid developed by biomass pyrolysis/carbonization. An increasing interest
in biochar has opened up multidisciplinary areas for science and engineering. The potential biochar
applications include carbon sequestration, soil fertility improvement, pollution remediation, and
agricultural by-product/waste recycling. The key parameters controlling its properties include pyrolysis
temperature, residence time, heat transfer rate, and feedstock type. The efficacy depends on surface area,
pore size distribution and ion-exchange capacity of biochar. Physical architecture and molecular
composition of biochar could be critical for practical application to soil and water. Relatively high
pyrolysis temperatures generally produce more effective biochars as organic contaminants’ sorbents by
increasing surface area, microporosity, and hydrophobicity, whereas the biochars obtained at low
temperatures are suitable for removing inorganic/polar organic contaminants by high oxygen-containing
functional groups, electrostatic attraction, and precipitation. However, due to soil-water system
complexity in nature, the effectiveness of biochars on remediation of various organic/inorganic
contaminants is still uncertain. In this review, a succinct summary of current biochar use as a sorbent for
contaminant management in soil and water is summarized and discussed.
Keywords: Black carbon; Charcoal; Activated carbon; Slow pyrolysis; Bioavailability; Amendment
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