Characterization of hard- and softwood biochars pyrolyzed at high temperature.
A wide range of waste biomass/waste wood feedstocks abundantly available at mine sites provide the opportunity to produce biochars for cost-effective improvement of mine tailings and contaminated land at metal mines. In the present study, soft- and hardwood biochars derived from pine and jarrah woods at high temperature (700 °C) were characterized for their physiochemical properties including chemical components, electrical conductivity, pH, zeta potential, cation-exchange capacity (CEC), alkalinity, BET surface area and surface morphology. Evaluating and comparing these characteristics with available data from the literature have affirmed the strong dictation of precursor type on the physiochemical properties of the biochars. The pine and jarrah wood feedstocks are mainly different in their proportions of cellulose, hemicellulose and lignin, resulting in biochars with heterogeneous physiochemical properties. The hardwood jarrah biochar exhibits much higher microporosity, alkalinity and electrostatic capacity than the softwood pine. Correlation analysis and principal component analysis also show a good correlation between CEC-BET-alkalinity, and alkalinity-ash content. These comprehensive characterization and analysis results on biochars' properties from feedstocks of hardwood (from forest land clearance at mine construction) and waste pine wood (from mining operations) will provide a good guide for tailoring biochar functionalities for remediating metal mine tailings. The relatively inert high-temperature biochars can be stored for a long term at mine closure after decades of operations.
Centre of Mined Land Rehabilitation, SMI, The University of Queensland, Brisbane, QLD, 4072, Australia.
Shasha
S
Jiang
Centre of Mined Land Rehabilitation, SMI, The University of Queensland, Brisbane, QLD, 4072, Australia.|School of Chemical Engineering, The University of Queensland, Brisbane, QLD, 4072, Australia.
Tuan A H
TA
Nguyen
School of Chemical Engineering, The University of Queensland, Brisbane, QLD, 4072, Australia.
Victor
V
Rudolph
Centre for Energy (M473), The University of Western Australia, Crawley, WA, 6009, Australia.
Hong
H
Yang
Centre for Energy (M473), The University of Western Australia, Crawley, WA, 6009, Australia.
Dongke
D
Zhang
Korea Biochar Research Centre and School of Natural Resources and Environment, Kangwon National University, Chuncheon, 24341, Korea.
Yong Sik
YS
Ok
Centre of Mined Land Rehabilitation, SMI, The University of Queensland, Brisbane, QLD, 4072, Australia. l.huang@uq.edu.au.
Longbin
L
Huang
D018533:Biomass; D002606:Charcoal / Q000737:chemistry*; D004553:Electric Conductivity; D052918:Environmental Restoration and Remediation; D005052:Eucalyptus; D006863:Hydrogen-Ion Concentration; D028223:Pinus; D013045:Species Specificity; D013499:Surface Properties; D013696:Temperature; D014934:Wood / Q000737:chemistry*
C540010:biochar; D002606:Charcoal
BET surface area; Biochar physicochemical characteristics; CEC–BET–alkalinity; Wood feedstocks; Wood-derived biochar