Location: Soil and Water Management ResearchTitle: Characteristics and applications of biochar for environmental remediation: A review Author
Submitted to: Critical Reviews in Environmental Science Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/18/2014
Publication Date: 5/21/2014
Publication URL: http://handle.nal.usda.gov/10113/59595
Citation: Xie, T., Reddy, K.R., Wang, C., Yargicoglu, E., Spokas, K.A. 2014. Characteristics and applications of biochar for environmental remediation: A review. Critical Reviews in Environmental Science Technology. DOI: 10.1080/10643389.2014.924180. Interpretive Summary: Biochar has been gaining attention, both in the public and scientific circles, as a means to combat climate change and at the same time improve soil fertility. However, there has been less attention focused on the impact of biochar additions on environmental remediation efforts. In this review, we summarized the existing knowledge of biochar’s use for other environmental uses besides soil applications. The impact of biochar was dependent on the characteristics of the biochar, since all biochars are not equal in terms of their chemical and physical make-up. The sorption of the agrochemicals was impacted the most by biochar that has a high surface area and a low amount of dissolvable organic matter on the biochar. Thereby, this research highlights that biochar amendments need to be selected based on the desired mode of action and not all biochar types are suitable for sorbing all chemicals. Additional research is needed to fully characterize the surface chemistry responsible for these effects. These findings could provide additional insight and direction in the focus of the benefits of biochar additions. These findings are significant to farmers and policy makers and will assist scientists and engineers in developing improved biochars based on properties to minimize agrochemical transport and improve soil carbon management.
Technical Abstract: Biochar is a stabilized, recalcitrant organic carbon compound, created when biomass is heated to temperatures usually between 300 and 1000 degrees celsius, under low (preferably zero) oxygen concentrations. It is produced from a variety of biomass feedstocks, such as agricultural residues, wood chips, manure and municipal solid waste, through thermal treatment processes, among which slow pyrolysis is the most widely used process due to its moderate operating conditions and optimal biochar yield. Despite the recent introduction of a new term ‘biochar’ for this material, there have been several applications of charred materials in the past due to their unique properties. The objective of this review is to provide a detailed examination into engineering properties and potential uses of biochar as an engineered material for environmental remediation applications. The benefits of biochar use have primarily been recognized initially on soil amendment applications in agriculture; though other applications in environmental remediation engineering (e.g., remediation of contaminated soils, sediments, wastewater and groundwater) may be equally important. Biochar, due its enormous customizable surface chemistry, offers great potential in the environmental remediation applications and some of the potential applications are yet to be discovered.