Bochar from typical Vietnamese biomass residues (acacia wood chip, rice husk, bamboo) were assessed for application in remediation of metal-contaminated water. The biochar physical (e.g., surface area, morphology) and chemical (e.g. surface functional groups, proximate and elemental analysis) characteristics were correlated with their effectiveness in removing zinc (Zn 2+). The impact of biochar dose, contact time, and initial adsorbate concentration were investigated to determine the adsorption capacity of the biochar for Zn 2+. All three effectively remove Zn 2+ from aqueous solution, with bamboo biochar especially efficient (removal of 96–98% Zn 2+ from 40 to 80 mg/L). Maximum adsorptions were 7.62, 4.02, and 3.82 mg Zn 2+/L for bamboo, wood, and rice husk biochar, respectively. The Freundlich model fit the adsorption of Zn 2+, and a pseudo-second order model described the adsorption kinetics. Adsorption was governed by chelation with biochar organic groups (-COOH, -OH −) and precipitation onto inorganic groups (CO 3 2−, PO 4 2−), not ion exchange.
Bibliographical noteFunding Information:
The authors would like to thank the Vietnamese government for funding via the Ministry of Agriculture and Rural Development (MARD) and the Vietnam International Education Development (VIED) - Ministry of Education and Training , known as “The priority programme of development and application of biotechnology to agriculture and rural development up to 2020” (Grant Agreement No 11/2006 //QĐ -TTg). Additional support and funding for the project came from EU FP7 Marie Curie Career Integration Grant EcofriendlyNano (Grant Agreement no. PCIG14-GA-2013-631612 ). The authors acknowledge excellent technical support from Dr. Maria Thompson (University of Birmingham, UK) and Le Xuan Anh (Soils and Fertilizers Research Institute, Vietnam).
© 2020 The Author(s)
Copyright 2020 Elsevier B.V., All rights reserved.
- Adsorption isotherm
- Adsorption mechanism
- Functional groups
- Inorganic groups
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Environmental Engineering
- Waste Management and Disposal