Abstract
Purpose: Remediate metal contamination is a fundamental step prior to reclaim oil sands tailing ponds, and copper (Cu(II)) is the most abundant metal in the tailings water or oil sands process-affected water (OSPW). Biochars produced at four pyrolysis conditions were evaluated for sorption of Cu(II) in synthetic OSPW to explore different biochar potentials in removing Cu(II) from the contaminated water. Materials and methods: Pine sawdust biochars pyrolyzed at 300 and 550 °C with and without steam activation were investigated by batch sorption experiments. Isotherm and kinetic studies were conducted to compare the sorption capacities of the four biochars and to examine potential mechanisms involved. Results and discussion: For all the biochars, Langmuir and pseudo-second order models were the best-fit for isotherm and kinetic studies, respectively. According to the Langmuir parameters, the maximum adsorption capacities of the biochars produced at 550 °C were around 2.5 mg Cu(II) g−1, which were 30-folds higher than those produced at 300 °C. However, steam activation did not cause any significant difference in the biochars’ sorption performance. The kinetic study suggested that chemisorption involving valence forces was the limiting factor of the sorption. In addition, ion exchange and precipitation were likely the primary mechanisms for Cu(II) sorption which outweigh complexation with functional groups on the biochars’ surface. Conclusions: Pine sawdust biochar produced at 550 °C without steam activation could be utilized as a sustainable and cost-effective material to remove Cu(II) from the OSPW.
Original language | English |
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Pages (from-to) | 2081-2089 |
Number of pages | 9 |
Journal | Journal of Soils and Sediments |
Volume | 16 |
Issue number | 8 |
DOIs | |
Publication status | Published - 2016 Aug 1 |
Externally published | Yes |
Bibliographical note
Funding Information:This study was conducted with financial support from the Land Reclamation International Graduate School (LRIGS) that was funded by the NSERC CREATE program and the Helmholtz-Alberta Initiative at the University of Alberta.
Publisher Copyright:
© 2016, Springer-Verlag Berlin Heidelberg.
Keywords
- Adsorption isotherm
- Adsorption kinetics
- Black carbon
- Metal
- Oil sands process-affected water
- Steam activation
ASJC Scopus subject areas
- Earth-Surface Processes
- Stratigraphy