Removal of phosphate from aqueous solution by biochar derived from anaerobically digested sugar beet tailings
Abstract
Biochar converted from agricultural residues or other carbon-rich wastes may provide new methods and materials for environmental management, particularly with respect to carbon sequestration and contaminant remediation. In this study, laboratory experiments were conducted to investigate the removal of phosphate from aqueous solution by biochar derived from anaerobically digested sugar beet tailings (DSTC). Batch adsorption kinetic and equilibrium isotherm experiments and post-adsorption characterizations using SEM-EDS, XRD, and FTIR suggested that colloidal and nano-sized MgO (periclase) particles on the biochar surface were the main adsorption sites for aqueous phosphate. Batch adsorption experiments also showed that both initial solution pH and coexisting anions could affect the adsorption of phosphate onto the DSTC biochar. Of the mathematical models used to describe the adsorption kinetics of phosphate removal by the biochar, the Ritchie N_th-order (N=1.14) model showed the best fit. Two heterogeneous isotherm models (Freundlich and Langmuir-Freundlich) fitted the experimental isotherm of phosphate adsorption onto the biochar better than the Langmuir adsorption model. Our results suggest that biochar converted from anaerobically digested sugar beet tailings is a promising alternative adsorbent, which can be used to reclaim phosphate from water or reduce phosphate leaching from fertilized soils. In addition, there is no need to regenerate the exhausted biochar because the phosphate-laden biochar contains abundance of valuable nutrients, which may be used as a slow-release fertilizer to enhance soil fertility and to sequester carbon.
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Phosphate-laden biochar contained valuable nutrients that could act as a slow release fertilizer to enhance soil fertility and sequester C for a longer time in soil.
“Yao et al. (2011) also found that the phosphate-laden biochar contained valuable nutrients that could act as a slow release fertilizer to enhance soil fertility and sequester C for a longer time in soil.”
From A review on biochar modulated soil condition improvements and nutrient dynamics concerning crop yields: Pathways to climate change mitigation and global food security (2019) · cites this paper as Yao et al., 2011
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- Authors
- Yao, Y., Gao, B., Inyang, M., Zimmerman, A. R., Cao, X., Pullammanappallil, P., & Yang, L.
- Affiliations
- University of Florida (US)
- Shanghai Jiao Tong University (CN)
- Corresponding author
- Gao, Bin
- ORCID
- Venue
- Journal of Hazardous Materials
- Publisher
- Elsevier BV
- Published
- 2011-06
- Volume
- 190
- Issue
- 1-3
- Pages
- 501-507
- ISSN
- 0304-3894 (ISSN-L)
- OpenAlex
- W2125069595
- Cited by
- 614
- References
- 41
- Citations by year
- 2026: 19 · 2025: 38 · 2024: 45 · 2023: 35 · 2022: 54 · 2021: 64 · 2020: 61 · 2019: 61 · 2018: 44 · 2017: 50 · 2016: 48 · 2015: 28 · 2014: 32 · 2013: 20 · 2012: 12
- FWCI
- 42.31
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of Hazardous Materials (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Science Foundation
- U.S. Department of Agriculture
- Division of Chemical, Bioengineering, Environmental, and Transport Systems
- Topics
- Physical Sciences › Environmental Science › Waste Management and Disposal › Phosphorus and nutrient management
- Physical Sciences › Environmental Science › Water Science and Technology › Adsorption and biosorption for pollutant removal
- Physical Sciences › Environmental Science › Environmental Chemistry › Soil and Water Nutrient Dynamics
- Keywords
- phosphate removal, biochar, anaerobic digestion, adsorption, adsorption kinetics, adsorption isotherms, magnesium oxide, periclase, phosphate leaching, slow-release fertilizer, carbon sequestration, agricultural waste valorization
- MeSH terms
- Adsorption, Binding Sites, Carbon, Charcoal, Kinetics, Magnesium Oxide, Phosphates, Water Pollutants, Chemical, Clinical Laboratory Techniques, Beta vulgaris, Environmental Restoration and Remediation
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