Abstract
Carbon-based sorbents have been proven to be cost-effective in removing pollutants from wastewater. Biochar from plant residue and agricultural waste is an emerging treatment technology. However, there is a limited number of studies on the effects of various biochar sources on metal adsorption. The aim of this study was using batch experiment to evaluate the adsorption of heavy metals in single- and multi-metal conditions onto pepper stem biochar. The maximum adsorption capacities (mg g−1) of metals by pepper stem biochar were in the order of Pb (131) » Cr (76) > Cd (67) > Cu (48) > Zn (31) in the single-metal adsorption isotherm and Pb (91) » Cu (39) > Cr (29) > Zn (20) > Cd (13) in the multi-metal adsorption isotherm. Lead was the most retained cation, whereas Cr and Cd could be easily exchanged and substituted by other metals (Pb or Cu). For pepper stem biochar, the Langmuir model provided a slightly better fit than the Freundlich model. Results from the batch experiments show that competitive adsorption among metals increases the mobility of these metals. Particularly, Cd adsorption capacity in multi-metal conditions was significantly reduced. Overall, the results suggested that competitive adsorption studies are necessary for obtaining an accurate estimation of the metal retention capacity of pepper stem biochar in natural environments.
| Original language | English |
|---|---|
| Pages (from-to) | 617-632 |
| Number of pages | 16 |
| Journal | Archives of Agronomy and Soil Science |
| Volume | 62 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 2016 Jan 1 |
| Externally published | Yes |
Keywords
- Competitive adsorption
- Freundlich isotherm
- Langmuir isotherm
- Pepper stem biochar
ASJC Scopus subject areas
- Agronomy and Crop Science
- Soil Science