Fe<sub>3</sub>O<sub>4</sub>/Mulberry Stem Biochar as a Potential Amendment for Highly Arsenic-Contaminated Paddy Soil Remediation
Magnetite-loaded biochar has recently received attention owing to its ability to remove arsenic from contaminated soil. In this study, mulberry stem biochar (MBC) and Fe<sub>3</sub>O<sub>4</sub>-loaded mulberry stem biochar (Fe<sub>3</sub>O<sub>4</sub>...
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-10-01
|
| Series: | Toxics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2305-6304/12/11/765 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Magnetite-loaded biochar has recently received attention owing to its ability to remove arsenic from contaminated soil. In this study, mulberry stem biochar (MBC) and Fe<sub>3</sub>O<sub>4</sub>-loaded mulberry stem biochar (Fe<sub>3</sub>O<sub>4</sub>@MBC) were produced and used in a 100-day incubation experiment to investigate their performance in the stabilization of arsenic in paddy soil severely polluted by the As (237.68 mg·kg<sup>−1</sup>) mechanism. Incubation experiments showed that Fe<sub>3</sub>O<sub>4</sub>@MBC was more effective in immobilizing As after incubation for 100 days. Moreover, adding Fe<sub>3</sub>O<sub>4</sub>@MBC facilitated the transformation of exchangeable heavy metals into organic-bound and residual forms, thereby reducing As available concentrations, mobility, and bioavailability in the soil, and elevating slightly the soil pH and dissolved organic carbon (DOC). The concentration of TCLP-extractable As (As<sub>TCLP</sub>) in contaminated soil was reduced from 93.85 to 7.64 μg·L<sup>−1</sup> within 10 d, below the safety limit for drinking water set by the World Health Organization (WHO). The characterization results of Fe<sub>3</sub>O<sub>4</sub>@MBC after incubation indicated that the mechanisms for As passivation are linked to redox reactions, complexation, electrostatic attraction, surface adsorption, and coprecipitation. Conclusively, Fe<sub>3</sub>O<sub>4</sub>@MBC is a promising amendment in highly As-contaminated soil and provides a theoretical reference in such polluted paddy soil remediation. |
|---|---|
| ISSN: | 2305-6304 |