Biochar Surface Chemistry Modification by Blending Hardwood, Softwood, and Refuse-Derived Fuel: Insights from XPS, FTIR, and Zeta Potential Analysis
Abstract
1. Introduction
2. Materials and Methodology
2.1. Biochar Preparation
2.2. Surface and Electrochemical Characterization
2.2.1. X-Ray Photoelectron Spectroscopy (XPS)
2.2.2. FTIR Spectroscopy
2.2.3. pH Measurement
2.2.4. Zeta Potential and Electrophoretic Mobility
3. Results and Discussion
3.1. Surface Elemental Composition and Chemical State Analysis Using XPS
3.2. Functional Group Characterization Using FTIR Spectroscopy
3.3. Electrostatic Surface Behavior and Colloidal Stability Assessments Using Zeta Potential and Electrophoretic Mobility
3.4. Influence of RDF Inclusion on Biochar Alkalinity and Surface pH Characteristics
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
Correction Statement
References
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Element | HW Weight % | HW/SW Weight % | HW/SW/RDF Weight % |
---|---|---|---|
N1s | 0.164481 | 0.240593 | 0.903234 |
C1s | 81.07511 | 82.45155 | 82.57513 |
O1s | 15.7526 | 13.02327 | 13.36913 |
Ca2p | 1.224915 | 2.067382 | 2.271619 |
Si2p | 0.374155 | 0.109751 | 0.685372 |
K2p | 1.408742 | 2.107454 | - |
Cl2p | - | - | 0.195517 |
Sample | Mean Zeta Potential (mV) | Electrophoretic Mobility (μm.cm/V·s) | pH | Electrochemical Conductivity (μs/cm) |
---|---|---|---|---|
HW | −31.5 ± 0.53 | −2.4567 | 10.10 | 113 ± 0.123 |
HW/SW | −30.0 ± 0.64 | −2.3385 | 10.25 | 170 ± 0.115 |
HW/SW/RDF | −24.2 ± 0.92 | −1.8875 | 7.76 | 53 ± 0.172 |
Biochar Sample | pH Range | Initial Zeta Potential (mV) | Final Zeta Potential (mV) |
---|---|---|---|
HW | 9–13 | −34 | −38 |
HW/SW | 9–13 | −44 | −30 |
HW/SW/RDF | 8–13 | −12.5 | −23 |
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Ani, P.C.; Al-Abedi, H.J.; Smith, J.D.; Zeitoun, Z. Biochar Surface Chemistry Modification by Blending Hardwood, Softwood, and Refuse-Derived Fuel: Insights from XPS, FTIR, and Zeta Potential Analysis. Fuels 2025, 6, 71. https://doi.org/10.3390/fuels6030071
Ani PC, Al-Abedi HJ, Smith JD, Zeitoun Z. Biochar Surface Chemistry Modification by Blending Hardwood, Softwood, and Refuse-Derived Fuel: Insights from XPS, FTIR, and Zeta Potential Analysis. Fuels. 2025; 6(3):71. https://doi.org/10.3390/fuels6030071
Chicago/Turabian StyleAni, Paul C., Hasan J. Al-Abedi, Joseph D. Smith, and Zeyad Zeitoun. 2025. "Biochar Surface Chemistry Modification by Blending Hardwood, Softwood, and Refuse-Derived Fuel: Insights from XPS, FTIR, and Zeta Potential Analysis" Fuels 6, no. 3: 71. https://doi.org/10.3390/fuels6030071
APA StyleAni, P. C., Al-Abedi, H. J., Smith, J. D., & Zeitoun, Z. (2025). Biochar Surface Chemistry Modification by Blending Hardwood, Softwood, and Refuse-Derived Fuel: Insights from XPS, FTIR, and Zeta Potential Analysis. Fuels, 6(3), 71. https://doi.org/10.3390/fuels6030071