Related Experiment Video
Updated: May 20, 2025
09:39
Physical, Chemical and Biological Characterization of Six Biochars Produced for the Remediation of Contaminated Sites
Published on: November 28, 2014
35.0K
Properties of Sunflower Straw Biochar Activated Using Potassium Hydroxide
Siyu Chang1,2, Lei Wang1, Lihong Yao1,2
1College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China.
Molecules (Basel, Switzerland)
|March 27, 2025
Summary
Sunflower straw biochar activated with potassium hydroxide (KOH) yields a material with enhanced surface area and structural properties. This optimized biochar preparation method improves aromaticity and graphitization for broader applications.
Area of Science:
- Materials Science
- Chemical Engineering
- Environmental Science
Background:
- Biochar, a carbon-rich material from biomass, is gaining attention due to its abundance and low cost.
- Potassium hydroxide (KOH) is an effective activator for modifying biochar's surface chemistry and microstructure.
- KOH-activated biochar exhibits a large specific surface area (SSA) and developed pore structure.
Purpose of the Study:
- To investigate the preparation of sunflower straw biochar activated by KOH.
- To analyze the effects of synthesis conditions on biochar performance and structure.
- To optimize KOH activation parameters for sunflower straw biochar.
Main Methods:
- Sunflower straw was used as the raw material.
- Potassium hydroxide (KOH) was employed as the activation agent.
- Characterization techniques included SEM, FTIR, XRD, XPS, and Raman spectroscopy.
Main Results:
- Optimal activation conditions identified: impregnation ratio of 2:1, activation time of 2 hours, and activation temperature of 900 °C.
- Scanning Electron Microscopy (SEM) revealed a rougher surface morphology in the activated biochar.
- Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy indicated increased aromaticity and graphitization.
Conclusions:
- The study successfully prepared KOH-activated sunflower straw biochar with improved structural characteristics.
- The optimized activation process enhances key properties of biochar, making it suitable for wider applications.
- Comprehensive analysis provides a foundation for the large-scale utilization of biochar materials.
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