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Updated: Jan 24, 2026
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Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials
Published on: May 15, 2015
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Porous sound-absorbing materials prepared from fly ash
Liqiang Qi1,2, Jun Xu3, Kunyang Liu3
1Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control, Department of Environmental Science and Engineering, North China Electric Power University, Baoding, 071003, People's Republic of China. qiliqiang@ncepu.edu.cn.
Summary
Modified fly ash was used to create porous sound-absorbing materials. Optimal conditions yielded materials with good density, strength, porosity, and sound absorption, particularly at low frequencies.
Area of Science:
- Materials Science
- Acoustics Engineering
Background:
- Fly ash utilization in sustainable material development.
- Need for effective porous sound-absorbing materials.
Purpose of the Study:
- Investigate modified fly ash for porous sound-absorbing materials.
- Determine optimal preparation conditions for enhanced acoustic properties.
Main Methods:
- Modification of fly ash.
- Sintering at varying temperatures and times.
- Compression molding under different pressures.
Main Results:
- Achieved average volume density of 0.93 g/cm³.
- Compressive strength reached approximately 1.2 MPa with nearly 60% porosity.
- Average sound absorption coefficient reached 0.353 (low frequency) and 0.458 (overall).
Conclusions:
- Modified fly ash is suitable for porous sound-absorbing materials.
- Optimal conditions: 1100°C sintering for 5h, 2 MPa molding pressure.
- The developed material exhibits promising acoustic performance.
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