Diatomite-based porous ceramics with high apparent porosity: Pore structure modification using calcium carbonate
| Autor: | Xianglei Liu, Yulong Ding, Daqiang Cang, Zhu Jiang, Lingling Zhang, Yimin Xuan, Feng Jiang, Chuan Li |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Materials science
02 engineering and technology engineering.material 01 natural sciences Wollastonite chemistry.chemical_compound Larnite Specific surface area 0103 physical sciences Materials Chemistry Ceramic Composite material Porosity 010302 applied physics Process Chemistry and Technology 021001 nanoscience & nanotechnology Cristobalite Surfaces Coatings and Films Electronic Optical and Magnetic Materials Compressive strength Calcium carbonate chemistry visual_art Ceramics and Composites visual_art.visual_art_medium engineering 0210 nano-technology |
| Zdroj: | Ceramics International. 45:6085-6092 |
| ISSN: | 0272-8842 |
| Popis: | High apparent porosity ceramics have a wide range of applications in chemical, environmental, and automotive sectors as reactors, absorbers, and cleaning devices due to their large specific surface area and excellent permeability for fluids. In this paper, porous ceramics with high apparent porosity were successfully fabricated from diatomite. Importantly, the pore structure of this ceramic was further modified by calcium carbonate (CaCO3). The results showed that the pores of the modified ceramic were in the space between the loose particles, and the position originally occupied by the calcium carbonate. An addition of 0–50 wt% CaCO3 improved the apparent porosity up to 67.53% and enlarged the pore size from ~0.7 to ~26.6 µm due to the decomposition of CaCO3, generating new pores and further transforming isolated pores to interconnected ones. The crystalline phase composition of the ceramic was found to change from cristobalite to the combination of cristobalite, wollastonite and larnite with the addition of CaCO3. The results also showed that an addition of more than 40 wt% of CaCO3 did not give much further increase in the apparent porosity due to the densification process. The modified ceramics were found to have a good mechanical strength; the ceramic with the highest apparent porosity (67.53%) had a compressive strength of 7.33 ± 0.28 MPa. |
| Databáze: | OpenAIRE |
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