Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral Composition
The reaction products resulting from the alkali-activation of metakaolin are impacted by the composition of the initial kaolin, and amount of alkali-activated kaolinite and water. The present study focused on analyzing these parameters on the metakaolins calcined at 800 °C from three kaolins, and th...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | Minerals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-163X/12/11/1342 |
| _version_ | 1797467189844901888 |
|---|---|
| author | Marta Valášková Zdeněk Klika Jozef Vlček Lenka Matějová Michaela Topinková Helena Pálková Jana Madejová |
| author_facet | Marta Valášková Zdeněk Klika Jozef Vlček Lenka Matějová Michaela Topinková Helena Pálková Jana Madejová |
| author_sort | Marta Valášková |
| collection | DOAJ |
| description | The reaction products resulting from the alkali-activation of metakaolin are impacted by the composition of the initial kaolin, and amount of alkali-activated kaolinite and water. The present study focused on analyzing these parameters on the metakaolins calcined at 800 °C from three kaolins, and the metakaolins’ alkali activation for 2, 3 and 28 days. The first objective was to evaluate the mineral chemistry and quantitative mineral phase composition from the bulk chemical analysis using the chemical quantitative mineral analysis (CQMA) procedure and conduct a comparison of the chemistry of the metakaolins after alkali activation for 28 days according to the elements Al, Si, Na and K, using the leaching test in distilled water. The second task was to search for possible relationships between the quantitative number of phases in alkali-activated metakaolins and compressive strength. The main methods used for the characterization of material were X-ray fluorescence, X-ray diffraction, thermal TG/DTA and infrared spectroscopy. Metakaolins alkali activated for 28 days contained crystalline quartz, muscovite, orthoclase, and unreacted metakaolinite contained zeolite A (Z-A), hydrosodalite (HS) and thermonatrite (TN) in the amorphous/weakly crystalline phase. The compressive strengths (CS) from 6.42 ± 0.33 to 9.97 ± 0.50 MPa are related positively to H<sub>2</sub>O+ and H<sub>2</sub>O bound in HS and TN. |
| first_indexed | 2024-03-09T18:49:06Z |
| format | Article |
| id | doaj.art-93cbc969f346420189b24ababdf0d072 |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-03-09T18:49:06Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Minerals |
| spelling | doaj.art-93cbc969f346420189b24ababdf0d0722023-11-24T05:57:52ZengMDPI AGMinerals2075-163X2022-10-011211134210.3390/min12111342Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral CompositionMarta Valášková0Zdeněk Klika1Jozef Vlček2Lenka Matějová3Michaela Topinková4Helena Pálková5Jana Madejová6Institute of Environmental Technology, CEET, VSB—Technical University of Ostrava, 17. listopadu 15/2172, 708 00 Ostrava, Czech RepublicDepartment of Chemistry and Physico-Chemical Processes, Faculty of Material Science and Technology, VSB—Technical University of Ostrava, 17. listopadu 15/2172, 708 00 Ostrava, Czech RepublicInstitute of Environmental Technology, CEET, VSB—Technical University of Ostrava, 17. listopadu 15/2172, 708 00 Ostrava, Czech RepublicInstitute of Environmental Technology, CEET, VSB—Technical University of Ostrava, 17. listopadu 15/2172, 708 00 Ostrava, Czech RepublicInstitute of Environmental Technology, CEET, VSB—Technical University of Ostrava, 17. listopadu 15/2172, 708 00 Ostrava, Czech RepublicInstitute of Inorganic Chemistry, Slovak Academy of Science, Dúbravská cesta 9, 845 36 Bratislava, SlovakiaInstitute of Inorganic Chemistry, Slovak Academy of Science, Dúbravská cesta 9, 845 36 Bratislava, SlovakiaThe reaction products resulting from the alkali-activation of metakaolin are impacted by the composition of the initial kaolin, and amount of alkali-activated kaolinite and water. The present study focused on analyzing these parameters on the metakaolins calcined at 800 °C from three kaolins, and the metakaolins’ alkali activation for 2, 3 and 28 days. The first objective was to evaluate the mineral chemistry and quantitative mineral phase composition from the bulk chemical analysis using the chemical quantitative mineral analysis (CQMA) procedure and conduct a comparison of the chemistry of the metakaolins after alkali activation for 28 days according to the elements Al, Si, Na and K, using the leaching test in distilled water. The second task was to search for possible relationships between the quantitative number of phases in alkali-activated metakaolins and compressive strength. The main methods used for the characterization of material were X-ray fluorescence, X-ray diffraction, thermal TG/DTA and infrared spectroscopy. Metakaolins alkali activated for 28 days contained crystalline quartz, muscovite, orthoclase, and unreacted metakaolinite contained zeolite A (Z-A), hydrosodalite (HS) and thermonatrite (TN) in the amorphous/weakly crystalline phase. The compressive strengths (CS) from 6.42 ± 0.33 to 9.97 ± 0.50 MPa are related positively to H<sub>2</sub>O+ and H<sub>2</sub>O bound in HS and TN.https://www.mdpi.com/2075-163X/12/11/1342alkali-activated metakaolinX-ray diffractionchemical quantitative phase analysisstability in watercompressive strength |
| spellingShingle | Marta Valášková Zdeněk Klika Jozef Vlček Lenka Matějová Michaela Topinková Helena Pálková Jana Madejová Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral Composition Minerals alkali-activated metakaolin X-ray diffraction chemical quantitative phase analysis stability in water compressive strength |
| title | Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral Composition |
| title_full | Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral Composition |
| title_fullStr | Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral Composition |
| title_full_unstemmed | Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral Composition |
| title_short | Alkali-Activated Metakaolins: Mineral Chemistry and Quantitative Mineral Composition |
| title_sort | alkali activated metakaolins mineral chemistry and quantitative mineral composition |
| topic | alkali-activated metakaolin X-ray diffraction chemical quantitative phase analysis stability in water compressive strength |
| url | https://www.mdpi.com/2075-163X/12/11/1342 |
| work_keys_str_mv | AT martavalaskova alkaliactivatedmetakaolinsmineralchemistryandquantitativemineralcomposition AT zdenekklika alkaliactivatedmetakaolinsmineralchemistryandquantitativemineralcomposition AT jozefvlcek alkaliactivatedmetakaolinsmineralchemistryandquantitativemineralcomposition AT lenkamatejova alkaliactivatedmetakaolinsmineralchemistryandquantitativemineralcomposition AT michaelatopinkova alkaliactivatedmetakaolinsmineralchemistryandquantitativemineralcomposition AT helenapalkova alkaliactivatedmetakaolinsmineralchemistryandquantitativemineralcomposition AT janamadejova alkaliactivatedmetakaolinsmineralchemistryandquantitativemineralcomposition |