Investigation the effects of Al-grafting and calcination temperature on acidity and physicochemical properties of silica SBA-15
In this study, the effect of calcination temperature and Si/Al mole ratio on acidity and physicochemical properties of silica SBA-15 were investigated. Silica SBA-15 samples were calcined at 350, 450 and 550°C, and then post-synthesis, the Al-grafting method was applied to incorporate aluminum speci...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Serbian Chemical Society
2020-01-01
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| Series: | Journal of the Serbian Chemical Society |
| Subjects: | |
| Online Access: | http://www.doiserbia.nb.rs/img/doi/0352-5139/2020/0352-51392000021O.pdf |
| Summary: | In this study, the effect of calcination temperature and Si/Al mole ratio on acidity and physicochemical properties of silica SBA-15 were investigated. Silica SBA-15 samples were calcined at 350, 450 and 550°C, and then post-synthesis, the Al-grafting method was applied to incorporate aluminum species into their framework with Si/Al mole ratio of 10 and 30. Characterizations using small angle XRD and N2 adsorption–desorption techniques indicated that the hexagonal mesoporous structure was retained after performing Al-grafting even at the high aluminum loading. Moreover, FTIR results implied that the aluminum species were incorporated into the SBA-15 framework. NH3-TPD results showed that by decreasing Si/Al mole ratio at all calcination temperatures, the number of weak acid sites increased in comparison to those of the pure SBA-15 samples. Additionally, the maximum total acidity of synthesized samples was observed at the calcination temperature of 450°C with Si/Al mole ratio of 30. |
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| ISSN: | 0352-5139 1820-7421 |