Investigation the effects of Al-grafting and calcination temperature on acidity and physicochemical properties of silica SBA-15
| Autor: | Orouj Reza, Rashidzadeh Mehdi, Irandoukht Akbar, Sadighi Sepehr |
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| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: | |
| Zdroj: | Journal of the Serbian Chemical Society, Vol 85, Iss 10, Pp 1345-1356 (2020) |
| Druh dokumentu: | article |
| ISSN: | 0352-5139 1820-7421 |
| DOI: | 10.2298/JSC191129021O |
| Popis: | 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. |
| Databáze: | Directory of Open Access Journals |
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