Texture Properties of Undoped and NaO-doped VO/AlO, Catalysts
Pure alumina, V 2 O 5 –Al 2 O 3 and Na 2 O-doped V 2 O 5 /Al 2 O 3 samples have been obtained and roasted in air over the temperature range 400–750°C. The textural properties of all the calcination products have been determined from nitrogen adsorption studies at 77 K. The inclusion of V 2 O 5 in al...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
SAGE Publications
1995-03-01
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| Series: | Adsorption Science & Technology |
| Online Access: | https://doi.org/10.1177/026361749501200104 |
| Summary: | Pure alumina, V 2 O 5 –Al 2 O 3 and Na 2 O-doped V 2 O 5 /Al 2 O 3 samples have been obtained and roasted in air over the temperature range 400–750°C. The textural properties of all the calcination products have been determined from nitrogen adsorption studies at 77 K. The inclusion of V 2 O 5 in alumina modifies the textural characteristics leading to an enhancement of activation at temperatures ≤450°C and to an enhancement of sintering at higher temperatures. Furthermore, AlV 2 O 4 which formed at temperatures below 750°C resulted in a tremendous change in the textural properties. Three types of sintering were detected, i.e. particle-particle adhesion, pore widening and phase change. Doping with Na 2 O retards sintering and at low calcination temperatures gave solids with higher surface areas compared to undoped samples. This has been attributed to activation brought about by the decomposition of NaNO 3 and the evolution of nitrogen oxides. |
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| ISSN: | 0263-6174 2048-4038 |