Abstract
The stability of MCM-48 was investigated as a function of pH. The material was treated with aqueous solutions of varying pH and the stability was determined by comparison with the untreated MCM-48. In acidic conditions of pH<5.4, the MCM-48 structure was stable and the BET surface area remained high (>1000 m2g-1), while the mean pore diameter decreased by approximately 20%. In neutral conditions, this phase was completely removed, characterised by the absence of an X-ray diffraction pattern and a dramatic reduction in surface area to 450 m2g-1 at pH 6.9. Treatment at pH 9.1 caused a transformation to a poorly ordered material, while further increased basic conditions caused significant structural collapse.
Original language | English |
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Pages (from-to) | 53-57 |
Number of pages | 5 |
Journal | Microporous and Mesoporous Materials |
Volume | 63 |
Issue number | 1-3 |
DOIs | |
Publication status | Published - 18 Sep 2003 |
Keywords
- Aqueous stability
- MCM-48
- Mesoporous
- PH