Assessing the surface sites of the microporous materials H-ITQ-7 and H-Beta using FT-IR spectroscopy and various molecular probes
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- Institutt for kjemi 
The aim of the work presented in this thesis was to synthesize and assess the surface sites of two possible acid catalysts. The MTH reaction was used as a model reaction to evaluate the possibilities for the materials to act as catalysts in acid catalysed reactions. The catalysts, H-Beta and H-ITQ-7, were synthesized from raw materials, including the structure directing agent for the H-ITQ-7. Next, their structures were characterized by PXRD, SEM,BET, ICP-MS and TGA, in order to verify that the materials were consistent with literature. Finally, the materials were investigated in-situ by applying the combination of FT-IR spectroscopy and selected molecular probes (CO, H2O, CH3OH, NH3, pyridine, HMB, durene andC2H4). The different molecular probes give different information of the strength and characteristics of the structural surface sites. The acidic strength and density of the samples were found to be in good agreement with literature. This indicates that the samples possess strong acidity, and are suitable as acidic catalysts. The only exception seen was for the H-ITQ-7.1 sample when methanol and durene were used as molecular probes, where the sample showed no sign of acidity. To verify these results, some of the samples was tested as catalyst for the conversion of methanol to hydrocarbons. The investigated samples were demonstrated to be active as catalysts in acid catalysed reactions. The activity was found to be in proper agreement to similar catalysts in literature.