Summary: | 碩士 === 元智大學 === 化學工程研究所 === 88 === In this study, benzene adsorption and reaction were examined over oxide support and supported Pt catalysts surface under atmopsperic pressure and 323K. The built-in-lab system is a flow-type adsorption system. Mass spectrometer was used for uptake detection, based on m/z=78.
Only irreversible adsorption was observed over Pt powder , TiO2 , Pt/ TiO2 where benzene adsorption partial pressure was below 30torr . Concurrent dehydrogenation were observed in all sample , but seemed more severe over Pt powder and Pt/ TiO2 . Based on the estimated monolayer coverages, the calculated cross sectional area were much smaller than van der Walls cross sectional area of benzene; therefore, this indicates that benzene adsorption over these sample is not lying flat.
The pretreatment was found to affect the benzene uptake over TiO2 and Pt/ TiO2,which follows LTR>C/LTR>HTR. The TOF of benzene hydrogenation over Pt/ TiO2 followed the same sequence as benzene uptake .This suggest benzene uptake over Pt/ TiO2 affects the hydrogenation activity over Pt/ TiO2.
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