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We investigated the nature of coke generated in propane dehydrogenation over supported Pt catalysts by FTIR, NMR, and XPS. NMR and FTIR spectra proved that the coke produced in the reaction contained poly-aromatic rings, which was consistent with the previous result that pregraphite-like coke structure was formed. The XPS results indicated that the coke deposits consisted of sp 2 hybridized carbon. All of the characterizations indicated that the pregraphite-like coke containing the poly-aromatic ring structure was generated over the catalysts during the propane dehydrogenation. Furthermore, the XPS measurement demonstrated that the coke deposits interacted with Pt and the electron density of Pt was enriched through the interaction.

One-dimensional titania nanomaterials were synthesized by soft chemical processes in an alkali medium. The effect of alkali-treatment temperature on the morphology, porosity, and crystalline phase of TiO 2 nanomaterials was investigated. Nanotubes having an opening end were observed when aging the sample at 130°C, while conducting the process at 180°C resulted in nanoribbons with a high aspect ratio. Post-treatment at 300°C led to the partial transformation from tubular structures into nanoparticles or ribbons into nanobelts. While the monoclinic sodium hexatitanate and anatase crystal had a tubular structure, nanoribbons and nanobelt TiO 2 also showed the presence of hydrogen titanate and sodium trititanate. High surface areas were achieved in as-prepared nanotubes and nanoribbons, 456.5 and 72.1 m 2 /g, respectively, and a drastic reduction was obtained upon post-treatment at 300°C to 72.1 and 19.2 m 2 /g, respectively.