Phosphotungstic acid encapsulated in metal-organic framework UiO-66: An effective catalyst for the selective oxidation of cyclopentene to glutaraldehyde
| Autor: | Wei-Lin Dai, Li-Ming Qiao, Xin-Li Yang |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Terephthalic acid
Inorganic chemistry General Chemistry Condensed Matter Physics Catalysis chemistry.chemical_compound Adsorption chemistry Mechanics of Materials Cyclopentene General Materials Science Metal-organic framework Glutaraldehyde Lewis acids and bases Phosphotungstic acid Nuclear chemistry |
| Zdroj: | Microporous and Mesoporous Materials. 211:73-81 |
| ISSN: | 1387-1811 |
| DOI: | 10.1016/j.micromeso.2015.02.035 |
| Popis: | A heterogenous Zr-based metal organic framework (UiO-66) encapsulating phosphotungstic acid (HPWs) catalyst (HPWs@UiO-66), was prepared by a simple direct hydrothermal reaction of ZrCl 4 , terephthalic acid, and HPWs in DMF. The as-prepared novel material was very active as the catalyst for the selective oxidation of cyclopentene (CPE) to glutaraldehyde (GA) with environmentally benign hydrogen peroxide as the oxidant. The crystal structure and morphology of UiO-66 were well preserved after the incorporation of HPWs, as confirmed by X-ray diffraction (XRD), SEM, and TEM. Moreover, the XRD, N 2 adsorption, and FT-IR analyses reveal that HPW components could stably exist in the nanocages of UiO-66. FT-IR-CO adsorption experiments indicated that additional Lewis acid sites were present in the HPWs@UiO-66 sample, which were essential to catalyze the selective oxidation of CPE to GA. A proper amount of HPWs and their high dispersion accounted for high catalytic activity. Almost complete conversion of CPE (∼94.8%) and high yield of GA (∼78.3%) were obtained using the 35 wt% HPWs@UiO-66 catalyst. Furthermore, HPW components hardly leached in the reaction solution, enabling the catalyst to be used for three reaction cycles without obvious deactivation. |
| Databáze: | OpenAIRE |
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