Search results for "2-Propanol dehydration"
showing 5 items of 5 documents
Keggin heteropolyacid supported on BN and C3N4: Comparison between catalytic and photocatalytic alcohol dehydration
2020
The Keggin heteropolyacid (HPA), H3PW12O40 (PW12) has been supported on commercial boron nitride (BN) and two types of home prepared carbon nitride (C3N4). The supported PW12 was used in the gas-solid (photo)catalytic 2-propanol dehydration reaction to give propene at atmospheric pressure and temperatures in the range 70–120 °C and resulted more active than the pristine PW12. Reaction rate increased by increasing the temperature. Noticeably, the propene formation rate was higher by irradiating the catalytic system. The PW12/BN material resulted more active than PW12/C3N4. The acidity of the HPA cluster accounts for the catalytic role, whereas both the acidity and the redox properties of the…
Supported H3PW12O40 for 2-propanol (photo-assisted) catalytic dehydration in gas-solid regime: The role of the support and of the pseudo-liquid phase…
2016
Abstract Catalytic and photocatalytic 2-propanol dehydration was carried out by using a supported Keggin heteropolyacid H3PW12O40 (PW12). Binary materials were prepared by impregnation and/or solvothermal treatment by using commercial supports: SiO2 (Mallinckrodt), TiO2 (Evonik P25) and multiwall carbon nanotubes (Sunnano) or home solvothermically prepared SiO2 and TiO2. All the materials have been characterized by X-ray diffraction (XRD), scanning electron microscopy observations (SEM) coupled with EDX microanalysis, specific surface area measurements, diffuse reflectance spectroscopy (DRS), FTIR and Raman spectroscopy. (Photo)catalytic 2-propanol dehydration was studied in gas-solid regim…
Enhanced (photo)catalytic activity of Wells-Dawson (H6P2W18O62) in comparison to Keggin (H3PW12O40) heteropolyacids for 2-propanol dehydration in gas…
2016
Abstract Catalytic and photocatalytic 2-propanol dehydration to propene at atmospheric pressure and a temperature range of 60–120 °C were carried out in gas-solid regime by using bare and supported Keggin H 3 PW 12 O 40 (PW 12 ) and Wells-Dawson H 6 P 2 W 18 O 62 (P 2 W 18 ) heteropolyacids (HPAs). Binary materials were prepared by impregnation of the HPAs on commercial SiO 2 and TiO 2 . The Wells-Dawson was in any case more active than the Keggin heteropolyacid and the differences were enhanced when the supported samples were used. In particular, Wells-Dawson HPA supported on TiO 2 and under irradiation showed the highest activity. The HPA species played the key role both in the catalytic …
Heteropolyacids supported on boron nitride and carbon nitride for catalytic and catalytic photo-assisted alcohol dehydration
2021
Keggin H3PW12O40 (PW12) and Wells-Dawson H6P2W18O60 (P2W18) heteropolyacids (HPAs) are photo(catalysts) for various acid-promoted and redox catalytic reactions. Their activity increases if they are deposited on certain supports as metal oxides or carbon materials. Although the surface area and acid-base interactions of the HPAs with supports are considered as key factors for the performance of the binary material, the role of the local structure changes in the HPAs upon their immobilization on solids must be also of primary importance, directly affecting both acidity and photoredox properties. Here, the (photo)catalytic performance of Keggin and Wells-Dawson heteropolytungstates supported o…
Keggin and Wells-Dawson supported heteropolyacids as heterogeneous (photo)catalysts for gas-solid 2-propanol dehydration
2016
Catalytic and photocatalytic tests for 2-propanol dehydration to propene were successfully carried out by using binary materials obtained by supporting a Keggin or Wells-Dawson heteropolyacids via impregnation method to commercial SiO2 or TiO2. (Photo)catalytic 2-propanol dehydration was studied in gas-solid regime by using a continuous (photo)reactor working at atmospheric pressure and 80 °C. Propene and diisopropyl ether were the main reaction products. For the continuous photo-assisted runs the reactor was also illuminated with UV light. The heteropolyacid species played a key role both for the catalytic and the photo-assisted catalytic reactions; indicating that the acidity of the clust…