Glycerol dehydration catalyzed by MWW zeolites and the changes inthe catalyst deactivation caused by porosity modification
| Autor: | Teresita Francisca Garetto, Leandro Martins, Mariana Veiga Rodrigues, Celso Valentim Santilli, Sandra Helena Pulcinelli, Charito Ivana Vignatti |
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| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Process Chemistry and Technology
Inorganic chemistry Infrared spectroscopy MWW ZEOLITES DELAMINATION Microporous material INGENIERÍAS Y TECNOLOGÍAS Catalysis Ingeniería Química chemistry.chemical_compound chemistry PILLARIZATION Chemisorption Pyridine Otras Ingeniería Química Lewis acids and bases DEACTIVATION Mesoporous material Zeolite GLYCEROL DEHYDRATION |
| Popis: | Members of the layered MWW family, including microporous MCM-22, pillared MCM-36 and delaminated ITQ-2 zeolites, were used as catalysts for the gas phase dehydration of glycerol. The chemical, structural and surface properties of the catalysts were characterized by X-ray diffraction, N2 adsorption–desorption isotherms, SEM, TEM, NH3-TPD and pyridine chemisorption followed by IR spectroscopy. The results clearly showed that the modified zeolites with designed mesopore structure enabled rapid diffusion and consequently improved the glycerol conversion. Characterization of the acid sites revealed that the relative abundance of Brønsted and Lewis acid sites influenced the efficiency of the catalysis performed by these materials. 13C NMR spectra of the spent catalysts confirmed that differences in the nature and amount of carbonaceous deposits are related to the pore structures of the catalysts, with greater formation of polyaromatic compounds inside zeolite pores, while polyglycols are preferentially formed at the external surfaces of the MCM-36 and ITQ-2 zeolites, as expected for the more exposed sheets. Fil: Rodrigues, Mariana V.. Instituto de Química de Araraquara (UNESP); Brasil Fil: Vignatti, Charito Ivana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Garetto, Teresita Francisca. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica ; Argentina Fil: Pulcinelli, Sandra H.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil Fil: Santilli, Celso V.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil Fil: Martins, Leandro. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil |
| Databáze: | OpenAIRE |
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