Studies on dispersion and reactivity of vanadium oxides deposited on lamellar ferrierite zeolites for condensation of glycerol into bulky products
MetadataShow full item record
The acetalization of acetone with glycerol was investigated using vanadium-impregnated catalysts. The siliceous supports FER, a purely microporous material, and ITQ-6, a micro/mesoporous material, were obtained from a ferrierite lamellar precursor, PreFER. Both supports were impregnated with 1, 5 or 10 wt.% of vanadium. The structural properties were characterized by X-ray diffraction and N2 adsorption/desorption, the dispersion and speciation of surface vanadium were analyzed by diffuse reflectance UV–vis spectroscopy and X-ray absorption spectroscopy (XANES and EXAFS), and the total acidities of the catalysts were evaluated by temperature-programmed NH3 desorption. The [5V]Si-ITQ-6 and [10V]Si-ITQ-6 catalysts provided the best catalytic results, with conversions of 100 and 90%, respectively, and selectivity towards solketal of approximately 99%. The higher surface area generated by mesoporosity in the Si-ITQ-6 support, compared to the microporous Si-FER support, provided good access for the diffusion of reactants and products, and good dispersion of vanadium, even at high vanadium loadings (10 wt.%), with preferential formation of VO4 monomers and VOx oligomers on the surface. The greater contributions of these species to the total acidities of the catalysts resulted in higher catalytic activities, compared to the effect of V2O5 agglomerates.
How to cite this document
Showing items related by title, author, creator and subject.
Pinho, Sheila Zambello de ; Oliveira, José Brás Barreto de ; Gazola, Rodrigo José Cristiano ; Mazotti, Adriano César ; Molero, Camila Schimite ; Mendes, Carolina Borghi ; Mello, Denise Fernandes de ; Marques, Emilia de Mendonça Rosa ; Talamoni, Jandira Liria Biscalquini ; Silva, José Humberto Dias da et al. (Coleção PROGRAD (UNESP), 2011) [Livro]
Pinho, Sheila Zambello de ; Oliveira, José Brás Barreto de ; Pontes, Sueli Rodrigues ; Almeida, Djanira Soares de Oliveira e ; Godoy, Kathya Maria Ayres de ; Rosa, Claudia de Souza ; Nunes, Julianus Araújo ; Salvador, Sérgio Azevedo ; David, Célia Maria ; Vilche Peña, Angel Fidel et al. (Coleção PROGRAD (UNESP), 2011) [Livro]
Pinho, Sheila Zambello de ; Spazziani, Maria de Lourdes ; Mendonça, Sueli Guadelupe de Lima ; Rubo, Elisabete Aparecida Andrello ; Villarreal, Dalva Maria de Oliveira ; Duarte, Camila ; Okamoto, Mary Yoko ; Souza, Thais R. ; Garms, Gilza Maria Zauhy ; Marin, Fátima Aparecida Dias Gomes et al. (Coleção PROGRAD (UNESP), 2012) [Livro]