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http://hdl.handle.net/1843/45415
Tipo: | Artigo de Periódico |
Título: | Fe4(SiW12O40)3-catalyzed glycerol acetylation: synthesis of bioadditives by using highly active Lewis acid catalyst |
Autor(es): | Márcio José da Silva Natalia Aparecida Liberto Lorena Cristina de Andrade Leles Ulisses Alves Pereira |
Resumen: | In order to investigate the effect of Lewis acidic metals on the acid properties of Keggin heteropolyacids catalysts, a set of metal-exchanged HPAs (i.e. M3/nPW12O40, M3/nPMo12O40 and M4/nSiW12O40 (M = Cu, Co and Mn, n = 2; M = Fe, n = 3) were synthesized and their activity on glycerol esterification with acetic acid was evaluated. This procedure avoids the use of corrosive Brønsted acid catalysts. Regardless of the heteropoly anion, the activity of catalysts in terms of metal cations followed the sequence: Fe3+> Cu2+> Mn2+> Co2+. It has been found that among the HPAs, only H4SiW12O40 has the acidic protons that can be successfully exchanged with Fe3+ cations, resulting in Fe4(SiW12O40)3 salt, the most active and selective catalyst. The highest conversion (ca.99.9%) was achieved in Fe4(SiW12O40)3-catalyzed esterification reactions, along with the highest selectivity for di and triacetyl glycerol (ca.55 and 42%, respectively). Effects of temperature, stoichiometry of reactants, concentration and nature of catalysts were assessed. A kinetic study of Fe4(SiW12O40)3 or H4SiW12O40-catalyzed reactions was conducted and the activation energy determined. |
Asunto: | Glicerina Catalisadores Ésteres Ácido acético |
Idioma: | eng |
País: | Brasil |
Editor: | Universidade Federal de Minas Gerais |
Sigla da Institución: | UFMG |
Departamento: | ICA - INSTITUTO DE CIÊNCIAS AGRÁRIAS |
Tipo de acceso: | Acesso Restrito |
Identificador DOI: | https://doi.org/10.1016/j.molcata.2016.03.003 |
URI: | http://hdl.handle.net/1843/45415 |
Fecha del documento: | oct-2016 |
metadata.dc.url.externa: | https://www.sciencedirect.com/science/article/pii/S138111691630070X |
metadata.dc.relation.ispartof: | Journal of Molecular Catalysis A: Chemical |
Aparece en las colecciones: | Artigo de Periódico |
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