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Nafion-incorporated silicate structured nanocomposite mesoporous catalysts for dimethyl ether synthesis / Aysegul Ciftci in Industrial & engineering chemistry research, Vol. 49 N° 15 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 6753–6762 Titre : Nafion-incorporated silicate structured nanocomposite mesoporous catalysts for dimethyl ether synthesis Type de document : texte imprimé Auteurs : Aysegul Ciftci, Auteur ; Naime Asli Sezgi, Auteur ; Timur Dogu, Auteur Année de publication : 2010 Article en page(s) : pp 6753–6762 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Mesoporous  Catalysts  Ether  synthesis. Résumé : Being chemically and thermally stable, Nafion resin is considered to be an attractive solid acid catalyst. Although it has high acid strength and the ability to catalyze a wide range of reactions, the catalytic activity of Nafion is limited, because of its very low specific surface area. In this study, mesoporous Nafion−silica nanocomposites were developed by following a one-pot acidic hydrothermal synthesis procedure. Synthesized catalysts were determined to have well-dispersed structures with high surface area values (595−792 m2/g) and strong Brønsted, as well as Lewis, acid sites. The activities of these novel catalysts were tested in dimethyl ether synthesis from methanol in a flow system. The effects of modifications in the synthesis procedure and Nafion loading showed that the material synthesized from a solution containing a Nafion/silica weight ratio of 0.15 and refluxed with a 2 M sulfuric acid−ethanol (SAE) mixture for surfactant removal was the best catalyst for this reaction. Production of the green transportation fuel alternate dimethyl ether (DME) was achieved with this catalyst at very high yields with almost 100% DME selectivity at >180 °C. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015667 [article] Nafion-incorporated silicate structured nanocomposite mesoporous catalysts for dimethyl ether synthesis [texte imprimé] / Aysegul Ciftci, Auteur ; Naime Asli Sezgi, Auteur ; Timur Dogu, Auteur . - 2010 . - pp 6753–6762. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 15 (Août 2010) . - pp 6753–6762 Mots-clés : Mesoporous  Catalysts  Ether  synthesis. Résumé : Being chemically and thermally stable, Nafion resin is considered to be an attractive solid acid catalyst. Although it has high acid strength and the ability to catalyze a wide range of reactions, the catalytic activity of Nafion is limited, because of its very low specific surface area. In this study, mesoporous Nafion−silica nanocomposites were developed by following a one-pot acidic hydrothermal synthesis procedure. Synthesized catalysts were determined to have well-dispersed structures with high surface area values (595−792 m2/g) and strong Brønsted, as well as Lewis, acid sites. The activities of these novel catalysts were tested in dimethyl ether synthesis from methanol in a flow system. The effects of modifications in the synthesis procedure and Nafion loading showed that the material synthesized from a solution containing a Nafion/silica weight ratio of 0.15 and refluxed with a 2 M sulfuric acid−ethanol (SAE) mixture for surfactant removal was the best catalyst for this reaction. Production of the green transportation fuel alternate dimethyl ether (DME) was achieved with this catalyst at very high yields with almost 100% DME selectivity at >180 °C. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015667