An analysis of the chemical, physical and reactivity features of MgO–SiO2 catalysts for butadiene synthesis with the Lebedev process. Issue 6 (9th November 2015)

• Record Type: Journal Article
• Authors: Ochoa, Juliana Velasquez; Bandinelli, Claudia; Vozniuk, Olena; Chieregato, Alessandro; Malmusi, Andrea; Recchi, Carlo; Cavani, Fabrizio
• Is Part Of: Green chemistry. Volume 18:Issue 6(2016)
• Page Start: 1653
• Page End: 1663
• Publication Date: 2015-11-09
• Subjects: Environmental chemistry -- Industrial applications -- Periodicals; Environmental management -- Periodicals; 660
• DOI: 10.1039/c5gc02194d
• Languages: English
• ISSNs: 1463-9262

Abstract

Abstract : In MgO–SiO2 catalysts for the transformation of bio-ethanol into butadiene, the generation of more selective sites is achieved by the dispersion of isolated Si 4+ atoms in MgO. Abstract : New insights into the transformation of ethanol to butadiene over MgO–SiO2 catalysts, prepared by means of the sol–gel technique, have been gained via characterization, catalytic tests, and in situ infrared diffuse reflectance spectroscopy. Catalysts with low Si-content, i.e., with a Mg/Si atomic ratio in the range between 9 and 15, gave superior butadiene yields, because of the proper combination of strong basic sites, required for ethanol activation, and a moderate number of medium-strength acid sites, needed for the dehydration of intermediately formed alkenols to butadiene. A model of the medium-strength, Lewis-type acid sites, consisting of Mg 2+ cations with neighbouring Si 4+ atoms, has been proposed; these sites are converted into Brønsted sites in the presence of water, a co-product of the multistep transformation of ethanol into C4 molecules.