Gold nanoparticles supported on various oxides (CeO2, CeO2/TiO2, MgO, MgO/TiO2, La2O3, La2O3/TiO2) (with 4 wt.% Au loading) were investigated in the liquid (aqueous) phase oxidation of glycerol by molecular oxygen under mild conditions, in the presence of alkaline earth (CaO, SrO and MgO) or alkaline (NaOH) bases. Full conversion and selectivity between 38 and 68% to sodium glycerate were observed on different Au supported catalysts (Au/MgO/TiO2, Au/La2O3/TiO2, Au/CeO2 and Au/CeO2/TiO2). The combined effect of Au particle size and basicity of the support was suggested as the determining factor of the activity. Agglomeration of gold nanoparticles, found after the reaction, led to the deactivation of the catalysts, which prevents the further oxidation of sodium glycerate into sodium tartronate. Promising results were obtained with the use of alkaline earth bases (CaO, SrO, MgO), leading to the formation of free carboxylic acids instead of salts, which are formed in the presence of the more usual base, NaOH.
Glycerol Oxidation over Supported Gold Catalysts: The Combined Effect of Au Particle Size and Basicity of Support / E. Pakrieva, E. Kolobova, D. German, M. Stucchi, A. Villa, L. Prati, N. Bogdanchikova, V. Cortés Corberán, A. Pestryakov. - In: PROCESSES. - ISSN 2227-9717. - 8:9(2020 Aug 20).
|Titolo:||Glycerol Oxidation over Supported Gold Catalysts: The Combined Effect of Au Particle Size and Basicity of Support|
|Parole Chiave:||gold catalysts; glycerol oxidation; catalyst selectivity; glyceric acid; glycolic acid; tartronic acid; base additives|
|Settore Scientifico Disciplinare:||Settore CHIM/03 - Chimica Generale e Inorganica|
|Data di pubblicazione:||20-ago-2020|
|Data ahead of print / Data di stampa:||giu-2020|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.3390/pr8091016|
|Appare nelle tipologie:||01 - Articolo su periodico|