Oxidation of Glycerol with Oxygen Molecules as the Oxidant over Activated Clay Material Catalysts

Abstract

Interest in glycerol oxidation to more useful products has risen significantly over the years. This has led to the development of several catalysts some of which are scarce, uneconomical and environmentally unfriendly. In this research, two catalysts prepared from red earth - ‘A1’ (calcined at 500°c) and ‘A2’ (calcined at 500°c and dealuminated) were characterized using x-ray fluorescence (XRF) and used to oxidize glycerol with O2 molecules for 240 mins. The XRF results showed that Al2O3 (31.3%), SiO2 (47.9%) and Fe2O3 (16.05%) were the predominant components in ‘A1’ while ‘A2’ showed a marked significant difference in Al2O3 (19.4%), SiO2 (72.1 %) and Fe2O3 (0 %). The selectivities of the oxidation products with A1 were 18.8 % glyceric acid (GLA), 13.1 % lactic acid (LCA), 1.66 % oxalic acid (OXA) and 1.24 % formic acid (FMA), while for A2 they were (20.4%) GLA and (17%) LCA. 88.1% glycerol was converted but selectivity towards any of the products was low.