Synthesis of Glycidol by Decarboxylation of Glycerol Carbonate Over Zn-La Catalysts with Different Molar Ratio

Abstract

Zinc-Lanthanum (Zn-La) mixed oxides are prepared with different molar ratios and used as catalysts for the synthesis of glycidol by decarboxylation of glycerol carbonate. The prepared catalysts were characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), N-2 adsorption-desorption and NH3/CO2 thermal programmed desorption (TPD) methods. The XRD patterns show that Zn-La mixed oxide exhibit both ZnO and La2O3 phases, mixed metal oxides are better in terms of specific surface area and porosity compared to pure metal oxide. From the TPD results, it observed that the ratio of acid/base site on the prepared catalyst is closer to 1 with increase of La molar. The catalytic performance of Zn-La catalysts was strongly dependent on their molar ratio; the highest glycidol yield was observed 76.22% with Zn/La = 1/9 catalyst. Above these results, acidic and basic properties of prepared catalyst were considered to play an important role in the synthesis of glycidol by decarboxylation of glycerol carbonate.