One-pot synthesis of glycerol carbonate from glycerol using three-dimensional mesoporous silicates of K/TUD-1 under environmentally benign conditions

Abstract

In the present study, a series of potassium (K) incorporated three-dimensional mesoporous silica material (K/TUD-1) has been synthesized for the one-pot synthesis of glycerol carbonate through transesterification of glycerol with dimethyl carbonate (DMC). The synthesized catalyst (K/TUD-1) has been characterized to confirm porosity by nitrogen adsorption-desorption isotherm, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Small-angle XRD revealed that TUD-1 is mesostructure in nature. Morphology study revealed that TUD-1 exhibited a 3D structure without any agglomeration. The surface area of bare TUD-1 significantly declined with the incorporation of active metal from 632 m2/g to 430 m2/g. However, the basicity of K/TUD-1 improved, which is a highly desired property for the transesterification reaction. Batch experimental results have been concluded that 7% K/TUD-1 has better catalytic activity for the conversion of glycerol to glycerol carbonate. Further investigation has been conducted on the influence of reaction parameters such as reaction temperature, reaction time, catalyst dosage, and DMC/glycerol molar ratio. Under optimized conditions the maximum glycerol carbonate yield (∼91.50 %) was observed with catalyst dose of 6 wt.% (of glycerol mass), DMC/glycerol molar ratio of 5, reaction temperature of 90 °C in 2.5 h. Further, catalyst feasibility was also conducted at optimized conditions, and it sustains activity up to 4 cycles. The kinetics of the reaction was studied using the ODE 15 s solver in MATLAB.