Enviro-economical benign synthesis of glycerol carbonate from biowaste glycerol using industrial waste pond ash catalyst

The dramatic increase in biodiesel plant leads to oversupplied glycerol as its by product which requires industrial application for sustainability of biodiesel. The main focus of this study is the proper utilization of industrial waste pond ash for the preparation of various catalysts for the synthesis of glycerol carbonate . A series of catalysts were prepared by doping barium , lithium and potassium on the surface of pond ash collected from national thermal power plant (NTPC, Talcher, India). Among all the synthesized catalyst 20% Barium doped pond ash catalyst provided highest conversion of glycerol i.e. 98% and 94% glycerol carbonate yield respectively at mild reaction conditions. . 20% Ba doped pond ash catalyst was highly suitable for glycerol carbonate synthesis due to highest basic strength. The physicochemical properties of synthesized catalyst were studied through TGA-DSC, XRD, FT-IR spectra , SEM -EDX analysis . The catalytic performance as well as reaction parameters like temperature, time, DMC to glycerol molar ratio and catalyst loading percentage were optimized for better conversion of glycerol. Green metrics like E-factors , PMI are also studied to determine the sustainability and environmental impact of catalyst as well as transesterification reaction of glycerol. The overall evaluation of green chemistry for the work indicated that the synthesized catalyst is environmental benign in nature.