Catalytic activity of niobia supported graphene oxide for esterification of oleic acid

Abstract

Biodiesel has been obtained from esterification of oleic acid with methanol using niobia loaded graphene oxide (GO). Different weight percentages of niobia (1, 3, 5 and 7 wt.%) have been loaded on GO by the wet impregnation method. The synthesized materials have been characterized by XRD, FT-IR, Raman spectroscopy, TGA, BET surface area, NH₃-TPD, ICP-OES, SEM and HR-TEM studies. The catalytic activity of niobia supported on GO has been tested for esterification of oleic acid with methanol for biodiesel production. The maximum yield of methyl oleate (96.4%) is obtained at the reaction conditions of 150 °C, 0.5 g of 5 wt% of niobia on GO catalyst, 1:9 molar ratio of oleic acid:methanol and time 4 h. Influence of solvents (ethanol, propanol, butanol) has been tested for comparative study with same reaction conditions. Based on the catalytic studies, niobia supported GO has good catalytic activity for esterification of oleic acid reaction with good reusability.