Single step synthesis of sulfonic group bearing graphene oxide: A promising carbo-nano material for biodiesel production

•Two different graphene oxides as IGO and MGO are synthesized.•The catalytic performance of IGO is found to be superior to that of the MGO.•The superior catalytic performance is due to the presence of more active acidic sites.•Biodiesel quality is compared with ASTM D6751 value.

Biodiesel is non-conventional and sustainable fuel. Till date various materials and methods were investigated for biodiesel production. In this study two different graphene oxides as IGO (Improved graphene oxide) and MGO (Modified graphene oxide) are synthesized and further explored in the esterification of oleic acid with methanol. The SO3H groups in graphene oxide are chiefly responsible for esterification. Different spectroscopic and non spectroscopic data reveal that SO3H groups are present in the thin layered graphene oxide leaves. The effect of various reaction parameters like reaction time, temperature, methanol to oleic acid ratio, catalyst amount and catalyst recycling were investigated. The kinetic studies of esterification have been carried out at three operating temperatures using IGO as a catalyst. The results revealed that the reaction followed pseudo first order kinetics in all tested temperature (70, 80 and 90 °C) and the activation energy was calculated to be 13 kJ mol−1. Various properties of as obtained biodiesel were determined and compared with the American Society for Testing and Materials (ASTM) standards.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide