Ultrasonication‐assisted transesterification for biodiesel production by using heterogeneous ZnO nanocatalyst

Biodiesel is considered as an alternative fuel which can replace the traditional fuels easily with its less hazardous effects and economical pricing. This study compares an ultrasonic‐assisted catalytic transesterification using ZnO nanocatalyst for waste cooking oil (WCO) with the conventional stirring method. The structural and morphological characterizations of prepared catalysts were done by XRD and FESEM with EDX methods. The effect of reaction parameters such as oil to methanol ratio, catalyst amount and reaction time was investigated to optimize the transesterification conditions. GC/MS and FTIR analysis have been carried out to identify and confirm the presence of fatty acid methyl esters (FAME) under optimum conditions. The FAME conversion yield up to 96% under ultrasonication method was calculated. Two important fuel properties like density and viscosity were analyzed and compared with the standard biodiesel. These studies provided the clear evidence that WCO can be employed as a substantial source of biodiesel as fuel in diesel engines. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1176–1182, 2018