A review on microwave-assisted biodiesel production

Different technologies have been employed for biodiesel production among which the application of microwaves has been found very promising. Microwaves are a part of electromagnetic waves between the radio frequency and infrared frequency ranges. In terms of power consumption, microwaves are relatively more efficient than conventional heating methods used for biodiesel production. Various parameters could affect microwave-assisted biodiesel production, including catalyst type and concentration, microwave power, reaction temperature, type of alcohol and alcohol-to-oil molar ratio, free fatty acids and water contents of oil as well as stirring rate. Therefore, it is necessary to obtain an in-depth understanding about the impacts of these parameters on biodiesel production process. This would be in achieving optimal values of these parameters and consequently enhanced reaction efficiencies could be achieved. According to the published literature, homogenous basic catalysts and higher microwave powers as well as elevated temperatures and alcohol contents could result in enhanced biodiesel production. This review present and critically discusses these parameters while also looks into the combination of microwave technology with other methods such as ultrasonication for improved biodiesel production.