One step transesterification of biodiesel production using simultaneous cooling and microwave heating.

Biofuel from marine microalgae is an attractive green sustainable product because marine microalgae absorb greenhouse gases (GHG) such as carbon dioxide during photosynthesis and microalgae based biofuel are free from sulphur during fuel combustion. The main obstacle for biodiesel production from marine microalgae is the high cost due to many downstream stages involved such as harvesting, dewatering, drying, extraction, separation and transesterification processes. In order to address these issues, the one step process is introduced where lipids are directly extracted and transesterified from wet biomass and processed using simultaneous cooling and microwave heating transesterification (SCMH) which is a green technology since microwave heating consumes only one third of the conventional heating energy and the cooling effect promotes more microwave penetration to the reaction mixture. This one step biodiesel production via SCMH was then benchmarked against the conventional one step process using the water bath heating and microwave assisted transesterification. The results revealed one step SCMH produced higher biodiesel production (75%) than water bath (13.46%) and microwave method (15.39%). The biodiesel production via SCMH was almost 5 times higher than the other methods. Biodiesel properties and cell disruption produced from SCMH method were also better than the other two methods. [ABSTRACT FROM AUTHOR]