Authors: Didem Özçimen and Benan İnan

In this study, biodiesel production from microalgal oil by microwave-assisted transesterification was carried out to investigate its efficiency. Transesterification reactions were performed by using Chlorella protothecoides oil as feedstock, methanol, and potassium hydroxide as the catalyst. Methanol:oil ratio, reaction time and catalyst:oil ratio were investigated as process parameters affected methyl ester yield. 9:1 methanol/oil molar ratio, 1.5% KOH catalyst/oil ratio and 10 min were optimum values for the highest fatty acid methyl ester yield.

Today, microalgae play an important role for the worldwide biofuel demand, together with the production of high value-added products used in pharmaceutical, nutraceutical and cosmetic industries. In 2014, the European Union adopted a strategy for developing the bioeconomy, by utilizing microalgae which represent an emerging biological resource of great importance for its potential applications in different fields. Huge potential of tiny microalgae could support a microalgae-based biorefinery and microalgae-based bioeconomy opening up vast opportunities in the global algae business. Nevertheless, in spite of having been studied for over 50 years now, there are still only just a few corporations that are cultivating algae on a large or commercial scale due to operational and capital cost. Techno-economic modeling is a powerful tool for guiding research priorities and assessing the economics, environmental impact and sustainability of microalgal productions. In this chapter, microalgal productions are assessed within bioeconomical aspects and case-studies on microalgal biorefinery are discussed.