Production of Bio-oil from Algal Biomass and Its Up-gradation: Recent Developments

Abstract

Algae, particularly microalgae are getting strong ground as a potential and environment friendly feedstock for biodiesel production in recent years due to its high growth rate (biomass yield) and high lipid content in some species. In the present paper the potential of algae as a feedstock for bio-oil production has been described. Mechanistic approach and optimum conditions for the algal growth as well as bio-oil production has been explained. Performance of various types of photo bioreactors has been critically analyzed to select suitable route for algal growth. Conventional methods such as mechanical and chemical extraction processes for the production of bio-oil form algal biomass have been described along with recent developments including supercritical extraction and microwave assisted processes. Various processes and catalysts for the up-gradation of bio-oil to biodiesel along with recent developments have also been described and compared. Effects of catalyst properties on the up-gradation of bio-oil have been critically analyzed for designing more efficient catalyst and consequently to improve the efficiency of the up-gradation process. Production of drop-in bio-fuel through hydrotreating of bio-oil is described. World scenario on the production of bio-fuel from algal biomass has also been provided.