One-step conversion of algal biomass to biodiesel with formation of an algal char as potential fertilizer

Abstract

We describe a new procedure for conversion of algal biomass into biodiesel using a single step process through the use of tetramethylammonium hydroxide (TMAH). The dried algae is placed in a laboratory-scale reactor with TMAH reagent (25% in methanol) under a blanket of flowing nitrogen gas and converted to a condensable gas-phase product (biodiesel) at temperatures ranging from 250 to 550°C. The condensed biodiesel is freed of methanol and analyzed by gas chromatography/mass spectrometry. Fatty acid methyl esters (FAME) are the main products of the reaction at all temperatures studied. Residues from the one-step conversion exhibit varying levels of transformation which may likely affect their end use.