Abstract: As the demand for biofuels increases globally, micro-algae offer a viable biomass in rural communities these materials could be converted to biodiesel. A one-step process was applied to directly converting wet oil-bearing micro-algae biomass of Chlorella pyrenoidosa containing about 90% of water into biodiesel. In order to investigate the effects of water content on biodiesel production, distilled water was added to dried micro-algae biomass to form wet biomass used to produce biodiesel. The results showed that at lower temperature of 90∘C, water had a negative effect on biodiesel production. The biodiesel yield decreased from 91.4% to 10.3% as water content increased from 0% to 90%. Higher temperature could compensate the negative effect. When temperature reached 150∘C, there was no negative effect, and biodiesel yield was over 100%. Based on the above research, wet micro-algae biomass was directly applied to biodiesel production, and the optimal conditions were investigated. Under the optimal conditions of 100 mg dry weight equivalent wet micro-algae biomass, 4 ml methanol, 8 ml n-hexane, 0.5 M H SO , 120∘C, and 180 min reaction time, the biodiesel yield reached. As high as 92.5% and the FAME content was 93.2%. The results suggested that biodiesel could be effectively produced directly from wet micro-algae biomass and this effort may offer the benefits of energy requirements for biodiesel production.

Keywords: Micro-algae biomass, Chlorella pyrenoidosa, Biodiesel yield.

| DOI: 10.17148/IARJSET.2021.8545