PYROLYSIS OF ISOCHRYSIS MICROALGAE WITH METAL OXIDE CATALYSTS FOR BIO-OIL PRODUCTION

Abstract

Pyrolysis of Isochrysis microalga was carried out in a fixed-bed reactor without and with metal oxide catalysts (CeO2, TiO2, Al2O3) for the first time at the temperatures of 450, 500 and 550 °C with a constant heating rate of 40 °C/min. The pyrolytic conditions including catalyst and temperature were studied in terms of their effects on the yields of pyrolytic products and quality. The amounts of bio-char, bio-oil, and gaseous products were calculated. The composition of the produced bio-oils was determined by Elemental analysis (EA), Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1 H NMR) and Gas chromatography/mass spectrometry (GC-MS) techniques. As a result of the pyrolysis experiments, it is shown that there have been significant effects of both catalyst and temperature on the conversion of Isochrysis microalgae into solid, liquid (bio-oil) and gas products. The highest bio-oil yield (24.30 %) including aqueous phase was obtained in the presence of TiO2 (50%) as catalyst at 500 °C. 98 different compounds were identified by GC-MS in bio-oils obtained at 500 o C. According to 1 H NMR analysis, bio-oils contained ∼60-64% aliphatic and ∼17-19% aromatic structural units. EA showed that the bio-oils contained ∼66-69% C and having 31-34 MJ/kg higher heating values. Cite this: Aysu T. Pyrolysis of Isochrysis Microalgae with Metal Oxide Catalysts for Bio-Oil Production.