Comparison of Oils from the Low Temperature Pyrolysis of Algal Biomass and Bituminous Coal in a Rotary Kiln

Abstract

It is well known that the synthesis of liquid fuels via the pyrolysis of coal is associated with low yields rendering the process un-economic. On the other hand, significantly high yields are achievable via the pyrolysis of biomass. In this study, a comparison of the yields and composition of oils synthesized from the pyrolysis of Scenedesmus algal biomass and bituminous coal in a rotary kiln at 550 °C is performed. The yields of oil obtained were 6 and 40 % for coal and algal biomass, respectively. GCMS analysis revealed that the oil synthesized from coal was rich in paraffins, having 4.4 % oxygenated compounds, 31.7 % polycyclic aromatic hydrocarbons, 4.1 % nitrogen containing polycyclic aromatic hydrocarbons, 52.6 % paraffins and the rest being other compounds. On the other hand, oil from algal biomass was rich in fatty acid esters, containing 17.6 % alcohols, 10.8 % fatty acids, 28.8 % fatty acid esters, 6.2 % poly-cyclic aromatic hydrocarbons, 4.5 % nitrogen containing poly-cyclic aromatic hydrocarbons, 5.3 % paraffins, 10.7 % unsaturated aliphatics and the rest being other compounds.