Properties of Bio-Oil from Alga Fast Pyrolysis

Properties of bio-oil from alga fast pyrolysis were studied based on the molecular distillation. The composition of bio-oil and fractions was analyzed by GC-MS, and the thermal behavior of evaporation and decomposition was investigated using TG-FTIR. Fast pyrolysis of alga obtained a bio-oil yield of 20.54 % and a char yield of 31.12 % due to its low cellulose and hemicellulose content, and high lignin and extractives content. Light fraction accounted for about 85 % of the total bio-oil. It was mainly composed of volatile compounds, so its weight loss was completed before 200°C and evaporation was dominant during pyrolysis. But for heavy fraction, the weight loss was in the temperature range of 25-650°C due to the decomposition of phenols or sugars. Compared with bio-oil, light fraction had a worse thermal stability, and heavy fraction is better.