Pyrolysis and catalytic pyrolysis of protein- and lipid-rich feedstock

In this study, pyrolysis of microalgal remnants was investigated for recovery of energy and nutrients. Chlorella vulgaris (C.vulgaris) biomass was first solvent-extracted for lipid recovery then the remnants were used as the feedstock for fast pyrolysis experiments using a fluidized bed reactor at 500 o C. Yields of bio-oil, biochar and gas were 53, 31, and 10wt.%, respectively. Bio-oil from C.vulgaris remnants was a complex mixture of aromatics and straight-chain hydrocarbons, amides, amines, carboxylic acids, phenols and other compounds with molecular weights ranging from 70Da to 1200Da. Structure and surface topography of the biochar were analyzed.The high inorganic content (potassium, phosphorous, and nitrogen) of the biochar suggests it may be suitable to provide nutrients for crop production. The bio-oil and biochar represented 57 and 36% of the energy content of the microalgae remnant feedstock, respectively.