Pyrolysis of lipids for the production of renewable fuels and chemicals

The primary objective of this work was to study the pyrolytic conversion of lipids to produce deoxygenated, liquid hydrocarbon products for use as renewable chemicals or fuels. The focus of this fundamental work included identification of primary lipid pyrolysis products at different reaction conditions. Stearic acid was used as a model compound and reacted at different conditions in 15 ml batch reactors. Results show the formation of a distinct n-alkane/alkene series formed by decarboxylation of stearic acid and subsequent thermal cracking. Reaction temperatures from 410-430°C and times ranging from 1-8 hours appear to be the optimal conditions for obtaining a liquid product of n-alkanes/alkenes with minimal gas, solid and aromatic formation. Neat oils and fats were first hydrolyzed to convert triglycerides into free fatty acids and then pyrolyzed. Results show the presence of the n-alkane/alkene series as well as numerous branched hydrocarbon products.