Lipids extraction of Nannochloropsis and hydrothermal liquefaction of defatted Nannochloropsis

To improve the comprehensive utilization efficiency of microalgae, dry or wet Nannochloropsis were extracted with different solvent and hydrothermal liquefaction (HTL) experiments of defatted Nannochloropsis were carried out to explore the effects of defatted methods on HTL products. The solvent extraction results showed that polar solvent can extract 25.0% of lipids from microalgae without selectivity, which resulted in only 29.68% for the fatty acid methyl ester yield of the extracts; the fatty acid methyl ester recovery of mix solvent was 57.70%. For the HTL bio-crude of defatted Nannochloropsis, the yield was 27.7%-34.6%, nitrogen content was 5.29%-6.68%, mainly consisted of fatty acid, fatty acid esters, fatty acid amides, long-chain hydrocarbon, amines, oxygen-containing compounds and nitrogen-containing heterocyclic compounds. The yield of wet algae hydrothermal crude oil after methanol extraction was 34.6%, the nitrogen content was 5.44%, and the process energy consumption was low, indicating that methanol extraction wet algae combined with hydrothermal liquefaction has certain application prospects. © All Right Reserved.