Hydrothermal liquefaction of Cyanophyta: Evaluation of potential bio-crude oil production and component analysis

This study investigated the effects of temperature (220-400 °C), reaction time (10-60 min), solid content (5-30%), and water density (0.11-0.58 g/ml) in hydrothermal liquefaction (HTL) of Cyanophyta for bio-crude. The maximum bio-crude yield of 39.54% was obtained at 370 °C, 10 wt.% solid concentration, and 50 min reaction time. Water density was not an important factor at the conditions studied. The biocrude contained phenols, benzene, alkanes, ketones, esters, aliphatic compounds and high content of N-containing heterocyclic compounds. High temperature (370 °C) favored formation of phenols, benzene, alkanes, fatty acids and PAHs, whereas relatively lower temperature condition (320 °C) favored producing alkenes and N-containing heterocyclic compounds.