Hydrothermal liquefaction of Nannochloropsis oceanica in different solvents

M.P. Caporgno (1) , Jeremy Pruvost (2) , J. Legrand (2) , O. Lepine (3) , Mohand Tazerout (4, 5) , C. Bengoa (1)

1 Departament d′Enginyeria Quimica
2 GEPEA-BAM - Bioprocédés Appliqués aux Microalgues
3 Algosource Technologies
4 GEPEA-VERTE - Valorisation Energie-matière des Résidus et Traitement des Emissions
5 Mines Nantes - Mines Nantes

Although the hydrothermal liquefaction is considered a promising technology for converting microalgae into liquid biofuels, there are still some disadvantages. This paper demonstrated that the bio-oil yield can be significantly improved by adding alcohols as co-solvents and carrying out the conversion at mild conditions (<250 °C), but at the expense of a reduced bio-oil quality. By adding ethanol, the bio-oil yields obtained (up to ∼60%) were comparable to the yield obtained at severe operating conditions using only water as solvent (54 ± 2% on average), but the quality of the bio-oil was lower. However, the main advantages of the process here described lie in the utilisation of wet microalgae (∼75% moisture) and alcohol concentrations which avoid both drying the microalgae and decreasing the amount of microalgae loaded in the reactor.

Mots clés: Bio-oil; Co-solvents; Hydrothermal liquefaction; Microalgae

Domaines: Génie chimique; Génie des procédés

M.P. Caporgno, Jeremy Pruvost, J. Legrand, O. Lepine, Mohand Tazerout, et al.. Hydrothermal liquefaction of Nannochloropsis oceanica in different solvents. Bioresource Technology, 2016, 214, pp.404-410. ⟨10.1016/j.biortech.2016.04.123⟩. ⟨hal-01949513⟩