Hydro-liquefaction of Lemna minor (Duckweed) with hydrogen-donor solvent at varying hydrogen pressures

ABSTRACT

The authors have investigated hydro-liquefaction of Lemna minor (duckweed) aquatic biomass and a hydrogen-donor solvent, methanol, at temperatures of 180 °C, 200 °C and 220 °C and final reactor pressure values of 70, 80 and 90 bar. The rise in reactor pressure for all reaction temperatures led to an increase in biocrude yield with a maximum higher heating value of 22.19 MJ/kg, while the biochar also depicted its potential to be used in varied applications and as a bio-refinery feedstock. Fourier Transform Infrared Spectroscopy and Gas Chromatography Mass Spectrometry analysis of biocrude indicated the presence of esters and long chain alkanes, ethers, phenols, etc. The main finding of this work disclosed that fuel properties of the present biocrude (without any catalyst) were better than their non-catalytic and hydro-catalytic bio-oil counterparts obtained from similar biomass at a pyrolysis temperature of 550 °C.

KEYWORDS:

• Lemna minor
• methanol
• hydro-liquefaction
• biocrude
• hydrogen pressure
• fuel and physical properties

Acknowledgements

The authors express their gratefulness towards the Analytical Lab, Department of Chemical Engineering, IIT Guwahati for making available the required analytical instruments for this study. They acknowledge the XRD facility availed from Central Instruments Facility, IIT Guwahati. They are also thankful to Biotech Park, Guwahati for the study of the biomass sample by CHNSO elemental analyzer and biocrude by Gas Chromatography Mass Spectrometry (GC-MS) facility.

Disclosure statement

No potential conflict of interest was reported by the author(s).