Hydrothermal liquefaction of isolated cuticle of Agave americana and Capsicum annuum: Chemical characterization of petroleum-like products

• Hydrothermal liquefaction of cuticular materials led to a 38–41 wt.% bio-oil yield.
• Bio-oils HHVs were ∼40.5 MJ kg−1 and contained low amounts of heteroatoms.
• Comprehensive chemical analysis of feedstock cuticular materials and bio-oils.
• 2D GC–MS and ESI-FTICR-MS were utilized to chemically characterize the bio-oils.
• Bio-oils produced contained desirable fuel related compounds.

Hydrothermal liquefaction (HTL) of cuticular materials from Agave americana and Capsicum annuum was performed for extended periods of time (72 h) at 360 °C meant to simulate long-term maturation of the organic matter. Both cuticular materials displayed evidence for possible oil production from the amounts of polymethylenic carbons in 13C solid-state nuclear magnetic resonance spectra. The bio-oil yields were approximately 35 wt.% and exhibited heating values of 40.5 MJ kg−1, comparable to those of typical crude petroleum. Analysis by two dimensional gas chromatography indicated that the A. americana bio-oil was dominated by a homologous series of n-alkanes, whereas cyclic and aromatic compounds were the major compounds identified in the C. annumm bio-oil. Further analysis using electrospray ionization-Fourier transform ion cyclotron resonance-mass spectrometry revealed the bio-oil samples were predominantly lipid-like in character. The result of this study demonstrate that one can utilize highly aliphatic biopolymeric components of certain plant materials to produce bio-oils that have the potential to be utilized as alternative fuels.