This communication evaluates the suitability of gas and liquid chromatography for the quantification of levoglucosan and hydroxyacetaldehyde in bio-oils. It was found that both techniques can principally determine levoglucosan quantitatively in cellulose/biomass derived bio-oils. However, it is also shown that oligo-anhydrosugars present in the bio-oils undergo depolymerisation to levoglucosan during gas chromatography, resulting in an overestimation of the concentration of levoglucosan. Hydroxyacetaldehyde can only be determined quantitatively by liquid chromatography. Presented experimental evidence shows that the high temperature (200–320 °C) of injection in gas chromatography is a key factor causing oligo-anhydrosugars and hydroxyacetaldehyde to react during analysis, which may lead to flawed results.
- Gas chromatography (GC)
- Liquid chromatography (LC)