Centrifugal partition chromatography as a fractionation tool for the analysis of lignocellulosic biomass products by liquid chromatography coupled to mass spectrometry

The conversion of lignocellulosic biomass into biofuels and bio-products leads to oxygenated matrices having a wide range of polarities and molecular weights. A complete analytical characterization of these complex mixtures is necessary to improve conversion processes. In this study, an innovative centrifugal partition chromatography (CPC) protocol was developed to fractionate aqueous biomass samples with a MTBE-water solvent system, by mixing elution, displacement and extrusion modes in the same run. This new protocol was validated on model molecules and applied to the water soluble phase of a fast pyrolysis bio-oil. It demonstrated a promising separation with a relevant selectivity on the most significant chemical families of biomass samples: carbohydrates, furans, carboxylic acids and phenols. CPC fractions of the sample were collected and analyzed comprehensively by HPLC-UV/MS (with ESI negative and positive ionization modes). This CPC x LC approach allowed more accurate attributions on the 217 peaks detected. The use of different detection modes gave a complete view of the water soluble phase of a fast pyrolysis bio-oil through 2D maps. Molecular characterization was enhanced by independent information: CPC retention time, LC retention time, UV and MS spectra. Concomitance of these different chemical information is of precious help for unambiguous identification. (C) 2019 Elsevier B.V. All rights reserved.