Using design of experiments to optimize derivatization with methyl chloroformate for quantitative analysis of the aqueous phase from hydrothermal liquefaction of biomass

René Bjerregaard Madsen, Mads Mørk Jensen, Anders Mørup, Kasper Houlberg, Per Sigaard Christensen, Maika Klemmer, Jacob Becker, Bo Brummerstedt Iversen, Marianne Glasius*

*Corresponding author for this work

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

38 Citations (Scopus)

Abstract

Hydrothermal liquefaction is a promising technique for the production of bio-oil. The process produces an oil phase, a gas phase, a solid residue, and an aqueous phase. Gas chromatography coupled with mass spectrometry is used to analyze the complex aqueous phase. Especially small organic acids and nitrogen-containing compounds are of interest. The efficient derivatization reagent methyl chloroformate was used to make analysis of the complex aqueous phase from hydrothermal liquefaction of dried distillers grains with solubles possible. A circumscribed central composite design was used to optimize the responses of both derivatized and nonderivatized analytes, which included small organic acids, pyrazines, phenol, and cyclic ketones. Response surface methodology was used to visualize significant factors and identify optimized derivatization conditions (volumes of methyl chloroformate, NaOH solution, methanol, and pyridine). Twenty-nine analytes of small organic acids, pyrazines, phenol, and cyclic ketones were quantified. An additional three analytes were pseudoquantified with use of standards with similar mass spectra. Calibration curves with high correlation coefficients were obtained, in most cases R 2 > 0.991. Method validation was evaluated with repeatability, and spike recoveries of all 29 analytes were obtained. The 32 analytes were quantified in samples from the commissioning of a continuous flow reactor and in samples from recirculation experiments involving the aqueous phase. The results indicated when the steady-state condition of the flow reactor was obtained and the effects of recirculation. The validated method will be especially useful for investigations of the effect of small organic acids on the hydrothermal liquefaction process.

Original languageEnglish
JournalAnalytical and Bioanalytical Chemistry
Volume408
Issue8
Pages (from-to)2171-2183
Number of pages13
ISSN1618-2642
DOIs
Publication statusPublished - 1 Mar 2016

Keywords

  • Hydrothermal liquefaction aqueous phase
  • Aqueous phase recirculation
  • Methyl chloroformate derivatization
  • Design of experiments
  • DRIED DISTILLERS GRAINS
  • GAS-CHROMATOGRAPHY
  • TECHNOECONOMIC ANALYSIS
  • CHLORELLA-PYRENOIDOSA
  • SUPERCRITICAL WATER
  • MICROALGAE
  • TECHNOLOGIES
  • SPECTROMETRY
  • FRACTIONS
  • SOLUBLES

Fingerprint

Dive into the research topics of 'Using design of experiments to optimize derivatization with methyl chloroformate for quantitative analysis of the aqueous phase from hydrothermal liquefaction of biomass'. Together they form a unique fingerprint.

Cite this