Advancing characterization of pyrolysis products: Comprehensive gas chromatography methods for analytes in gas and liquid phases

The development of biofuel technologies depends on the accurate identification and quantification of products from the conversion processes. Given the complexity of the renewable resources, the availability of biomass, and the versatility of conversion methods, there is a need for characterization methods that provide rapid and reliable analysis for various products coming from different conversion processes with minimal sample preparation. This study develops and validates gas chromatography methods that use multiple detectors to analyze pyrolytic compounds in both gas and liquid phases efficiently in a single, rapid run. For gas products, flame ionization and thermal conductivity detectors were used for identification and quantification of organic and inorganic gases, with volume and mass concentrations showing <1 % error between calculated and referenced values. A method for analyzing liquid product containing hydrocarbons and fatty acids was developed without derivatization, using a simultaneous mass spectrometer for identification and a flame ionization detector for quantification. Validation against established methods demonstrated comparable results, utilizing less time. While the simultaneous dual detector feature provides a simple and rapid analytical tool for pyrolysis products, these methods are also adaptable to non-simultaneous instrument setups and are broadly applicable to any general pyrolysis products containing hydrocarbons and oxygenates, making them useful for improving the development of biofuel production technologies.