PEFTEC - Abstract

Abstract Information :

Plastic pyrolysis oil is of particular interest for the waste management in the current context of circular economy. Due to their uncontrolled origin, these oils may contain significant amount of unwanted compounds such as nitrogen-containing species. These compounds are known to be catalyst poisons during refining processes. Therefore, the removal of these species is crucial, and for this purpose, their characterization from a structural and quantification point of view is essential. This study presents a method to specify and quantify nitrogen-containing classes in a plastic pyrolysis oil by direct infusion mass spectrometry. Two steps were used, structural characterization in order to select suitable standards followed by semi-quantification. Structural speciation of nitrogen-containing compounds was first obtained by electrospray ionization Fourier transform mass spectrometry followed by tandem mass spectrometry using high-resolution mass isolation and infrared multiphoton dissociation fragmentation. A semi-quantification is then performed by standard addition method, very appropriate for such complex matrices. Aromatic cores such as quinoline and quinoxaline were evidenced for both N1 and N2 classes allowing to propose 2-methylquinoxaline and 2-butylquinoline as standards for the semi-quantification of N2 and N1-containing compounds respectively. The amount of nitrogen detected from the sum of individual species was consistent with the bulk analysis. The reported methodology can be applied to numerous other families of compounds in various other complex matrices.