PEFTEC - Abstract

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Abstract Type: Seminar
Session Choice: Comprehensive technology 2D GC, 2D LC applications
Presenter Name: Mr Eric Brander
Co-authors:Dr Anupam Giri
Mr Gerard Kwakkkenbos
Mr Geoff Chappell
Company/Organisation: SABIC
Country: Netherlands

Abstract Information :

Analysis of heavy constituents of petrochemical products or by-products remains a challenging task due to both low volatility, making them inaccessible for gas chromatography, as well as low solubility in common solvents, making them inaccessible for liquid chromatography. Moreover, analysis of semi-solid or solid residues from petroleum refineries, such as vacuum residues, fouling deposits from steam cracker facilities or polymeric residues, requires a completely different approach to sample introduction. There is always a thrust to elevate the elution of heavier compounds for chromatographic separation. In addition, finding an effective approach to characterize non-elutable organic heavies also remained important.rnIn this study, first, an attempt has been made to elute native heavy species in such samples, by optimizing several aspects of the GC process, including column length, flow, injector and oven temperatures etc. Second, pyrolyzer injector coupled to GCGC-HRMS was deployed to introduce intact molecules at lower temperature, as well as thermally degraded pyrolysis products at pyrolysis temperature, from semi-solid or solid residues. Thirdly, the thermal decomposition pathways of several polymers were investigated for better understanding of their degradation mechanisms. rnApplying pyrolysis GCGC coupled to EI-MS allowed separation of hydrocarbon classes resulting from polymer decomposition, along with heteroatom-containing species, in a grouped, structured manner. However, due to the high complexity of evolving constituents and extensive fragmentation occurring with EI, the identification of most of the pyrolysis products remained inconclusive. To minimize fragmentation, pyrolysis GCGC was coupled to photo-ionization PI high-resolution mass spectrometry. Low energy PI yielded enhanced sensitivity and selectivity as a result of the dramatic reduction in fragmentation, as well providing an increase in the number of compounds identified. Applying of high-resolution MS combined with soft photo-ionization was found to be extremely useful and will be discussed.