Effect of Temperature on the Molecular Weight Distribution in the Different Ranks of Coal during the On-Line Investigation of Coal Pyrolysis Gas Using Direct Photoionization Mass Spectroscopy

Makhosazana Mthembu^1,2*, Ralf Zimmermann^1,3, Thorsten Streibel^1,3, Martin Sklorz¹

¹Joint Mass Spectrometry Centre, Chair of Analytical Chemistry, Institute of Chemistry, University of Rostock, Rostock, Germany.
²Sasol Group Technology R&T, Sasolburg, South Africa.
³Joint Mass Spectrometry Centre, Department of Comprehensive Molecular Analytics (CMA), Helmholtz Zentrum München, Oberschleissheim, Germany.

DOI: 10.4236/ijcce.2015.44007                

Abstract

Coal pyrolysis gas from different ranks of coal was monitored on real time basis using photoionization mass spectroscopy. The molecular weight distribution of different products as a function of temperature from various coal ranks studied was observed. It was noted that the release of different classes of compounds like phenols, alkenes, alkylated aromatics and aromatic skeletons was temperature dependent. For all the coal ranks at lower temperatures phenols were the main component, with alkenes and alkylated aromatics at slight higher temperatures and aromatic skeletons were released at the highest temperatures studied.

Keywords

Coal Ranks, Photoionization, Temperature Effect, Molecular Weight Distribution, Coal Pyrolysis Gas

Conflicts of Interest

The authors declare no conflicts of interest.

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