Effect of Pretreatment on PAH Contents in Extracts from Xinwen Coal

Abstract

Xinwen coal was pretreated with different processes, namely, swelled by (a) alcohol/water or by (b) benzene/alcohol mixed solvent, (c) oxidized with 30% H₂O₂, and (d) reduced the oxidized sample with NH₂OH·HCl. The raw and pretreated samples were extracted with petroleum ether as the first step and then extracted with benzene as the second step, respectively. The extracts were analyzed by gas chromatograph-mass spectrometer, and four polycyclic aromatic hydrocarbons in the extracts are quantified. The results showed that all of the extracts' yields and the contents of these four polycyclic aromatic hydrocarbons in extracts were different according to the pretreatments and the extracting solvents.

Keywords::

• coal
• extract
• polycyclic aromatic hydrocarbons
• oxidation
• reduction
• swell