ACIDIC OXYGEN COMPOUNDS IN THE IRATI SHALE OIL

This work reports the principal alkylphenols (4 wt %) and carboxylic acids (1.2 wt %) present in the Irati Shale oil (Sao Mateus do Sul, Parana) by means of a combination of gas chromatography-mass spectrometry (GC-MS) and retention time data of standard compounds. It appears that the phenols are essentially monocyclic in nature with methyl groups as the main substituents. Carboxylic acids are principally linear and predominantly of the range C-14-C20. After catalytic hydrotreatment (400-degrees-C, 125 atm) high hydrodeoxygenation levels were obtained (87 wt %) for phenols and carboxylic acids, although the relative distribution of the various compounds was not significantly changed. Oxygen is present in the carbonaceous residue as several functionalities (xanthenes, phenols, aryl ethers, carbonyl compounds, and furanic structures). The remaining acidic compounds may cause instability of the treated shale oil.