Effect of Severity on Hydrotreating of Demetallized OH Monitored by ~1H-NMR Spectroscopy

摘要

A study on aromatic hydrogenation of demetallized oil has been carried out using a commercial catalyst under pilot plant reaction conditions similar to those found in industrial processes. The feedstock was contacted with the catalysts in a trickled bed reactor unit at 330 deg C, 350 deg C, and 370 deg C. A combination of physicochemical characterization of feed and products and ~1H-NMR spectra was used to monitor changes in the aromatic fractions caused by variation in reaction temperature. Analysis of the ~1H-NMR spectra, along with the quantitative variation in the areas of the resonance lines, showed that the diaromatics with relatively long alkyl changes present in the lightest distillation cuts of the products were highly hydrogenated. In contrast, smaller changes in aromaticity in the heaviest fractions were observed under the same conditions. A limit of about 2 wt% of the integrals corresponding to the diaromatic+ species suggests a thermodynamical limitation of hydrogenation under the studied reaction conditions.