Hydrodesulfurization and Hydrodearomatization of Kerosene over high metal loading Ni w/γ-Al2O3 Catalyst

Abstract

The present research investigates hydrodesulfurization (HDS) and hydrodearomatization (HAD) of raw kerosene with 0.364 wt. % sulfur and 16.498 wt. % aromatics supplied from Al-Dura Refinery. Hydrotreating reactions were carried out in one stage reactor over high metal  Ni W/γ-Al₂O₃ prepared catalyst at different temperatures 275-350^oC, pressures 32-62 bar, LHSV 1-4 hr^-1, and H₂/HC ratios 200-500. The prepared catalyst was pre-sulfided remarkably at low temperature and high pressure to avoid risky of sintering associated with gaining the active sulfide phase at high temperatures.  Results showed an obvious differences between HDS and HAD rates due to difficulty of polyaromatics saturation compared with desulfurization. Sulfur and aromatics removal were achieved from 74.9% to 95.6% and from 1% to 12.8% respectively at different operating conditions. Advanced saturation conditions were promoted the hydrogenation reaction bath and played a significant role for achieving acceptable levels of HDS and HDA.  In general, HDS and HDA increased with decreasing LHSV and increasing temperature, pressure, and H2/HC ratio. Burning quality, fire hazard, and aromatics content of kerosene were characterized by measuring of smoke point, flash point, and aniline point respectively. These properties were enhanced at different hydrotreating conditions due to the skeletal conformation change of kerosene hydrocarbons during reactions.