Adsorptive denitrogenation of light gas oil by silica-zirconia cogel

The characteristics of adsorption and desorption of nitrogen-containing compounds (NCCs) on the Si-Zr cogel were studied with regard to denitrogenation of light gas oil (LGO) through batch and dynamic experiments. The Si-Zr cogel adsorbent showed a high selectivity of NCCs due to the role of the zirconia on the cogel, regardless of the amount and types of sulfur-containing compounds (SCCs) in the LGO. When the temperature increased from 283 to 323 K, the adsorbed amount of NCCs increased and the time taken to reach the adsorption equilibrium grew shorter. On the other hand, the adsorbent regeneration by the solvent grew worse at higher temperatures when the desorption temperature was applied to the adsorbent used at the corresponding adsorption temperature. At 283 and 303 K, the methyl isobutyl ketone (MIBK) with higher polarity showed a better desorption of NCCs, while the degree of regeneration by methyl tertiary butyl ether (MTBE) at 323 K was the best. The adsorption of NCCs on the cogel was significantly affected by the presence of water in the LGO. While MTBE and MIBK effectively desorbed the adsorbed water with NCCs from the cogel, methyl phenyl ether (Anisole) with aromatic ring was not effective in treating the water. Since the adsorbent could select only the NCCs with high capacity from the LGO at mild temperature and ambient pressure, success in the adsorption technology process would lead to major advances in petroleum refining by facilitating the improvement of HDS as well as fuel cell applications by offering greater protection of the nitrogen-selective adsorbent. (D 2005 American Institute of Chemical Engineers AIChE J, 52: 510-521, 2006