Denitrogenation of raw diesel fuel by lithium-modified mesoporous silica

Lithium-modified mesoporous silica adsorbents (YSP-Li and MCF-Li) were prepared in order to selectively remove nitrogen compounds from residue hydrodesulfurization diesel (RHDS DSL: 271.3 ppmw of nitrogen compounds and 430.2 ppmw of sulfur compounds) provided by a refinery factory. Adsorption properties, such as the adsorption capacity, adsorption rate, and the regeneration ability toward nitrogen and sulfur compounds, were measured through batch experiments at 15 and 45 C. They were compared with the results of previously reported Si-Zr cogel experiments. The lithium-modified mesoporous silica adsorbents exhibited a much stronger adsorption affinity for nitrogen compounds than for sulfur compounds. With regards to the adsorption capacity and the adsorption rate, the lithium-modified mesoporous silica adsorbents exhibited improved performance when compared to Si-Zr cogel. Furthermore, the Li-modified adsorbents, especially YSP-Li, could be easily regenerated by MIBK, an organic solvent. (C) 2010 Elsevier B.V. All rights reserved.