(526b) Enhancing the Capacity of Silver Based Adsorbents for Desulfurization of Liquid Hydrocarbon Fuels

Adsorptive desulfurization provides a viable alternative to producing low sulfur fuels from conventional sources such as diesel, gasoline and jet fuel. Such feeds are a prerequisite for the operation of most reformer catalysts as well as fuel cells. Supported silver adsorbents have demonstrated high capacity for sulfur in liquid fuels. For JP5 with a total sulfur concentration of 1172ppmw, this adsorbent demonstrated a 8-10mg/g sulfur capacity. The atomic silver utilization at 2% weight loading for desulfurization was found to be 95% using JP5. Lower atomic utilization was observed at higher silver weight loadings. Thus the sulfur capacity can be significantly improved by increasing the silver utilization at higher loadings. The lowering of silver utilization is attributed to the increase in crystallite size of silver on the support. This study examined the effect of preparative conditions on the dispersion of silver on the TiO2 support. The factors considered were the support pre-treatment, conditions during impregnation, drying and calcination steps. The desulfurization performance was correlated to adsorbent surface morphology using oxygen chemisorption, XPS and TEM data.