Effect of nitrogen compounds on adsorptive desulfurization of a model fuel with Zn(II) Y and Zn(II) X zeolites

Nitrogen compounds (i.e., acridine and carbazole) were found to have strong inhibiting effects on desulfurization by Zn( II ) Y and Zn( II ) X zeolites. The effects of each individual molecule were studied by using a model liquid feed stream (300 ppmw thiophene in 80% n-octane and 20% benzene) in a fixed-bed adsorption system and the results compared on the basis of the breakthrough curves. The desulfurization performancefor Zn( II ) Y was lower than Zn( II ) X at the same concentration of components and the adsorption of adsorbate over the same zeolite decrease as a following: acridine > carbazole > thiophene. Therefore, the presence of nitrogen compounds has a strong effect on deep desulfurization.