Pd-Impregnated activated carbon and treatment acid to remove sulfur and nitrogen from diesel

Removal of sulfur and nitrogen compounds from national commercial diesel through adsorption onto activated carbon was studied. Brazilian commercial activated carbon samples (AC) were modified by acid oxidation and, alternatively, were impregnated with palladium chloride. Modified carbon samples showed a significant increase in the quantity of acid sites, particularly those AC submitted to impregnation with palladium. Adsorption capacity of the carbon samples increased proportionally to the increase in the acid groups. Adsorption efficiency of the activated carbon impregnated with palladium chloride was over 85% for nitrogen compounds and over 60% for sulfur compounds. The treatment studied was found to be an efficient option for the removal of sulfur and nitrogen compounds present in commercial diesel, and thus it could be an alternative pretreatment in the conventional hydrotreatment process.