Abstract:
This research studied the adsorptive capacity and selectivity of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) in simulated diesel fuels containing polyaromatic or nitrogen compounds on activated carbon and alumina, modified with CU+ and Ni2+using different preparation methods. Direct impregnation by using CuCl/CH₃CN was found to be unsuitable due to the stability and low solubility of Cu+. Impregnation was therefore performed with and aqueous solution of CuCl₂ following by a reduction step of CuCl₂ into CuCl using H₂. For Ni2+, an aqueous solution of NiCl₂ was used. A suitable feed flow rate and granulometry of the adsorbent was found to be 0.4 cm³/min and 100 to 400 μm, while the optimum temperature was 60℃ and 90℃ for Ni²+and Cu+ impregnated alumina, respectively. The adsorption capacity at the sulfur breakthrough followed the order non-impregnated macroporous alumina < Cu+/macroporous alumina < non-impregnated mesoporous alumina < Cu+/mesoporous alumina < Ni²+/macroporous alumina < Ni²+/mesoporous alumina < Cu+/AC < non-impregnated AC. The breakthrough capacity of DBT was higher than 4,6-DMDBT for both of Ni²+and Cu+/mesoporous alumina Moreover, the breakthrough capacity of DBT without polyaromatic and nitrogen compounds was higher than that with polyaromatic and nitrogen compounds.
