Adsorptive removal of sulfur compounds from transportation fuels by using zeolitic adsorbents

Abstract

This research work was conducted to study the modification of NaY zeolite by ion-exchanging with selected transition metal ions (Cu2+, Ni2+) in order to enhance the capacities of adsorbents for adsorptive removal of refractory sulfur compounds which are difficult to remove by using conventional methods. The efficiencies of the Cu(II)Y and NiY zeolites in removing model sulfur compounds (3-methylthiophene, benzothiophene and dibenzothipohene) from simulated transportation fuels as isooctane and decane were examined and systematically related to type and amount of metal loading by batch method at ambient conditions. The amount of metal loading on both CuY and NiY zeolites was varied by using different amount of metal solution to NaY zeolite ratio. The results showed that the adsorption isotherms were well fitted with Langmuir isotherm. From the results, CuY zeolite showed markedly high adsorptive capacities in adsorbing 3-MT, BT and DBT than NiY and NaYzeolites. The adsorption capacity of CuY zeolite was directly proportional to the amount of Cu2+ loading instead of NiY zeolite which had low Ni2+ dependency. The difference in adsorption capacities was probable due to the effect of pore size of zeolite after exchanged with transition metals.