Removal of H2S and Mercaptan from Outlet Gases of Kermanshah Refinery Using Modified Adsorbents (Bentonite and Sludge)

In this work, adsorbents, namely bentonite and sludge, modified by iron and copper were used to remove the H2S and mercaptan from Kermanshah refinery. The used adsorbents are inexpensive materials, which substantially decrease the operational costs. The structure of the adsorbents was analyzed using scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX). The effects of gas and flow rate on the H2S and mercaptan removal were also studied. The results indicated that the bentonite modified by iron has a high capacity for removing H2S (32.256 mg/g) and mercaptan (0.98 mg/g). Moreover, the adsorption capacity of the sludge modified by copper for removing H2S and mercaptan was 11.18 and 0.81 mg/g respectively. Furthermore, by increasing the flow rate and concentration of H2S and mercaptan, H2S and mercaptan concentrations in the sludge output gas increased, but no considerable change was observed in the bentonite output gas.