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A novel type of metal oxide/activated carbon catalyst was prepared by sol-gel method for the hydrolysis of carbonyl sulfide (COS).The influences of the calcination temperature,additive content (2.5%-10.0% Fe2O3,mass fraction) and the basicdensity of the activation process were thoroughly investigated.The surface of catalysts was characterized by Boehm titration.The products were characterized by scanning electron microscopy (SEM),X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS).The results show that catalysts with 2.5%-5.0% Fe2O3 after calcining at 500℃ have superior activity.The conversion rate of COS increases with increasing the relative density of basic capacity loaded onto activated carbon(AC),and the activity follows the order:KOH>Na2CO3>NaHCO3.Boehm titration data clearly show that the total acidity increases (from 0.06 to0.48 retool/g) and the basic groups decrease (from 0.78 to 0.56 mmol/g) after COS hydrolysis and H2S adsorption.The XPS results show that the product of H2S may be absorbed by the interaction with metal compounds and O2 to form sulfate (171.28 eV) and element sulfur (164.44 eV),which lead to catalysts poisoning.