Adsorption of the organic sulfur compounds thiophene (TP) and I -benzothiophene (I -BTP) in an organic model solution of hydrodesulfurizated gasoline (heptane with 1 wt% toluene and 0. 156 mM (5 ppmw as sulfur) TP or I-BTP) was Studied by a batch method at 80 C using metal-ion-exchanged Y-zeolites. Although NaY-zeolite or its acid-treated material rarely adsorbed the organic sulfur compounds, NaY-zeolites exchanged with Aa<SUP>+. CL2+. and Ce3+ ions and NH</SUP><INF>4</INF><SUP>Y-zeolites exchanged with Ce3+ ions showed markedly high adsorptive capacities for TP and I -BTP. The Sulfur uptake increased in the order CuY-zeolite(Na) < AgY-zeolite(Na) < CeY-zeolite(Na) for both the organic Sulfur compounds. The adsorption isotherms for TP and I -BTP followed the Langmuirs relationship and the saturation capacities by CeY-zeolite(Na) were calculated as 0.022 and 0.033 mmol/g, respectively. The mole ratios of TP/Ce and I-BTP/Ce were 0.03 1 and 0.047, respectively. CeY-zeolite(NH</SUP><INF>4</INF><SUP>) which was prepared from NH</SUP><INF>4</INF>Y-zeolite showed less uptake of TP and I -BTP than CeY-zeolite(Na). probably due to its lower cerium content. 2004 Elsevier Inc. All rights reserved.