Abstract:High standard emission regulations require that vehicle exhaust gas purification catalyst adsorbs and stores hydrocarbons (HC) during vehicle cold start stage, and then desorbs and purifies them at normal operating temperature. Toluene is main component of HC in tail gas of gasoline vehicles. Therefore, NaY, USY and ZSM-5 molecular sieves were selected to prepare different molecular sieve materials modified by CeO2. Adsorption and desorption properties of toluene were characterized and analyzed by N2 physical adsorption instrument, high resolution transmission electron microscope (TEM), chemical adsorption instrument and X-ray diffraction (XRD) instrument. The results show that adsorption capacity of USY zeolite to toluene is the best before modification, saturated adsorption capacity of toluene is 245.9 mg/g, and toluene desorption temperature range is 290—360 ℃. Adsorption capacity of molecular sieve is significantly improved after CeO2 modification, among which CeO2/USY material has a best adsorption capacity for toluene, reaching to 270 mg/g, which is about 10% higher than that of unmodified USY.