Kinetics and thermodynamics of thiophene adsorption on CuCeY molecular sieve prepared by ultrasound-assisted ion exchange

CuCeY molecular sieves(CuCeY-U)were prepared through ultrasound-assisted ion exchange method and used in adsorption of thiophene from model gasoline. Adsorption capacity of the CuCeY-U was compared with the CuCeY molecular sieves(CuCeY-C)prepared by conventional ion exchange method. Thermodynamics and kinetics for the adsorption of thiophene on the CuCeY-U were studied through static experiments, and influence of temperature on the adsorption was investigated. The results showed that the influence of temperature on the adsorption was small. The adsorption of thiophene on the CuCeY-U accorded with Langmuir isotherm and was in agreement with pseudo-second-order rate equation. The adsorption rate was controlled not only by intra-particle diffusion but also by extra-particle diffusion. Thermodynamic parameters, namely ΔG, ΔH and ΔS, for the adsorption were calculated and ΔG < 0, ΔH > 0 and ΔS > 0 were obtained, which indicated that the adsorption of thiophene on the CuCeY-U was a spontaneous endothermal process.