Study of Isothermal Equilibrium,Kinetics and Thermodynamics of Adsorptive Desulfurization on Synthesized Cu~ⅠY~ⅢY Zeolite

Deep adsorptive desulfurization of low sulfur content gasoline via zeolite is a promising process.Herein,the Cu~ⅠY~ⅢY zeolite was prepared and the effect of adsorption conditions and aromatics on the performance of adsorptive desulfurization was studied.And the isothermal equilibrium and kinetics were also investigated.The results showed that upon using 10 m L of model oil and 0.2 g of the Cu~ⅠY~ⅢY adsorbent during the adsorption reaction,which was carried out at 323 K for 60 min,the benzothiophene(BT) desulfurization rate reached 98.4%.The impact of aromatics on the adsorptive desulfurization over the Cu~ⅠY~ⅢY zeolite decreased in the following order:ortho-xylene meta-xylene para-xylene.The equilibrium isotherm shows that the adsorption of benzothiophene over the as-prepared CuIYIIIY zeolite can be represented by the Langmuir model.And the kinetics can be more perfectly represented by the pseudo-second-order model than that of the pseudo-first-order one.The thermodynamic parameters(ΔG,ΔH) were both negative,which suggested that the adsorption process is monostratal,mass transfer controlled,spontaneous,and exothermic.