AgY分子筛对燃料油中噻吩及苯并噻吩的吸附性能

Adsorptive Performance of Synthesized AgY Zeolite for Thiophene and Benzothiophene in Fuel

采用固相离子交换法制备了AgY分子筛,通过静态吸附实验,研究了AgY分子筛对模拟燃料油中有机硫化物噻吩(T)和苯并噻吩(BT)的吸附平衡和吸附动力学特性,并用Freundlich、Langmuir、Toth吸附模型以及准n阶和修正的准n阶动力学方程分别对吸附平衡数据和吸附动力学数据进行拟合,同时分析AgY分子筛吸附T和BT过程中的质量传递和颗粒内扩散。结果表明,Langmuir、Toth吸附模型和修正的准n阶动力学方程能够很好地描述AgY分子筛对燃料油中T及BT的吸附行为,且AgY对BT的吸附能力强于对T的吸附;T和BT从溶液中传递到吸附剂外表面是一个非常快速的过程,随着颗粒内部扩散的进行,扩散速率逐渐减慢直至平衡,颗粒内部扩散对BT的影响较大。

AgY zeolite was prepared via solid state ion exchanged method under the condition of N2 at high temperature.Adsorptive desulfurization of model fuel was conducted in a batch reactor to evaluate the equilibrium and kinetics of the organic sulfur compounds thiophene（T）and benzothiophene（BT）adsorption onto AgY zeolite.Adsorption equilibrium data were fitted with Freundlich,Langmuir and Toth adsorption models,and pseudo-n-order equation and modified pseudo-n-order equation was used to fit the kinetic of the adsorption process.The mass transfer analysis and intra-particle diffusion analysis during the adsorption of T and BT on AgY were carried out.The results showed that the equilibrium adsorption data were fitted to Langmuire and Toth models and the BT interacted with zeolite more strongly than T.The corresponding parameters and correlation coefficients of each model were obtained,which could be used to predict the T and BT adsorption on AgY zeolite.The transfer process of T and BT from fuel oil onto the adsorbent was rapid enough,and T and BT diffused quickly in the initial adsorption stage,and then intra-particle diffusion slowed down and stabilized.The influence of intra-particle diffusion on BT was stronger than that on T.