Adsorption and Diffusion of Benzene and Thiophene Over Y/MCM-41 Composite Zeolite
Adsorption and Diffusion of Benzene and Thiophene Over Y/MCM-41 Composite Zeolite
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Y/MCM-41复合沸石对苯和噻吩的吸附与扩散
DOI：
10.1166/sam.2013.1564
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发表时间：
2013-08
影响因子：
0.9
通讯作者：
Qiang Wang
中科院分区：
文献类型：
--
作者：
Panpan Sui;Xiuhong Meng;Yuye Wu;Yuanyuan Zhao;Lijuan Song;Zhaolin Sun;Linhai Duan;Ahmad Umar;Qiang Wang
采用离子交换法合成了Y/MCM-41复合分子筛，并采用X射线衍射（XRD）、扫描电镜（SEM）、透射电镜（TEM）和红外光谱（IR）等手段对复合分子筛进行了表征，研究了苯和噻吩在NaY、Si-MCM-41、NaY/Si-MCM-41混合物上的吸附和扩散行为，和Y/MCM-41复合分子筛的吸附等温线和相对扩散系数。结果表明，苯和噻吩在该树脂上的吸附机理不同。苯的吸附主要是物理吸附，噻吩的吸附主要是电子吸附。苯和噻吩的吸附等温线在压力30 mbar附近出现拐点。在30 mbar以下，微孔中发生了孔隙填充，而在30 mbar以上，中孔中的吸附主要是毛细凝聚。吸附剂的酸量和酸强度对噻吩的吸附量影响较大，而对苯的吸附量影响不大。苯和噻吩在NaY、Si-MCM-41、NaY/Si-MCM-41混合物和Y/MCM-41的微孔通道中优先吸附。噻吩在NaY、Si-MCM-41、NaY/Si-MCM-41混合物和Y/MCM-41上的扩散系数大于苯。不同吸附剂的静态脱硫性能顺序为：Y/MCM-41 > NaY > YM（0.8）> YM（0.2）> YM（0.4）> YM（0.6）> Si-MCM-41。
Y/MCM-41 composite molecular sieve was successfully synthesized using ion exchange method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and infrared (IR) etc. Adsorption and diffusion behaviors of benzene and thiophene on NaY, Si-MCM41, NaY/Si-MCM-41 mixtures, and Y/MCM-41 composite molecular sieve were systematically studied to obtain adsorption isotherm and relative diffusion coefficient. It was found that the adsorption mechanisms of benzene and thiophene were different. The adsorption of benzene was mainly by physical adsorption, while electrons played a most important role in the adsorption of thiophene. An inflection appears around the pressure of 30 mbar in all adsorption isotherms of benzene and thiophene. The pore filling occurs in the microporous below 30 mbar, but above 30 mbar the adsorption is mainly the capillary condensing in mesoporous pore. The acid amount and acid strength of adsorbent had a great influence on the adsorption capacity of thiophene, but had little effect on benzene. Both benzene and thiophene were preferred to be adsorbed in micro-porous channels of NaY, Si-MCM-41, NaY/Si-MCM-41 mixtures, and Y/MCM-41. The diffusion coefficient of thiophene on NaY, Si-MCM-41, NaY/Si-MCM-41 mixtures, and Y/MCM-41 is larger than that of benzene. Static desulfurization performance of different adsorbents followed the order below: Y/MCM-41 > NaY > YM (0.8) > YM (0.2) > YM (0.4) > YM (0.6) > Si-MCM-41.