合成了金属有机骨架MIL-53(Al)和MIL-53(Al)-NH2,并且将其作为吸附剂去除油品中的含氮化合物(喹啉和吡咯)。采用X射线衍射(XRD)、扫描电镜(SEM)、FT-IR光谱以及热重分析等对两种吸附剂进行了表征。结果表明,MIL-53(Al)-NH2能够快速地吸附油品中的喹啉/吡咯并且显示了较高的吸附容量,但MIL-53(Al)对喹啉/吡咯的吸附容量较低,原因是MIL-53(Al)-NH2和喹啉之间存在有利的氢键结合,但MIL-53(Al)-NH2与吡咯的氢键作用相对较低。研究了影响吸附容量的因素,包括吸附时间和温度。采用准一级和准二级动力学模型拟合了喹啉和吡咯的吸附数据,研究了MIL-53(Al)-NH2对喹啉和吡咯的吸附等温线和吸附热力学。通过简单的溶剂洗涤使得MIL-53(Al)-NH2再生,并重新用于吸附过程。%The metal-organic frameworks, MIL-53 ( Al)-NH2 and MIL-53 ( Al) , were synthesized and used as the adsorbents for the removal of nitrogen-containing compounds ( quinoline and pyrrole) from model fuel. The adsorbents were characterized by X-ray diffraction ( XRD ) , scanning electron microscopy ( SEM ) , FT-IR spectroscopy, and thermogravimetric analysis. Compared with the adsorption capacity of MIL-53 ( Al) , MIL-53 ( Al) -NH2 possesses a higher adsorption capacity for quinoline and pyrrole in the model fuel due to the hydrogen bonding interaction between MIL-53(Al)-NH2 and the nitrogen-containing compounds. The factors affecting the adsorption capacity are the adsorptive time and temperature. Furthermore, the pseudo-first-order and pseudo-second-order adsorption kinetics models were tested. It is found that the pseudo-second-order kinetics model is preferable to characterize the adsorption process. The adsorption isotherms and adsorption thermodynamics of quinoline and pyrrole on the MIL-53(Al)-NH2 were also evaluated. The calculation of separation factor RL and thermodynamic parameters (△G0 ,△H0 和△S0 ) show that the adsorption of quinoline / pyrrole on the MIL-53 ( Al)-NH2 is a spontaneous and exothermic process. The used MIL-53 ( Al)-NH2 could be regenerated by simple solvent washing with ethanol and reused in the adsorption process.
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