Influence of monovalent alkaline metal cations on binder-free nano-zeolite X inpara-xylene separation  

对二甲苯分离中单价碱金属离子对无粘合剂纳米沸石X的影响(英文)

作　　者：Milad Rasouli Nakisa Yaghobi Seyedeh Zahra Movassaghi Gilani Hossein Atashi Majid Rasouli 

机构地区：[1]Department of Chemical Engineering, Faculty of Engineering, University of Sistan and Baluchestan [2]Petrochemical Department, Iran Polymer and Petrochemical Institute [3]Chemical Engineering Department, Amirkabir University of Technology

出　　处：《Chinese Journal of Chemical Engineering》2015年第1期64-70,共7页中国化学工程学报（英文版）

摘　　要：The adsorption process was studied for separating para-xylene from xylene mixture on modified nano-zeolite X in a breakthrough system. Nano-zeolitic adsorbent with different ratios of Si O2/Al2O3 was synthesized through hydrothermal process and ion-exchanged with alkaline metal cations like lithium, sodium and potassium. The product was characterized by X-ray diffraction, scanning electron microscopy(SEM), nitrogen adsorption,transform electron microscopy(TEM) and in situ Fourier transform infrared(FTIR) spectroscopy. The influence of nano-zeolite water content and desorbent type on the selectivity of para-xylene toward other C8 aromatic isomers was studied. The optimization of adsorption process was also investigated under variable operation conditions. The isotherm for each isomer of C8 aromatics and the desorbents possess the adsorption characteristics of Langmuir type. The selectivity factor of para-xylene relative to each of meta-xylene, ortho-xylene and ethylbenzene under the optimum conditions obtained to be 5.36, 2.43 and 3.22, in the order given.The adsorption process was studied for separating para-xylene from xylene mixture on modified nano-zeolite X in a breakthrough system. Nano-zeolitic adsorbent with different ratios of Si O2/Al2O3 was synthesized through hydrothermal process and ion-exchanged with alkaline metal cations like lithium, sodium and potassium. The product was characterized by X-ray diffraction, scanning electron microscopy（SEM）, nitrogen adsorption,transform electron microscopy（TEM） and in situ Fourier transform infrared（FTIR） spectroscopy. The influence of nano-zeolite water content and desorbent type on the selectivity of para-xylene toward other C8 aromatic isomers was studied. The optimization of adsorption process was also investigated under variable operation conditions. The isotherm for each isomer of C8 aromatics and the desorbents possess the adsorption characteristics of Langmuir type. The selectivity factor of para-xylene relative to each of meta-xylene, ortho-xylene and ethylbenzene under the optimum conditions obtained to be 5.36, 2.43 and 3.22, in the order given.

关 键 词：Nano-zeolite X ADSORPTION C8aromatics ISOTHERM 

分 类 号：TQ241.13[化学工程—有机化工] TQ424.25