物理化学学报 >> 2015, Vol. 31 >> Issue (11): 2158-2164.doi: 10.3866/PKU.WHXB201510091

催化和表面科学 上一篇    下一篇

CeO2对CuCl/活性炭吸附剂C2H4/C2H6吸附分离性能促进作用

邢建东1,2,敬方梨1,2,储伟1,2,*(),孙红丽1,喻磊1,张欢1,罗仕忠1,*()   

  1. 1 四川大学化学工程学院,成都610065
    2 四川大学新能源与低碳技术研究院,成都610207
  • 收稿日期:2015-07-10 发布日期:2015-11-13
  • 通讯作者: 储伟,罗仕忠 E-mail:chuwei1965scu@163.com;luosz@scu.edu.cn
  • 基金资助:
    国家自然科学基金(21476145)

Improvement of Adsorptive Separation Performance for C2H4/C2H6 Mixture by CeO2 Promoted CuCl/Activated Carbon Adsorbents

Jian-Dong. XING1,2,Fang-Li. JING1,2,Wei. CHU1,2,*(),Hong-Li. SUN1,Lei. YU1,Huan. ZHANG1,Shi-Zhong. LUO1,*()   

  1. 1 School of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
    2 Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu 610207, P. R. China
  • Received:2015-07-10 Published:2015-11-13
  • Contact: Wei. CHU,Shi-Zhong. LUO E-mail:chuwei1965scu@163.com;luosz@scu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21476145)

摘要:

通过等体积浸渍方法制备了添加CeO2助剂的用于C2H4/C2H6吸附分离的CuCl/活性炭(AC)吸附剂,使用氮气吸附-脱附曲线、X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、能量分散X射线光谱(EDX)等分析方法对吸附剂进行了表征.结果表明,吸附剂表面Cu(II)在氮气气氛焙烧过程中被部分还原成Cu(I).重点研究了Ce元素的添加对于吸附剂的C2H4/C2H6吸附分离性能的影响,等温吸附曲线结果表明添加了CeO2的吸附剂通过降低乙烷的吸附容量从而显著提高了吸附分离性能. XRD及XPS结果表明,和未添加助剂样品相比,其表面晶体团簇较小,分散性更好, Cu(II)还原程度更高.添加CeO2的吸附剂样品5Ce50Cu(CeO2和CuCl2的质量分数(w)分别为5%和50%)获得了最好的吸附分离效果,相对于未添加CeO2的样品50Cu,其在660 kPa下的吸附选择性由4.2提升到8.7.

关键词: C2H4, 变压吸附, 吸附选择性, CeO2助剂, Cu(I)活性位, 表面表征

Abstract:

CeO2 promoted CuCl/activated carbon (AC) adsorbents were prepared using an incipient wetness impregnation method, and characterized using N2 adsorption/desorption isotherms, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The Cu(II) on the AC surface was reduced to Cu(I) when calcination was performed in a nitrogen flow. The effects of Ce on the C2H4/C2H6 adsorptive separation performance were investigated. The adsorption isotherms showed that the addition of CeO2 improved the separation performance by decreasing the C2H6 adsorption capacity compared with that of the nonpromoted sample. The XRD and XPS results indicated that the active crystal particles on the AC surface became smaller, leading to higher dispersion and a higher degree of Cu(II) reduction. The best adsorption selectivity was obtained using the 5Ce50Cu [CeO2 and CuCl2 mass fractions (w) 5% and 50%, respectively] sample, i.e., with CeO2 in the adsorbent; the adsorption selectivity increased from 4.2 to 8.7 at 660 kPa compared with that of the 50Cu sample.

Key words: C2H4, Pressure swing adsorption, Adsorption selectivity, CeO2 promoter, Cu(I) active site, Surface characterization

MSC2000: 

  • O647