• 中文
    • English
  • English 
    • 中文
    • English
  • Login
View Item 
  •   DSpace Home
  • 化学化工学院
  • 化学化工-已发表论文
  • View Item
  •   DSpace Home
  • 化学化工学院
  • 化学化工-已发表论文
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Copper sites in copper-exchanged ZSM-5 for CO activation and methanol synthesis: XPS and FTIR studies

Thumbnail
Full Text
Copper sites in copper-exchanged ZSM-5 for CO activation and methanol synthesis XPS and FTIR studies.htm (392bytes)
Date
1997-03-26
Author
Chen, HY
Chen, L
Lin, J
Tan, KL
Li, J
李军
Collections
  • 化学化工-已发表论文 [14469]
Show full item record
Abstract
Cu-ZSM-5 samples with various Cu+/Cu2+ ratios have been successfully prepared in three different methods and studied by XPS and FTIR. Cu+ ions are found, by XPS, to mainly exist in the samples prepared by solution ion exchange and microwave solid-state reaction exchange. On the basis of the chemical shift of the Al 2p core level to a higher binding energy [Al(species II)], with the atomic ratio of Cu+/Al(species II) being approximately one, and the vanishing of the IR band at 3640 cm(-1) due to copper exchange, it is suggested that Cu+ ions locate in the open channels of the ZSM-5 framework and bind to mixed (Si- and Al-) bridged oxide ion. From the ZSM-5 pore structure consideration, as well as from the observed decrease in the IR intensity ratio of bands 550/450 cm(-1) with enhanced Cu2+ loading, it is also suggested that Cu2+ ions are a predominant Cu species in solid-state reaction exchanged Cu-ZSM-5 samples and exist as a CuO cluster in small cages as well as in open channels. The IR bands at 907 and 964 cm(-1) are identified as zeolite asymmetric internal vibration perturbed by exchanged CU2+ and Cu+ ions, respectively. Cu ions in Cu-ZSM-5 samples can be reduced to Cu-0 by CO adsorption at room temperature. The IR bands at 2128, 2158, and 2176 cm(-1) are observable and ascribed to the CO adsorbed on Cu-0, Cu+, and Cu2+ sites, respectively. Methanol formation from syngas over Cu-ZSM-5 is observed at 250 degrees C and 2 MPa.
Citation
INORGANIC CHEMISTRY,1997,36(7):1417-1423
URI
http://dx.doi.org/doi:10.1021/ic960122l
https://dspace.xmu.edu.cn/handle/2288/13548

copyright © 2002-2016  Duraspace  Theme by @mire  厦门大学图书馆  
About | Policies
 

 

Browse

All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

My Account

LoginRegister

copyright © 2002-2016  Duraspace  Theme by @mire  厦门大学图书馆  
About | Policies