Analysis of the temperature and pressure dependence of the 129Xe NMR chemical shift and signal intensity for the derivation of basic parameters of adsorption as applied to zeolite ZSM-5.
Temperature and pressure dependences of the 129Xe NMR chemical shift and the signal intensity have been investigated using ZSM-5 as an adsorbent under routine conditions without using any high-pressure or especially high-temperature facilities. The use of a rigorously shielded system and a calibration sample for the signal intensity was found to be valuable to obtain reliable data about the chemical shift and the signal intensity. The 129Xe NMR data obtained between 0.05 and 1.5 atm and from 24 to 80 degrees C were analyzed based on the Dubinin-Radushkevich equation as well as the Langmuir type equation. In both analyses, chemical shift data succeeded only partially in providing the profile of adsorption, such as energetic aspects, surface area, saturated amount of Xe adsorption and specific parameters of 129Xe chemical shift. It was shown that the reliable total analysis was achieved when the chemical shift data were used together with the intensity data. Such an analysis of the chemical shift data, aided by the intensity data, will be useful in performing nano-material analysis on 129Xe NMR without invoking the traditional methodology of gravimetric or volumetric adsorption experiments.
Kawata
Yoko
Y
Division of Health Sciences, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita, Osaka 565-0871, Japan.
Adachi
Yuko
Y
Haga
Saori
S
Fukutomi
Junko
J
Imai
Hirohiko
H
Kimura
Atsuomi
A
Fujiwara
Hideaki
H
D000327:Adsorption; D000465:Algorithms; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D015233:Models, Statistical; D036103:Nanotechnology; D011312:Pressure; D013696:Temperature; D013816:Thermodynamics; D014979:Xenon Isotopes / Q000737:chemistry*; D017641:Zeolites
D007202:Indicators and Reagents; D014979:Xenon Isotopes; D017641:Zeolites