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Title: Raman spectral behavior of N 2 , CO 2 , and CH 4 in N 2 –CO 2 –CH 4 gas mixtures from 22°C to 200°C and 10 to 500 bars, with application to other gas mixtures

The Raman spectral behavior of N2, CO2, and CH4in ternary N2–CO2–CH4mixtures was studied from 22°C to 200°C and 10 to 500 bars. The peak position of N2in all mixtures is located at lower wavenumbers compared with pure N2at the same pressure (P)–temperature (T) (PT) conditions. The Fermi diad splitting in CO2is greater in the pure system than in the mixtures, and the Fermi diad splitting increases in the mixtures as CO2concentration increases at constantPandT. The peak position of CH4in the mixtures is shifted to higher wavenumbers compared with pure CH4at the samePTconditions. However, the relationship between peak position and CH4mole fraction is more complicated compared with the trends observed with N2and CO2. The relative order of the peak position isotherms of CH4and N2in the mixtures in pressure–peak position space mimics trends in the molar volume of the mixtures in pressure–molar volume space. Relationships between the direction of peak shift of individual components in the mixtures, the relative molar volumes of the mixtures, and the attraction and repulsion forces between molecules are developed. Additionally, the relationship between the peak position of N2in ternary N2–CO2–CH4mixtures with pressure is extended to other N2‐bearing systems to assess similarities in the Raman spectral behavior of N2in various systems.

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Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Raman Spectroscopy
Page Range / eLocation ID:
p. 750-769
Medium: X
Sponsoring Org:
National Science Foundation
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