CO2 containing plasmas are of growing interest for greenhouse gas remediation and dry gas reforming. In this paper, we show that the optical emission spectrum of CO(B-A) transition can be used for gas temperature determination in CO2 containing plasmas. The study was performed in a packed-bed reactor and compared with previously published results for a MW discharge. The CO emission is mainly produced by direct electron excitation from ground state CO. The rotational temperature is determined by a fitting algorithm of the CO(B-A) (0-1) spectrum and the accuracy of the deduced rotational temperature is shown to be better than 30 K. Meanwhile, we also compared the results with the widely used Boltzmann plots of the CO(B-A) (0-1). The rotational lines corresponding to Q(18–24) yield accurately the gas temperature for spectra with a resolution in excess of 0.05 nm FWHM. Rotational lines with N < 18 cannot be used due to the overlap of rotational lines from different branches unless a spectral resolution of at least 5 pm is used.
Bibliographical noteFunding Information:
This work is supported by the University of Minnesota and Tokyo Institute of Technology. S. Moore acknowledges funding from the NSF EAPSI program for US graduate students in Science and Engineering and Y. Du acknowledges funding from the China Scholarship Council. The authors thank T. Silva for providing a CO spectrum from his MW plasma source.
© 2016, Springer Science+Business Media New York.
- CO Angstrom system
- CO containing plasma
- Dielectric barrier discharges (DBD)
- Gas temperature determination
- Rotational spectroscopy
- Spectrum fitting