Study of pressure broadening effects of H2 on CO2 and CO in the near infrared region between 6317 and 6335 cm−1 at room temperature

- H2 pressure broadening coefficients of CO and CO2 in the region between 6317 and 6335 cm−1 for room temperature was studied.
- H2 pressure broadening coefficients of CO2 are presented.
- The pressure broadening effect of H2 on CO was found to be insignificant for industrial TDL measurements.
- An estimate of the H2 broadened halfwidth in CO is given.

In this absorption spectroscopy study of CO2 and CO in the near-infrared (NIR) region between 6317 and 6335 cm−1, we focus on the broadening effect of H2 at room temperature (296 K). Absorption spectra were collected using a Tunable Diode Laser (TDL) operating in the NIR for various gas mixtures filled in a monel gas cell. The experimental parameters chosen in this study are highly relevant to combustion-related industrial applications where TDL sensors are employed to monitor CO2 and CO emissions. In many such applications H2 is always present and there is a need to understand the broadening effect of H2 on CO2 and CO to improve the detection quality of such sensors. Voigt profile analysis was performed to retrieve the experimental parameters. CO2-H2 broadening coefficients are presented for room temperature. From our study on the CO-H2 broadening effect at room temperature, we conclude that within the sensitivity of the measurements made, the presence of H2 has no significant effect in this region. The parameters calculated in this study are intended to be an addition to spectroscopic databases such as HITRAN.