Detection of H2S, SO2 and NO2 in CO2 at pressures ranging from 1-40 bar by using broadband absorption spectroscopy in the UV/VIS range

This paper presents a methodology to quantitatively measure H2S, SO2 and NO2 fractions in gaseous CO2 by using broadband absorption spectroscopy at 1 and 40 bar. The mole fractions of binary- and 3-component mixtures of H2S, SO2 and NO2 in CO2 with known fractions ranging from 35-250 ppm are successfully derived from the measured absorption spectra. The difference between the fitted and experimental mole fractions is less than 10% for all studied mixtures. The results successfully demonstrate that low fractions of H2S, SO2 and NO2 in gaseous CO2 can be accurately measured at pipeline conditions by using broad band absorption spectroscopy.