Raman and DFT Study of the H₂S Scavenger Reaction of HET-TRZ under Simulated Contactor Tower Conditions

Raman spectroscopy is a rapid and noninvasive analytical technique used for the analysis of complex materials in complex matrices. Herein, we report for the first time a combined Raman-DFT study to assign all the vibrational modes associated with the most important species involved in the H2S scavenger reaction of HET-triazine under simulated contactor tower conditions. In doing so, we have defined specific peaks or Raman identifier bands (RIBs) to get a complete reaction profile of the H2S removal process. Our methodology was able to identify the presence of the elusive 2,2′-(1,3,5-thiadiazine-3,5-diyl)di(ethan-1-ol) (TDZ) intermediate and also provided evidence supporting the formation of the sulfur polymeric deposit from the 2-(1,3,5-dithiazinan-5-yl)ethan-1-ol (DTZ) byproduct.