Development of an original and easy method for Isocyanic acid (HNCO) calibration on FTIR Spectrometer

• Published in: Vibrational spectroscopy Vol. 116; p. 103290
• Main Authors: Gibier, Maximilien, Girods, Pierre, Rogaume, Yann
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2021; Elsevier
• Subjects: Chemical Sciences; Cyanuric acid; FTIR calibration; Infrared spectroscopy; Isocyanic acid; Organic chemistry; Pyrolysis; Cyanuric acid; Infrared spectroscopy; Pyrolysis; FTIR calibration; Isocyanic acid
• ISSN: 0924-2031; 1873-3697
• DOI: 10.1016/j.vibspec.2021.103290

•Degradation of cyanuric acid for the production of isocyanic acid.•Original method to perform a calibration of isocyanic acid (HNCO) for Infra-Red spectrometry.•Production in well-known quantities for a precise and quite easy calibration. HNCO is a harmful gaseous molecule presents in atmosphere and in many gaseous effluents such as automobile exhaust gases and waste biomass burning processes. Nevertheless, no commercial standard gas is available making analyzers calibration impossible, for FTIR spectrometry which is the most common method used for on-line measurements of isocyanic acid. The release of HNCO from the depolymerization of cyanuric acid by pyrolysis at 450 °C and 550 °C has been investigated, using a tubular reactor coupled with an infrared spectrometer. Under these conditions, gaseous HNCO is the major product (50 % < HNCO < 80 %), all other gas species (CO2, CO, NH3) being identified and well quantified. The coefficient of a cubic calibration equation between HNCO area FTIR spectrum and HNCO gas content are calculated by assuming the same quantity of HNCO given by mass balance and by FTIR measurement. Additional tests were performed to assume the reliability of the performed calibration.