Détection spectrophotométrique en temps réel d'hydrocarbures monoaromatiques (benzène, toluène et xylènes) dans l'air aux valeurs limites d'exposition professionnelle

The objective of this thesis was to develop a spectrophotometric sensor to quantify benzene, toluene and xylenes (BTX) in real time at the level of the occupational exposure limit values, ie 20 ppmv for toluene, 50 Ppmv for xylenes and 1 ppmv for benzene. The study was carried out with several sensitive layers, a solid silicic material synthesized by the sol-gel process or thin films (less than 5 μm) deposited on quartz by dip-coating a suspension of nanoparticles or a precursor solution leading to mesoporous silica thin films. We were able to demonstrate the effectiveness of BTX detection in real time. The use of continuous mesoporous films has enabled a correct repeatability of the sensor (standard deviation