Benzene detection by absorbance in the range of 20 ppb-100 ppb Application: Quality of indoor air

摘要

In the framework of a French Joint program COVADIS, an innovative system is developed for the simultaneous detection of benzene, toluene and xylenes in indoor air. The present work is mainly focused on the benzene detection. The detection is based on absorbance measurements over the 250 nm-300 nm range with a cooled spectrophotometer. The prototype includes an exposure chamber, which contains five sensors. The sensors are nanoporous disks, whose pore sizes are tailored to efficiently entrap the targeted pollutants. 20 ppb of benzene have been successfully detected within 40 minutes of exposure.