NEW APPROACHES ON GAS-PHASE MOLECULAR ABSORPTION SPECTROMETRY DETECTION IN GAS-CHROMATOGRAPHY

A hyphenated technique for coupling a spectrophotometric detector to a gas chromatograph with a packed column is described. The packed colum n was connected directly to the flow cell (path length 1 cm) which was placed in a UV-visible molecular absorption spectrophotometer with di ode array detector. This detection system was employed for separating and determining benzene, toluene, 1,4-xylene, 1,2-xylene and mesitylen e. Molecular absorption spectra of all the separated compounds have al so been obtained. A new possibility for coupling capillary gas chromat ography and gas phase molecular absorption spectrometry is currently b eing tested. In this new case, two fibre optics are used and the measu rement is performed in the capillary column.