QUANTIFICATION OF 2 CHROMATOGRAPHIC UNRESOLVED DICHLOROPHENOLS USING GAS-CHROMATOGRAPHY DIRECT DEPOSITION FOURIER-TRANSFORM INFRARED SPECTROMETRY AND MULTIVARIATE CALIBRATION

A method for the quantification of two chromatographically unresolved dichlorophenol isomers in water is described. Acetylation and concentr ation on graphitized carbon cartridges are carried out as a preliminar y step. Detection is made by gas chromatography (GC) coupled to Fourie r transform infrared spectroscopy (FTIR), using a direct deposition in terface (DD). Infrared spectra in the maximum of the unresolved peak o f 2,5- and 2,4-dichlorophenol for a series of standards with different amounts of these two compounds are used, to elaborate a multivariate calibration model (PLS-1 algorithm). By the method described, concentr ations of dichlorophenol isomers in water at ng/ml level can be determ ined.