Continuous on-line determination of methyl tert-butyl ether in water samples using ion mobility spectrometry

A rapid analytical procedure for the on-line determination of methyl tent-butyl ether (MTBE) in water samples was developed. A new membrane extraction unit was used to extract the MTBE from water samples. The concentration of MTBE was determined using ion mobility spectrometry with Ni-63 ionization and corona discharge ionization without chromatographic separation. Both ionization methods permit the sensitive determination of MTBE. A detection limit of 100 mu g/L was established for the on-line procedure. Neither the inorganic compounds, humic substances nor gasoline were found to exert a significant influence on the peak intensity of the MTBE. The screening procedure can be used for concentrations of monoaromatic compounds (benzene, toluene, xylene) up to 600 mu g/L. No sample preparation is required and the analysis results are available within 5 min. In order to determine concentrations between 10 mu g/L and 100 mu g/L, a discontinuous procedure was developed on the basis of the same experimental set-up. (c) 2004 Elsevier B.V. All rights reserved.