Abstract

The effect of various experimental and instrumental parameters on the quantitative analysis of mineral oil components by means of infrared (IR) spectrometry has been investigated. Standard NEN-methods 6675 en 5733 have been used as starting point. Experiments have been carried out in parallel on a dispersive and a Fourier-Transform infrared spectrometer and results have been compared. The influence of the solvents carbontetrachloride, 1,1,2-trichlorotrifluoroethane (freon-113) and tetrachloroethene on the linearity, reproducability and detection limits have been determined. Factors affecting the analysis appear to be solvent, evaporation effects, pipet-type, cell-type, cell position, instrument-type and optical resolution. Detection limits in freon-113 and carbontetrachloride on the Fourier-Transform instrument are found to be about 0.2 mug/l ; a factor of 3 better than on the dispersive machine. Tetrachloroethene was found to be less suited as a solvent. Recommendations are made to improve the present standard procedures.