Interlaboratory comparison of sulfur mass fraction in gasoline: MWDXRF spectrometry versus UV fluorescence

摘要

The authors' aims are to compare the performance of two test methods and participants' results with combined results from a group in the same round and limits determined by the variability of participant results. Moreover, this study can be considered as a tutorial; because stability, homogeneity and characterization tests related to interlaboratory comparisons are detailed. Sulfur mass fractions in three different samples of gasoline (with 26% anhydrous ethanol) are analyzed by ultraviolet fluorescence or monochromatic wavelength dispersive X-ray fluorescence spectrometry, by the participating laboratories. Applying robust statistical methods, the results show that there are systematic errors between both test methods.