|Proficiency Test on MTBE/ETBE finished
The full report can be downloaded (as .pdf-file). To download the report, please click the right mouse button and choose the "save as" option.
Summary of this proficiency test:
On 31 May 2010, the proficiency test on MTBE/ETBE (iis10C03) was finished. It started on 24 March 2010 (see message “Proficiency Test on MTBE/ETBE started” on this website) when the samples were distributed.
In this international interlaboratory study 23 participants in 14 different countries have participated on MTBE.
In this international interlaboratory study 18 participants in 11 different countries have participated on ETBE .
The participants were requested to determine:
Appearance, Water, Refractive index, Density @15C, Purity, Purity on dry basis and some GC- impurities: Diisobutylenes, Methanol, t-Butylalcohol, C4-, C5- and Other hydrocarbons on the MTBE sample and
Appearance, Water, Density @15C,
Sulphur, Nitrogen, Purity, Purity on dry basis and some GC- impurities:
Diisobutylenes, Ethanol, t-Butylalcohol, C4-, C5- and Other hydrocarbons on the ETBE sample.
The proficiency test report summarises per test, the test results, the analytical methods reported by the participants and the z-scores calculated by i.i.s. for each participant are tabulated. Also, for each test, the calculated summary (e.g. mean, standard deviation and reproducibility) is given.
In the report also an evaluation of the test results is given. Problems encountered in the analyses are mentioned and - where possible - suggestions for quality improvement are formulated. For each test a comparison is made between the results of the group of participants and the requirements given by the relevant standard (e.g. ISO, DIN, ASTM).
Interested parties can order a hard copy of the report; the price for non-participants is Euro 35.