Experience in using ALPHA-VRA-30 software for determination of iron and zinc content in organometallic compounds and polymers

X-ray fluorescence analysis (XRF)based on a technique of direct external standard with the use of one reference sample is traditionally used in the laboratory of microanalysis (INEOS RAS) for determination of metals in composition of novel organometallic compounds and polymers. Preparation of the samples-emitters consists in 150 – 200-fold dilution of the substances with emulsion polystyrene (PS), since the amount of substance for analysis is limited to 10 – 15 mg. With this dilution XRF analysis are carried out in the concentration range of metal from 0.005 to 0.5 %, where the analytical calibration curve is linear. Measurements of analytical lines are carried out on a VRA-30 spectrometer (CARL ZEISS JENA (Germany)), X-ray tube with Rh-anode, 40 kV, 20 mA. A possibility of automatic conduction of X-ray fluorescence analysis of organometallic compounds and polymers synthesized in INEOS RAS on a VRA-30 spectrometer using software ALPHA-VRA-30 is studied. Software package developed at the research and innovation center JSC «FORATEKS» (Ekaterinburg) is intended for automated control of the spectrometer functioning without an operator. The software provides the possibility of deducing analytical equations of multiple regression on the basis of measurements of the intensities of analytical lines from the reference sample, and calculates the content of chemical elements in the analyzed samples-emitters. Advantages of the developed software are demonstrated and the results of XRF obtained using both the developed software and the method of direct external standard are compared. The small difference between the results obtained by those methods (0.7 % (abs)) in determination of iron and zinc in organometallic compounds when the content of iron and zinc range within of 4 – 25 % proves the applicability of the software to studying new compounds. Software ALPHA-VRA-30 provides standardization of measurement conditions and lightens the work of the analyst when analyzing large batches of substances.

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