METHOD FOR DETERMINATION OF SILICON BY ELECTROTHERMAL ATOMIC ADSORPTION SPECTROMETRY Russian patent published in 2021 - IPC G01N21/71 G01N33/18 

FIELD: chemistry.

SUBSTANCE: invention relates to the field of analytical chemistry and can be used to determine the dissolved forms of silicon by enterprises and institutions carrying out quality control, and to study drinking, natural and waste water, water extracts from products made on the basis of polymer, closures and other materials. The method for determining the mass concentration of dissolved forms of silicon by the method of electrothermal atomic absorption spectrometry according to the invention consists in the fact that at least 250 cm³ of water is taken into a plastic container, the analyzed water samples are filtered through a "blue ribbon" filter immediately after taking them. In this case, the determination of the mass concentration of silicon is carried out in the filtrate by the method of electrothermal atomic absorption spectrometry (ETA - AAS). The ETA - AAS method includes the use of an atomic absorption spectrometer, the use of graphite cells with transverse heating, preliminary chemical separation of sample components after precipitation of sulfate ions by stoichiometric introduction of a 10% barium nitrate solution into the analyzed water sample, creation of a protective coating for a graphite furnace made of refractory tungsten carbide at the sample dosing point, the use of a chemical modification for thermal stabilization of silicon in the furnace in the presence of a mixed palladium-magnesium modifier in the nitrate form, elimination of matrix ions in the sample after adding an excess of iron nitrate with a mass concentration of 0.07 mol / dm³ (for iron) into a graphite furnace, temperature-time heating program, detection at a wavelength of 251.611 nm and quantitative determination of the analyte according to a previously constructed calibration curve.

EFFECT: invention provides possibility of selective, high-precision determination of the mass concentration of silicon, using widespread equipment.

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