METHOD OF MEASURING MASS CONCENTRATIONS OF NIOBIUM AND TANTALUM IN AIR OF WORKING ZONE BY MASS SPECTROMETRY WITH INDUCTIVELY COUPLED PLASMA

摘要

FIELD: chemistry.;SUBSTANCE: invention relates to analytical chemistry. Method of measuring mass concentrations of niobium and tantalum in air of a working zone by mass spectrometry with inductively coupled plasma, according to which sampling air of the working area is performed by drawing the analysed air through an analytical aerosol filter, at rate of 2–20 l/min for 30 minutes, recording air temperature and atmospheric pressure at sampling moment, filter is placed in quartz barrel and installed in muffle furnace, held for 1.5–2 hours at temperature of 400–450 °C, 1.0 g of potassium pyrosulphate is added, held at the same temperature until transition into a liquid state, then held for 10 minutes at temperature 800–850 °C, the sample is allowed to cool, 10 ml of 10 % aqueous tartaric acid solution and heating to produce a sand bath until dissolved, the sample is transferred to a volumetric flask and adjusted to the sample volume of deionized water to 100 cm³; 4.95 cm³ of the prepared sample is introduced into a test tube of an automatic sampler of a mass spectrometer, 0.05 cm³ of an internal standard is added with mass concentration of a terbium comparison element of 1000 mcg/dm³ and then, by inductively coupled plasma mass spectrometry, concentration of niobium and tantalum is determined using a calibration curve and taking into account the amount of air withdrawn for analysis to normal conditions.;EFFECT: invention provides the possibility of determining both niobium and tantalum in the working area at a level of from 0_00002 mg/m³ or higher.;1 cl, 10 tbl, 2 dwg