FIELD: chemistry.
SUBSTANCE: invention relates to analytical chemistry and can be used by enterprises and organizations that carry out quality control of atmospheric air, when measuring styrene content in indoor air and atmospheric air. Claimed method for determining the styrene concentration in atmospheric air by high-performance liquid chromatography is that sampling atmospheric air by passing it through a sorption tube with a solid polymeric sorbent “Tenaks”. At the same time, air temperature and atmospheric pressure are fixed. Next, the extraction of styrene from the sorbent with acetonitrile is carried out and the obtained extract is analyzed on a liquid chromatograph with a fluorimetric detector. Concentration of styrene is determined using a calibration curve, taking into account the reduction of the volume of air sampled for analysis to normal conditions. Wherein, sampling of atmospheric air is carried out at a rate of 0.3 l/min for 30 minutes, and removal of styrene from the sorbent acetonitrile is carried out by passing the latter in a volume of 3 ml through a sorption tube. After extraction of the first portion in a volume of 1 ml and its evaporation to 0.5 ml, an extract is obtained. Analysis of the obtained extract on a liquid chromatograph with a fluorimetric detector is carried out using a mixture of water and acetonitrile in an initial ratio of 40:60 % by volume, respectively, at their varying ratio for 1 minute during the transmission of the mobile phase through the column from 4.5 minutes to 5.5 minutes to 100 vol% acetonitrile and to 0 vol% water, with further transmission of such a mobile phase for another 1 minute, followed by a reduction in the mobile phase of a volumetric amount of acetonitrile to 60 vol% and an increase to 40 vol% of water in 0.5 minutes, and passing such a mobile phase through the column for another 4 minutes. In this case, the above actions are carried out with a blank sample without an air sample. True concentration of styrene is determined from the difference in the data obtained for the air sample and the blank sample. Technical result is to increase the sensitivity and selectivity while ensuring the reduction of the detection limit of styrene to 0.000015 mg/m3.
EFFECT: increased sensitivity and selectivity.
1 cl, 4 tbl
