SU1078321A1 - Method of determination of butyphos and hexachlorcyclohexan in air - Google Patents

Abstract

A METHOD FOR DETERMINING BUTIFOSUS AND HEXAHLOROR CYCLOGEXANE IN AIR By passing air through an absorption solution (solvent-based), concentrating absorbed substances, followed by chromatographic analysis of the concentrate, o TL. And so that, in order to improve the accuracy of the method and the value of solvent consumption, a mixture containing, in wt.%: iH-hexane 5-35J surfactant 0.05-, is used as the absorption solution. 0.30; water up to 100, and the concentration of the absorbed substances are natalced with an absorption solution of sodium sulfate with S. SP

Description

This invention relates to analytical chemistry, in particular, to methods for the determination of the precursor chemicals of butyphos and hexachlorocyclohexane in air.

There is a known method for the determination of dohimicates in air by passing air through an absorption vessel with water, extracting it with chloroform, followed by chromatographic IMC analysis of the extract fij.

The disadvantage of this method is low accuracy.

The closest to the invention according to the technical essence and the achieved result is the method of determining butiphos and hexachlorocyclohexane in air by passing the latter through absorbing solution of ethylene glycol, diluting it with an aqueous solution of salt, reextracting the substance to be detected with hexane, concentration by evaporation followed by chromatographic analysis of the concentrate 22.

The disadvantages of this method are low accuracy, relative error (49% and high solvent consumption.

The purpose of the invention is perfection. method accuracy and reduced solvent consumption.

This goal is achieved by the fact that, according to the method, the determination of the bottle of phos and hexachlorocyclohexane in the air by passing air through the plotting solution, as a result, a mixture containing wt.%: N-hexane 5-35; surfactant (surfactant) 0.05 0.30; water up to 100, and the concentration of the absorbed substances lead to saturation of the sodium sulfate absorption solution.

Example 1. 4.6g of household soap shavings (MRTU 18/1033 is dissolved in 1 liter of distilled water (solution concentration 0.46%). In the cold; a high-capacity washing bottle (450 ml) is poured from a burette 53.0 ml (35.9 g) n-hexane brand CHP and 65.0 ml (65.0 g) of an aqueous solution of soap (emulsion composition, wt.%: Hexane 35.00; surfactant 0.30; distilled water else /.

Before sampling the air, the flask is shaken vigorously to form an emulsion. The analyzed air is pulled by an electroaspirator through an absorption tank at an aspiration rate of 1 l / min for 40 minutes. After sampling, excess (10 g) sodium sulfate (not less than 40 g) is added to the remaining sorbent (1 g of sorbent) and the contents are agitated. After settling, the absorbent is poured into a burette, rinsed with 5 MP distilled water and 5 MP waste water is drained into the same burette. After 5-10 minutes, the volume of the hexane layer is measured, the lower aqueous layer is drained, and the hexane end of the waste is collected in a flask with a ground stopper. A sample of 1-5 μl is introduced into the Gazokhrom-1109 chromatograph with an electron capture detector, with glass by the column 150x0,3 cm filled with N-AW-DMCS chromaton fraction 0.125-0.160 mm, silanized with DMCC and impregnated with 5% Si-SE-30, temperature of the evaporator column 220, detector thermostat 250. The device is pre-calibrated under similar conditions.

The results of determination of butifas in atmospheric air are given in Table. one.

Example 2. Determination of y-hexachlorocyclohexane (HHC / carried out as described in Example 1. The composition of the emulsion, wt.%; Hexane 5.00; surfactant 0.05; distilled water the rest.

The determinations are given in table. 2

In tab. Figure 3 shows the results of the evaluation of the sfshbki of each stage of the determination of bouyphos in atmospheric air according to the known and proposed methods with the calculation of the total error.

The relative error in the determination of pesticides by the proposed method is 6.1–6.4%, i.e. eight times {“less than the known method (49%). In this case, n-hexane solvent is required 25 times less. The detection time is reduced by 4-5 W, table 3

Hexane 49.1

Ethylene glycol 38.7 26.6 3-5

4.0

11.9

3.5

,

11.9

48.5

3.5

6.1-6.4

3.5

Claims (1)

METHOD FOR DETERMINING BUTYPHOSUS AND HEXACHLOROCYCLOHEXANE IN AIR By passing air through an absorption solution, based on a solvent, concentrating the absorbed substances, followed by chromatographic analysis of the concentrate, vol. characterized in that, in order to increase the accuracy of the method and reduce the consumption of solvent _f , a mixture containing, wt.%: IH-hexane 5-35} surfactant 0.05-0.30; water up to 100, and concentration of substances are absorbed the absorption saturation _with sodium sulfate. <g