SU1281997A1 - Method of determining 2,4,6 - trinitrophenol - Google Patents

Abstract

This invention relates to analytical chemistry, in particular, to a method for determining 2,4,6-trinitrophenol. The aim of the invention is to increase the sensitivity, selectivity and accuracy of determination. The method is carried out as follows. The sample to be analyzed is dissolved in water and chromatographed on pretreated paper. The paper is treated with a 0.01-0.02% solution of potassium permanganate. Chromatography was carried out in a mixture of nonyl and ethyl alcohols, taken in a volume ratio (2-4): 1. The content of the substance is determined by the height of the resulting peak. The method does not require complex instrumentation. The sensitivity of the method is 1.5 µg / sample, the error in determining 2.1%. The method allows the determination of 2,4,6-trinitrophenol in the presence of o-nitrobenzoic acid. 2 tab. i (Л С

Description

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The invention relates to analogue chemistry, in particular to the chromatographic determination of 2,4,6-trinitrophenol (2,4,6-TNF) in the presence of 0-nitrobenzoic acid.

The aim of the invention is to increase the sensitivity, accuracy and selectivity of the determination.

Example 1. To build

A capillary with a capacity of 0.0015 ml applied 3-5 samples to the chromatographic paper next to the samples to build a calibration graph (example 1). The chromatographic plot of the chromatographic screen is immersed in a mixture of nonyl and ethical paper and impregnated with a 0.01% KMniD solution. The paper is dried in air, leveled under pressure. 10 samples of solutions containing 2,4,6-TNF 1,50 are applied to the starting line; 5 3.0; 4.50; 7.50 and 9.0 mcg in the sample (2 samples of each concentration, the volume of the sample is 0.0015 ml). The chromatogram is lowered to the line of immersion in a mixture of nonyl and ethyl alcohols in a 3: 1 ratio, which is in a chromatographic cell. After the chromatogram has been developed, peak heights are measured using the smallest calibration curve method. According to the results of the analysis, data are calculated for the construction of a calibration graph.

Experimental and calculated data20

3: 1 alcohol up to the dip line. After raising the liquid phase, the chromatogram is sampled and peak heights are measured. The average value of the peak height is determined by the content of 2,4,6-TNF in the sample, using a calibration graph calculated by the least squares method.

Experimental data are given in table 2.

Table 2

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The data are presented in Table 1.

Example 2. A solution of 2,4,6-TNF is prepared for the analysis of the sample of samples, 75-100 mg are dissolved in water in a 25 ml volumetric flask (in the example, weighed 100.0 mg, the concentration of the analyzed solution is 4 mg / ml)

Table 1

Chromatography paper is impregnated with a 0.01% KMnQ solution.

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dried and leveled under the press.

A capillary with a capacity of 0.0015 ml applied 3-5 samples to the chromatographic paper next to the samples to build a calibration graph (example 1). The chromatogram of u is immersed in a mixture of nonyl and these

3: 1 alcohol up to the dip line. After raising the liquid phase, the chromatogram is sampled and peak heights are measured. The average value of the peak height is determined by the content of 2,4,6-TNF in the sample, using a calibration graph calculated by the least squares method.

Experimental data are given in table 2.

Table 2

Example 3. Chromatographic paper was impregnated with 0.02% KMPO solution, dried and leveled under pressure.

3-5 samples of 2,4,6-TNF are applied to the start line with a capillary with a capacity of 0.0015 ml with samples designed to build a calibration graph (preparation of the solution of Example 2). After chromatography in a mixture of nonyl and ethyl alcohols 3: 1, the chromatogram is dried and peak heights are measured. The mean value of the height of the peaks is determined by the content of 2,4,6-TNF (6.01 µg / sample).

Example 4. Chromatographic paper is impregnated with 0.01% KMp04 solution and prepared for analysis.

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A capillary applied 3–3 samples of the analyzed 2,4,6-TNF solution next to the samples intended for the construction of a calibration graph. For this, a 2,4,6-TNF sample to be analyzed is 100.0 mg dissolved in water. measuring flask of 25 ml. After chromatography in a nonyl ethyl solution of 3: 1, the chromatogram is dried and peak heights are measured. The mean value of the peak height is calculated for the content of 2,4,6-TNF in the sample (5.98 µg / sample).

Example 5. For the study of the effect of non-alcoholic and ethyl alcohols on the analysis results, chromatographic paper was impregnated with a 0.015% KMp04 solution and prepared for analysis. 3-5 samples of 2,4,6-TNF are applied to the start line (preparation of a solution according to Example 2), chromatographed in a 2: 1 nonyl ethyl solution, and peak heights are measured. The mean value of 2,4,6-TNF in the sample (6.04 µg / sample) is calculated by the mean value.

Example 6. A chromatogram is impregnated with a 0.015% solution of KMpOd.

and prepared for analysis. 3-5 caps of 2,4,6-TNF are applied to the start line (preparation of the solution of Example 2). Chromatographic in a nonyl ethyl 4: 1 solution and measure peak heights. The mean value of 2,4,6-TNF in the sample (5.98 µg / sample) is calculated by the mean value.

Example 7. To investigate the effect of o-nitrobenzoic acid (o -NBK), a mixture was prepared with a content of 2,4,6-TNF io-NBK equal to 1: 1 (taken sample containing 100.0 mg 2.4, 6- TNF and 100.0 mgO-HBK). A portion of the mixture was dissolved in 5 MP of acetone in a 25 mL volumetric flask and made up to the mark with water.

Chromatographic paper was impregnated with a 0.015% solution of CMO and prepared for analysis. 3-5 samples of a solution of 2,4,6-TVF (with a solution of Example 2) and 3-5 samples of a solution of a mixture are applied to the start line of the capillary. After the chromatogram was immersed in a 3: 1 nonyl ethyl solution and the chromatogram was dried, peak heights were measured. The mean values of the peaks of both series determine the content of 2,4,6-TNF, pol

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by the calculated calibration schedule. The average height of the peaks 2,4,6-TNF. and in the mixture, respectively, 18.8 and 18.9 mm, which corresponds to the content of 2,4,6-TNF 5.98 and 6.01 µg / sample. The determination error does not exceed 2.1%.

Consequently, the admixture of o-NBC, up to a 100% excess, does not interfere with determining the content of the basic substance with an established error.

Example 8. Chromatographic paper FN-3 is impregnated with 0.0210% KMPO (4, dried and leveled under a press.

3-5 samples of 2,4,6-TNF are applied to the start line with a capillary with a capacity of 0.0015 ml with samples designed to build a calibration graph (preparation of the solution of Example 2, concentration of test solution 4.0 mg / ml) . After chromatography in a 3: 1 nonyl ethyl solution, the chromatogram is dried and the height of the peaks is measured (on a light gray background, the yellow peaks of 2,4,6-TNF). The mean value of the peak height is determined by the content of 2,4,6-TNF, using the calculated calibration curve. Its content is 5.56 µg / sample (average peak height is 17.5 mm, error of determination is 13%).

Example 9. Chromatographic paper was impregnated with a 0.009% solution of CMO and prepared for analysis.

3-5 samples of the analyzed 2,4,6-TNF solution are applied to the capillary rum next to the samples intended for the construction of a calibration graph. For this, a solution of 2,4,6-TNF 4.0 mg / ml is prepared (preparation of a solution according to example 2). After chromatography in a 3: 1 nonyl ethyl solution, the peak heights are measured. In this case, the peaks of the peaks are slightly colored and difficult to mark.

Example 10. Chromatographic paper was impregnated with a 0.015% solution of CMO and prepared for analysis.

3-5 samples of 2,4,6-TNF are applied to the starting line of the capillary (preparation of the solution according to example 2). Chromatographic in a 1: 1 nonyl ethyl solution and measure peak heights. In this case, the peaks of the peaks are blurred and practically not noted.

Example 11. Paper is impregnated with a 0.015% KMPO solution and prepared for analysis.

3-5 samples of 2,4,6-TNF (preparation of the solution of Example 2, concentration of the test solution of 4.0 mg / ml) are applied by a capillary rum, chromatographic in a nonyl alcohol solution of 5: 1, peak heights are measured. The mean value of the peak height is calculated for the content of 2,4,6-TNF, using the calculated calibration curve. Its content is 5.59 µg / sample (average peak height is 17.6 mm, error 12%).

Thus, the proposed method does not require complex instrumentation and as a micromethod requires low reagent costs. The sensitivity of its 1.5 µg / sample and chromatography were carried out in a mixture of 2.1%, and in the known alcohol and ethyl alcohols, the corresponding minimum values were determined in a volume ratio (2-4): 1.

The method for determining 2,4,6-trinitrophenol by dissolving the sample being analyzed, chromatographing on pretreated paper with subsequent determination of the substance content by the height of the forming peak, characterized in that, in order to increase the sensitivity, selectivity and accuracy of determination, water, paper is treated with a 0.01-0.02% solution of permangan, potassium, and

The chromatography was carried out in a mixture of nonyl and ethyl alcohols, taken in a volume ratio (2-4): 1.

the concentration was 5 µg / sample and the error in determination was 21%.

The proposed method is convenient for serial determination of 2,4,6-TNF in the presence of o-NBK.

Claims (1)

Invention Formula The method for determining 2,4,6-trinitrophenol by dissolving the sample being analyzed, chromatographing on pretreated paper with subsequent determination of the substance content by the height of the forming peak, characterized in that, in order to increase the sensitivity, selectivity and accuracy of determination, water, paper is treated with a 0.01-0.02% solution of permangan, potassium, and