SU1100524A1 - Method of producing concentrate of selenium microquantities - Google Patents

Description

1 The invention relates to analytical chemistry, and specifically to methods for producing a microcolchium selenium concentrate by co-precipitating it with a strongly acidic diluted collector. solutions and can be used in the analysis of industrial wastes, soils, plant objects, natural and waste waters. A known method for producing a selenium concentrate for the subsequent analytical determination by coprecipitating it with a collector from strong solutions, concluded that selenium was extracted from a solution of 10% hydrochloric and sulfuric acid with a volume of 100 ml in the presence of 100 µg tellurium using chloride tin and hydrazine are added to the pulp and the solution with the precipitate is boiled for 2-3 minutes, the precipitate is filtered off after 10-15 hours and the selenium content in it is determined by 3, 3-diaminobenzidine Q. The disadvantages of this method are the duration, the lack of sensitivity (dilution of 1: 210), the low degree of recovery of selenium from solution (70-85%) and the use of toxic tellurium. The closest in technical essence and the achieved result to the invention is a method for producing a concentrate of selenium by coprecipitation with a collector from highly acidic dilute solutions, which concludes that selenium is separated from 6 M hydrochloric acid solution: containing 10 ml of sulfuric acid (1: 1), 0.1 g of copper sulfate and 1 mg of mouse for every 100 ml of solution, sodium hypophosphite is reduced, the solution with precipitate is added after boiling for 10 minutes, the precipitate is filtered off after 10-15 hours and the selenium content is he determined 3, 3-diaminobenzidine 2}. However, for the known method, characterization duration is not enough for sensitivity (dilution is not more than 1: 1 10 °) and the use of a toxic mouse. The purpose of the invention is to increase the sensitivity of the determination of selenium and reduce the time of analysis. This goal is achieved by the fact that, according to the method for producing a concentrate of microquantities of selenium, including coprecipitation with a collector of highly acidic dilute solutions, the iodide salt of the basic dye bis- (4-methylbenzylaminophenyl) -antipyrnsh1 carbinol is used as a collector. A distinctive feature of the method is that the iodide salt of the basic dye bis-A-methylbenzylaminophenyl / -antipyrylcarbinol is used as a collector. Selenium in a sulfate (0.25-0.5 M) medium in the presence of iodide ions forms a sparingly soluble compound with the reagent, which, together with the dye iodide precipitate, precipitate, filter, and the precipitate is analyzed for selenium content in it using a suitable instrumental method. The proposed method was tested when analyzing soil samples with varying degrees of dilution of sample solution from 1: 1.-10. In tab. 1 shows the metrological data (calculated on the basis of two parallel measurements at a dilution of 1: 2-10). Split of selenium from dilute solutions of bis- / 4-methylbenzylaminophenyl / antipyrylcarbinol collector iodide, moreover, the weighed amount is 1 g; , 95: t, 4.3. When diluted to 1: 1, the metrological characteristics of the proposed method do not significantly change. In tab. 2 presents the comparative characteristics of the prototype and the proposed, methods at a dilution of 1: 2-10; , 85; 3 Example. The analyzed sample is decomposed, transferred into a solution so that its acidity is 0.1 M in addition, a 1.5 M solution of potassium iradide is added until its concentration in the in-analyzed solution is 0.12 M and slowly with stirring, 1 O M is added dye solution at 0.5 M to its concentration in a solution of 3 10M. After 30 minutes, the precipitate which has entered is filtered off through a medium-density white ribbon filter using a separable funnel. The precipitate is washed with a washing liquid (3-5 ml of a 1.5 M solution of potassium iodide and 5 ml of a 510 M solution of reagent are added to 500 ml of a 0.2 M H2SO2 solution), dried under an IR lamp and placed in a teflon ring

311005244

The surface is covered with a copper wire through the same stages with an analyte film no thicker than 4 microns. , for, as the sample. The selenium content in the sediment is determined. The invention improves the sensitivity of the determination of selenium using an X-ray fluorescence method. The standards are prepared using 5 (1: 1 dilution) and reduce the precipitation of known amounts of selenium during the analysis (up to 1-2 hours).

Table

9.4il, 4 9.9 0.51 0.05 9.5

Characteristic

Prototype

0.01 18

4.8 ± 0.9 Entered 5 mcg

Cxp 1.0

Reproducibility,%

Table 2

Ways

I

Proposed

0.001 16 9.7 ± 1.6

Attastov, the content of 9.4 µg

Chkep. 082 5 9.7 ± 1.6 0.82

Claims (2)

FLOOR METHOD CONCENTER IYA543.056 (088.8) 1. Guryev S. D., Blyakhman A. A., teach. Proceedings, No. 19, M., Metal (21) (22) (46) (72) (71) here (53) (56) Lutchenko N.N. Sat . Gintsvetmeta. 1962 Lurgizdat, p. 661 2. Voronkova M.A., Sidorenko G.A. Journal of Analytical Chemistry. 1967, t. 22, c. 7, p. 1085-1087. THAT OF MICRO QUANTITIES OF SELENIUM by coprecipitation with a collector from strongly acidic dilute solutions, mainly for subsequent analytical determination, distinguished by the fact that, in order to increase the sensitivity of determination of selenium and reduce the analysis time, iodide salt of the main dye is used as a collector bis- (4-methylbenzylaminophenyl) antipyrylcarbinol. 1 1100524 2