SU1422074A1 - Method of preparing samples-radiators for x-ray fluorescent analysis of metals - Google Patents

Abstract

This invention relates to analytical chemistry, in particular to methods for preparing samples from. Part 1 is for the X-fluorescence analysis of meta.huv, and can be used to reduce the detection and new precision of the rapid analysis of toxic meta parts in environmental objects and meat and dairy products. For this, an aliquot portion of the test solution containing 0.0025 g Cu (I) is placed in a heat-resistant extraction vessel. Using dilute ammonia and nitric acid solutions, the pH is adjusted to an equilibrium value of 7.2. The vessel is placed in a water bath equipped with a booster tube. Heated to 70 ° C, and 2.0 g of the primary acid of the fraction C are introduced;; Juice. After the extractant has been melted, shaking is performed for 3 minutes. The contents of the beaker are cooled to room temperature, the solidified organic mass is separated from the aqueous phase, and placed on the filter. The extract is then melted in a box, copiously transferred into a ring-holder and x-ray measurements are carried out after solidification. Reach nrede.ch Obu | ) already 5-10-% (L 4; o 1 hE O

Description

The invention relates to analytical chemistry, in particular, to methods for preparing emitter samples for X-ray fluorescence analysis of metals, and can be used for the rapid analysis of toxic metals in the environment and products of the meat and dairy industry.

The purpose of the invention is to reduce the detection limit and increase reproduction; bridges of determination .10

Example. An aliquot portion of the solution being analyzed, containing, its 0.0025 g Cu (II), held in a heat-resistant extraction vessel. Using dilute ammonia and nitric acid solutions, the pH is adjusted to an equilibrium value of 7.2. The vessel was agitated, placed in a water bath equipped with a shaking device, heated to 70 ° C, and 2.0 g of primary aliphatic alcohols of the C & Cji fraction were introduced. After

water analysis results. The use of alcohols with more than 21 carbon atoms is inefficient, as the extraction capacity of the extractant decreases, which leads to a decrease in metal recovery and an increase in the detection limit.

Conducted experiments to determine the content of Cu (I) using the fraction of Ci6-C21 primary aliphatic alcohols, depending on temperature, show that no extraction of metals takes place below 60 ° C, since the extractant does not melt. When carrying out the extraction at a temperature above 95 ° C, the solution evaporates, which leads to irreproducibility of the results.

In tab. 2 shows the experimental results for the determination of the Cu (II) content as a function of the pH of the aqueous phase using the fraction

table 2

melting of the extractant produced up to 20 primary aliphatic alcohols chihanie for 3 minutes. The contents of the stage and the extraction temperature of 80 ° C.

The channel is cooled to room temperature, the solidified organic phase is separated from the water by filtration and dried on the filter. Then the extract is melted in a box, quantitatively transferred to the ring-holder, and after hardening X-ray spectral measurements are taken. The detection limit is 0.05 mg / L (). In tab. 1 shows the results of experiments to determine Cu (II) depending on the carbon chain length of the aliphatic alcohols at an extraction temperature of 78 ° C.

Table 1

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water analysis results. The use of alcohols with more than 21 carbon atoms is inefficient, as the extraction capacity of the extractant decreases, which leads to a decrease in metal recovery and an increase in the detection limit.

Conducted experiments to determine the content of Cu (I) using the fraction of Ci6-C21 primary aliphatic alcohols, depending on temperature, show that no extraction of metals takes place below 60 ° C, since the extractant does not melt. When carrying out the extraction at a temperature above 95 ° C, the solution evaporates, which leads to irreproducibility of the results.

In tab. 2 shows the experimental results for the determination of the Cu (II) content as a function of the pH of the aqueous phase using the fraction

  primary aliphatic alcohols and an extraction temperature of 80 ° C.

table 2

25

thirty

As follows from the results presented in table. 1, the use of primary aliphatic alcohols with the number of carbon atoms less than 16 does not allow to achieve the required reproducibility and detection limit of Cu (II), since the emitter samples obtained in this case are an unstable and inhomogeneous matrix, which leads to a non-reproducible I'll do it under optimal conditions

0.112-0.22 1-10

Thus, according to experimental data, when using extractant of the fraction of Ci6-C21 primary aliphatic alcohols at a pH of the aqueous phase of 6.4-8.6 and carrying out extraction at 65-90 ° C, the detection limit is reduced by half and -8 times

Claims (1)

Invention Formula Method of preparing emitter samples for X-ray fluorescence detection 314220744 leaching metals by treating the water flow of the anals, extracting the solution with melt extractant, melting by treating the solution with melt of the primary solid extract, pouring a Cie-Czi fraction into the forming aliphatic alcohols, characterized in that with the aim of equilibrium pH 6.4-8.6 and temperature - lowering the detection limit and increasing the range of 65-90 ° C.