GOST 23687.2-79

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  ГОСТ 23687.2-79

GOST 23687.2−79 Ligature odnalezienia. Spectral method for determination of magnesium, iron, aluminum, silicon, lead (Change No. 1)

GOST 23687.2−79

Group B59

STATE STANDARD OF THE USSR

LIGATURE ODNALEZIENIA

Spectral method for determination of magnesium, iron, aluminum, silicon, lead

Alloy of copper-beryllium. Spectral method of the determination of maqnesium, iron, aluminium, silicon, lead

AXTU 1709*
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* Introduced advanced Edit. N 1.

Date of introduction 1980−07−01

Resolution of the USSR State Committee on standards of June 6, 1979 N 2050 expiration installed from 01.07.1980 to 01.07.1985*

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* Expiration removed by the resolution of Gosstandart of Russia from 21.10.92 N 1421 (IUS N 1, 1993). — Note the manufacturer’s database.

The Change N 1, approved and put into effect by the Decree of the USSR State Committee for standards from 27.09.84 N 3334 with 01.04.85

Change No. 1 made by the manufacturer of the database in the text IUS N 12, 1984


This standard specifies the spectral method for determination of magnesium, iron, aluminum, silicon (at a mass proportion of each from 0.01 to 0.7%) and lead (at a mass fraction of lead from 0.001 to 0.03%) in megabezemboy the ligature.

The method is based on the excitation spectrum of the sample, previously translated into oxide and mixed with carbon powder, the arc of DC in the coal electrode. The spectrum is recorded on a photographic plate quartz spectrograph medium dispersion. Analysis carried out by the method of «three standards».

1. GENERAL REQUIREMENTS

1.1. General requirements for method of analysis according to GOST 23685−79.

2. APPARATUS, MATERIALS AND REAGENTS

The quartz type spectrograph ISP-30.

Microphotometer.

Power supply arc DC (20 A, 300 V).

Analytical scale type ADV-200 GOST 24104−80*.
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* On the territory of the Russian Federation GOST 24104−2001. — Note the manufacturer’s database.

Fibroidsmiracle at the base of the vibrator of IV-19 with a set of containers and balls made of copper for grinding powders made according to technical documentation approved in the established order.

Muffle furnace, type MP-2.

Table lathe for the manufacture of carbon electrodes 16 ТО2П.

Electric tile according to GOST 14919−83.

Crucibles porcelain with GOST 9147−80, with a capacity of 15−30 cm.

Coals spectral type-3, b-3, high purity 7−3.

Electrodes: top sharpen on a lathe to a truncated cone with the diameter of the small base of 2 mm, bottom made in the form of a Cup with the size of crater 3,2x1,5 mm (drawing).

Coal powder high purity 7−4.

Photographic plates of the spectral type 2, ES.

Cup platinum according to GOST 6563−75.

Nitric acid of high purity according to GOST 11125−78*.
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* On the territory of the Russian Federation GOST 11125−84. — Note the manufacturer’s database.

Aluminum oxide anhydrous.

Beryllium hydroxide.

Acetic acid GOST 61−75.

Hydrochloric acid of high purity according to GOST 14261−77 diluted 1:1.

Chloroform.

Beryllium oxide: 400 g hydroxide of beryllium is placed in a heat-resistant glass with a capacity of 2,000 cmand 1500 cm dissolved
acetic acid. Pour about 300 cmof acetic acid and stirred periodically for 30 min with a glass rod. After the cessation of violent reaction is introduced in portions of 300 cmthe rest of the acid. The resulting mixture was boiled until the formation of crystals of acetate of beryllium and cooled. The precipitated crystals are filtered under vacuum on a Buchner funnel.

Beryllium acetate and the funnel was transferred to a beaker, which held the dissolution, add 800 cmof acetic acid, stirred and heated. Is dorstenia hydroxide of beryllium and rinsing the obtained acetate of beryllium. After cooling, the precipitated crystals filtered under vacuum and again transferred into the same beaker. Crystals of acetate of beryllium is dissolved in 1000 cmof chloroform, the solution was filtered under vacuum through a double filter of «blue ribbon». The filtrate was transferred to a flask with a glass stopper. A portion of the filtrate was placed in a quartz separating funnel (one-third of the volume of the funnel) and perform the extraction of the impurities with hydrochloric acid diluted 1:1, when the ratio of organic and aqueous phase of 5:1. The extraction is carried out seven times shaking the funnel vigorously for 3−5 min. the Organic phase portions 200 cmthree times washed with water, purified by ion-exchange method, with the same phase ratio, placed in a quartz flask with a capacity of 1000−2000 cmand evaporated to remove the chloroform.

Beryllium acetate obtained is dissolved in 500 cmof nitric acid when heated. The solution was transferred to a platinum Cup and evaporated on a hot plate to dryness. Then the Cup is placed in a muffle furnace and calcined at a temperature of 900 °C for 2 h. the Oxide of beryllium is poured into a polyethylene jar.

Silicon dioxide according to GOST 9428−73.

Iron oxide according to GOST 4173−77.

Magnesium oxide according to GOST 4526−75.

Copper grade M-0, M-1 according to GOST 859−78* (ST SEV 226−75).
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* On the territory of the Russian Federation GOST 859−2001. — Note the manufacturer’s database.

Copper oxide: copper metal dissolved in nitric acid and calcined at a temperature of 600−700 °C.

Lead oxide according to GOST 9199−77.

The mixture for dilution with a mass fraction of 10% of beryllium and 90% copper oxide and beryllium oxide of copper rubbed on fibroidsmiracle for 40−50 min. (with manual mode cooking — 90−120 min).

The developer consisting of two solutions.

Solution 1:

Solution 2:

Identical volumes 1 and 2 the solutions were poured before the manifestation, which is carried out at a temperature of 20±1 °C.

Fixer of the following composition:

It is allowed to apply a different contrast developer.

(Changed edition, Rev. N 1).

3. PREPARATION FOR ASSAY

3:1.Sample preparation

The hitch of the ligature with a mass of about 1 g is dissolved in nitric acid, evaporated to dryness on the tile and calcined in a muffle furnace at a temperature of 700−800 °C for 15−20 min the resulting mixture is mixed with carbon powder in the ratio of 2.5:1 on fibroidsmiracle for 10−15 min, in manual mode, cooking time, grinding is 20−30 min.

When the mass fraction of magnesium in the ligature more than 0.3% of the obtained oxide pre-diluted mixture for dilution 5 times, then mixed with charcoal powder.

3.2. The preparation of calibration samples

Calibration samples are prepared on the basis of oxide of copper and oxide of beryllium. The composition and method of preparation of primary calibration sample given in table.1, the working calibration samples in table.2.

Table 1

Table 2

All the main components of the calibration sample is stirred on fibroidsmiracle for 30−40 minutes, in manual mode, cooking time, grinding is 90−120 min.

Workers of the calibration samples is prepared by successive dilution (dilution is calculated according to the impurity content of the sum of the metals) of the basic calibration of the sample mixture to dilute and mix with the coal powder in a ratio of 2.5:1 on fibroidsmiracle for 30−40 min. (with manual mode cooking — 90−120 min).

The calibration samples are stored in plotnosti plastic, glass jars or buksh.

Shelf life — 1 year from date of manufacture.

4. ANALYSIS

Analyzed and calibration samples are tightly Packed into the electrodes. The electrode to analyze the sample serves as the anode. Photographing spectra is carried out on the spectrograph ISP-30 under the following conditions:

The intermediate diaphragm is chosen such that the background in the area of 300.0 nm was 0.3 to 0.4 units of blackening.

On the plate photographed at three range of samples and calibration samples.

5. PROCESSING OF THE RESULTS

5.1. Photographic plates shown in the standard condition, photometrist on microphotometer. Analytical lines of the determined elements, comparison lines and the range of determined concentrations is given in table.3.

Table 3

The results of electrophoretic spectra of the calibration samples to build calibration graphs in the coordinate , where is the logarithm of the mass fraction of the element in the calibration sample, and the difference pucherani analytical line of the designated item and line comparison, where is the arithmetic mean of the difference of pochernenija of the three spectrograms obtained for the calibration samples.

The graphs and the results of the electrophoretic spectra of the samples find the mass fraction of detectable elements.

The relative standard deviation of analysis results is 0.15.

Mass fraction of the element () in % to 1% of beryllium is calculated by the formula

,

where  — mass fraction of the element in the alloy, %;

 — mass fraction of beryllium in the alloy, %.