GOST 6689.20-92
GOST 6689.20−92 Nickel, alloys Nickel and copper-Nickel. Methods for determination of lead
GOST 6689.20−92
Group B59
STATE STANDARD OF THE USSR
NICKEL, ALLOYS NICKEL AND COPPER-NICKEL
Methods for determination of lead
Nickel, nickel and copper-nickel alloys. Methods for the determination of lead
AXTU 1709
Date of introduction 1993−01−01
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of metallurgy of the USSR
DEVELOPERS
V. N. Fedorov, Y. M. Leybov, Boris N. Krasnov, A. N. Bulanova, L. V. Morea, A. I. Vorobyov
2. APPROVED AND promulgated by the Decree of Committee of standardization and Metrology of the USSR from
3. REPLACE GOST 6689.20−80
4. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced |
The number of the paragraph, subparagraph, section |
| GOST 8.315−91 |
2.4.3; 3.4.3; 4.4.3; 5.4.3 |
| GOST 492−73 |
Chapeau |
| GOST 596−89 |
2.2 |
| GOST 2062−77 |
4.2; 5.2 |
| GOST 3117−78 |
2.2 |
| GOST 3118−77 |
4.2; 5.2 |
| GOST 3760−79 |
4.2; 5.2 |
| GOST 3778−77 |
2.2; 4.2; 5.2 |
| GOST 4109−78* | 4.2; 5.2 |
_______________ * Probably a mistake of the original. Should read GOST 4109−79. — Note the manufacturer’s database. | |
| GOST 4147−74 |
4.2; 5.2 |
| GOST 4204−77 |
2.2 |
| GOST 4207−75 |
2.2 |
| GOST 4233−77 |
2.2 |
| GOST 4461−77 |
2.2; 3.2; 4.2; 5.2 |
| GOST 4658−73 |
4.2 |
| GOST 6552−80 |
4.2 |
| GOST 6563−75 |
3.2 |
| GOST 6689.1−92 |
Sec. 1 |
| GOST 9293−74 |
4.2 |
| GOST 10484−78 |
5.2 |
| GOST 10652−73 |
2.2 |
| GOST 10929−76 |
5.2 |
| GOST 18300−87 |
2.2, 3.2 |
| GOST 19241−80 |
Chapeau |
| GOST 25086−87 |
Section.1; 2.4.3; 3.4.3; 4.4.3; 5.4.3 |
This standard establishes titrimetric chelatometric and electrogravimetry methods for determination of lead (with a mass fraction of lead from 1.0 to 2.5%), a polarographic method for the determination of lead (with a mass fraction of lead from 0.002 to 0.1%) and atomic absorption method for the determination of lead (with a mass fraction of lead from 0.002 to 0.02%; 0.02 to 0.1%, and from 1 to 2.5%) in Nickel, Nickel and copper-Nickel alloys according to GOST 492* and GOST 19241.
________________
* On the territory of the Russian Federation GOST 492−2006. — Note the manufacturer’s database.
1. GENERAL REQUIREMENTS
General requirements for methods of analysis GOST 25086 with the addition of sec. 1 GOST 6689.1.
2. TITRIMETRIC CHELATOMETRIC METHOD FOR THE DETERMINATION OF LEAD
2.1. The essence of the method
The method is based on complexometric titration of lead at pH of 5.5−6.0 in the presence kylinalove orange as indicator after the separation of lead sulfate and dissolving the latter in a solution of acetate of ammonium.
2.2. Reagents and solutions
Nitric acid according to GOST 4461, diluted 1:1.
Sulfuric acid according to GOST 4204, diluted 1:1 and 1:50.
Ammonium acetate according to GOST 3117, a solution of 250 g/DM.
Potassium ferrocyanide according to GOST 4207, a solution of 30 g/DM.
Rectified ethyl alcohol according to GOST 18300.
Lead metal stamps S0 GOST 3778*.
______________
* On the territory of the Russian Federation GOST 3778−98, here and hereafter. — Note the manufacturer’s database.
Selenology orange mixed with sodium chloride in a ratio of 1:100, carefully triturated.
Sodium chloride according to GOST 4233.
Sodium sulfide according to GOST 596, a solution of 20 g/DM.
Ethylenediamine-N, N, N', N'-tetraoxane acid disodium salt, 2-water (Trilon B) according to GOST 10652, solution 0,025 mol/DM:
9,305 g Trilon B dissolved in 500 cmof water when heated, transferred to a measuring flask with volume capacity of 1000 cm
and topped to the mark with water.
The installation of the mass concentration of the solution Trilon B.
A portion of lead with a mass of 0.1 g was placed in a beaker with a capacity of 300 cm, add 15 cm
of nitric acid, cover with watch glass, glass or plastic plate and dissolved by heating. After the dissolution of a glass or plate and the side of the Cup and rinse with water, add 40 cm
of sulphuric acid (1:1), evaporated until copious white smoke of sulfuric acid, cooled, rinse the walls of the glass with water and again evaporated until white smoke of sulfuric acid. The solution was cooled, poured 150 cm
of water, heated to boiling, again cooled, added 40 cm
of ethanol and left for 4 h. Further analysis are as indicated in claim 2.3.
Mass concentration of the solution Trilon B, expressed in grams of lead per 1 cmof a solution, calculated by the formula
where — volume of solution Trilon B, spent on titration, sm
.
2.3. Analysis
A sample weighing 1 g is placed in a beaker with a capacity of 300 cm, add 15 cm
of nitric acid, cover with watch glass, glass or plastic plate and dissolved by heating. After dissolution of the alloy is rinsed glass or plate and the side of the Cup with water, add 40 cm
of sulphuric acid (1:1) and evaporated until copious white smoke of sulfuric acid. The solution was cooled, the side of the Cup then rinsed with water and again evaporated until a white smoke of sulfuric acid. The solution was cooled, poured 150 cm
of water, heated to dissolve the salts, and cooled. Add 40 cm
of ethyl alcohol and allowed to stand for 4 h.
The separated precipitate of lead sulphate filtered off on a tight filter, a glass and the precipitate washed with sulphuric acid (1:50) to remove copper ions in the washing water (test with potassium ferrocyanide), and then 2−3 times with water. The filter with precipitate was placed in a beaker, which was carried out sedimentation, flow 30 cmof a solution of acetate of ammonium and carefully crushed the filter with a glass rod. Beaker cover watch glass, and heated and maintained at a temperature close to the boiling point for 20 min. Then diluted with water to 150 cm
and heated for 10 min.
The solution was cooled, added at the tip of a spatula mix kylinalove orange with sodium chloride and slowly titrated with a solution of Trilon B to a transition of a purple color to yellow
.
2.4. Processing of the results
2.4.1. Mass fraction of lead (a) percentage calculated by the formula
where — volume of solution Trilon B, used for titration, cm
;
— mass concentration of the solution Trilon B on lead, g/cm
;
— the weight of the portion,
2.4.2. Discrepancies in the results of three parallel measurements (rate of convergence) and the results of the two tests
(index of reproducibility) shall not exceed the values of permissible differences given in table.1.
Table 1
| Mass fraction of lead, % | The allowable divergence, % | |
| From 0.002 to 0.005 incl. |
0,0008 | 0,001 |
| SV. 0,005 «0,010 « |
0,001 | 0,001 |
| «Of 0.010» to 0.025 « |
0,002 | 0,003 |
| «Of 0.025» to 0.05 « |
0,004 | 0,006 |
| «0,05» 0,1 « |
0,005 | 0,007 |
| From 1.0 to 2.5 « |
0,08 | 0,1 |
2.4.3. Control of accuracy of analysis results is carried out according to State standard samples (GSO) or industry standard sample (CCA), or by standard samples of the enterprise (SOP) of copper-Nickel alloys, approved under GOST 8.315*, or by a method of additives, or a comparison of the results obtained electrogravitational or atomic absorption methods, in accordance with GOST 25086.
________________
* On the territory of the Russian Federation GOST 8.315−97, here and hereafter. — Note the manufacturer’s database.
3. ELECTROGRAVIMETRY METHOD FOR THE DETERMINATION OF LEAD
3.1. The essence of the method
The method is based on the release of lead electrolytically in the form of its dioxide at the anode and weighing the separated precipitate of dioxide of lead.
3.2. Equipment, reagents, solutions
Electrolysis installation DC.
Platinum mesh electrodes according to GOST 6563.
Nitric acid according to GOST 4461, diluted 1:1.
The sulfamic acid.
The technical rectified ethyl alcohol according to GOST 18300.
3.3. Analysis
A sample weighing 0.5 g were placed in a glass with a capacity of 250 cm, add 15 cm
of nitric acid, cover with watch glass, glass or plastic plate and dissolved by heating. After dissolution of the alloy watch glass or plate and the side of the Cup then rinsed with water, the solution heated to boiling, add 0.5 g of sulfamic acid, dilute with water to 150 cm
.
In the weighted solution is immersed an anode and a cathode and conducting electrolysis with a current of 1.5−2 And while stirring the solution. The glass electrolyte must be covered by the two halves of the hour glass or plastic plate with holes for electrodes and stirrer.
After 30 min from the start of the electrolysis is removed or the glass plate, rinsed with water, and continue the electrolysis for 15 minutes, If after that svezhemorozhenoj in the solution part of the anode is not allocated sediment, the electrolysis is complete. Without turning off the current, quickly remove the beaker with the electrolyte and washed electrodes, substituting in turn the three cups with distilled water. Current is turned off, remove the anode and the precipitate of lead dioxide, immersed in a glass with 200 cmof ethyl alcohol, and dried it at a temperature of 160−170 °C to constant weight, cooled and weighed. One serving of alcohol may be used for washing no more than 20 electrodes.
3.4. Processing of the results
3.4.1. Mass fraction of lead (a) percentage calculated by the formula
where is the mass of the anode from the separated precipitate of dioxide of lead, g;
— mass of anode, g;
0,8661 — the conversion factor of lead dioxide on a lead; — the weight of the portion,
3.4.2. Discrepancies in the results of three parallel measurements (rate of convergence) and the results of the two tests
(index of reproducibility) shall not exceed the values of permissible differences given in the table.
3.4.3. Control of accuracy of analysis results is carried out according to State standard samples (GSO) or industry standard sample (CCA), or by standard samples of the enterprise (SOP) of copper-Nickel alloys, approved under GOST 8.315, or by additives, or by comparing the results obtained with titrimetric or atomic absorption methods, in accordance with GOST 25086.
3.4.4. Electrogravimetry method is used with differences in the assessment of the quality of copper-Nickel alloys.
4. POLAROGRAPHIC METHOD FOR THE DETERMINATION OF LEAD
4.1. The essence of the method
The method is based on the polarographic determination of lead on a background of phosphoric acid at a potential of minus 0.47 In peak relative to a saturated calomel electrode after prior separation of lead by coprecipitation with iron hydroxide.
4.2. Apparatus, reagents and solutions
Polarograph PPT-I with all facilities. Allowed the use of data handling other brands.
Hydrochloric acid according to GOST 3118 and diluted 1:1 and 1:3.
Nitric acid according to GOST 4461, diluted 1:1 and 1:3.
The acid chloride.
Orthophosphoric acid according to GOST 6552 and diluted 1:3, and the solution is 1 mol/DM.
Bromatologia acid according to GOST 2062.
Bromine according to GOST 4109.
The mixture for dissolution, fresh: 9 parts bromatological acid mixed with one part of bromine.
Ammonia water according to GOST 3760 and diluted 1:100.
Iron chloride according to GOST 4147, a solution of 15 g/lin hydrochloric acid (1:3).
Lead according to GOST 3778 with a mass fraction of lead of at least 99.9%.
Standard solutions of lead
Solution a: 1 g of lead is dissolved by heating in 30 cmof nitric acid (1:1), and remove the oxides of nitrogen by boiling, cool, pour 50 cm
of water, transfer the solution into a measuring flask with volume capacity of 1000 cm
and topped to the mark with water.
1 cmof the solution contains 0.001 g of lead.
Solution B: 10 cmsolution And transferred to a volumetric flask with a capacity of 100 cm
and then filled to the mark with water.
1 cmof a solution contains 0.0001 g of lead.
Mercury r0 according to GOST 4658, dehydrated.
Nitrogen gas according to GOST 92
93.
4.3. Analysis
4.3.1. For alloys with a mass fraction of tin in excess of 0.05%
A sample of alloy weighing 1 g is placed in a beaker with a capacity of 250 cmand gently dissolved in 20 cm
of the mixture for dissolution. In case of incomplete dissolution gently added to a glass of bromine dropwise. Poured to a solution of 10 cm
of perchloric acid and evaporated to clarification of the solution and the appearance of dense white smoke. The residue is cooled, diluted with water to 100 cm
, add 3−5 cm
of a solution of ferric chloride (at a mass fraction of iron in the alloy is less than 0.5%) and ammonia to form a dark blue complex of copper and Nickel and, moreover, another 5 cm
of ammonia in excess, incubated at 60−70 °C for 30 min and filtered off the precipitate on a filter of medium density. The glass and the filter cake was washed 3−4 times with hot ammonia solution (1:100) and four times with warm water. Wash the precipitate from the filter with water glass, which conducted the deposition, the precipitate was dissolved in 10 cm
of hot hydrochloric acid (1:1) and washed the filter several times with hot water. The resulting solution was diluted to a 125−150 cm
of water and repeating reprecipitation. Then the filter cake is dissolved in 5 cm
of perchloric acid, dilute with water to 25 cm
and evaporated until a white thick smoke. Cool the solution, add 14 cm
of phosphoric acid (1:3), transfer the solution into a volumetric flask with a capacity of 50 cm
and top up solution to the mark with water. Part of the solution is transferred into a polarographic vessel, pre-washed in 1 mol/DM
solution of phosphoric acid, the solution was degassed for 5−7 min with a nitrogen flow and polarographic solution in the range from minus 0.25 to minus of 0.70 In a relatively saturated calomel electrode. Simultaneously with the determination of lead conduct control experience with all reagents and samples with the addition of a standard solution of lead equal in weight to the estimated lead content in the sample analyzed
sample.
4.3.2. For alloys with a mass fraction of silicon in excess of 0.05%
A sample of alloy weighing 1 g is placed in a platinum Cup and dissolved in 10 cmof nitric acid (1:1) and 1 cm
hydrofluoric acid. Add 10 cm
of perchloric acid and evaporated until the appearance of dense white smoke of perchloric acid. The residue is cooled, dissolved the residue in water and transferred to a beaker with a capacity of 250 cm
, top up with water to a volume of 150 cm
, add 3 cm
of a solution of ferric chloride and then act as described in section
4.3.3. For alloys with a mass fraction of tin and silicon is less than 0.05%
A sample of alloy weighing 1 g is placed in a beaker with a capacity of 250 cm, and dissolved in 10 cm
of nitric acid (1:1). Remove the oxides of nitrogen by boiling, dilute the solution with water to 125−150 cm
, add 3−5 cm
of a solution of ferric chloride and then act as described in section
4.4. Processing of the results
4.4.1. Mass fraction of lead (a) percentage calculated by the formula
where is the peak height of lead for sample solution, ml;
the peak height of lead solution in the reference experiment, mm.
the peak height of lead for a sample solution with a standard additive, mm;
— the concentration of a standard solution of lead, g/cm
;
— the volume of the additive standard solution, cm
;
— the weight of the portion,
G.
4.4.2. Discrepancies in the results of three parallel measurements (rate of convergence) and the results of the two tests
(index of reproducibility) shall not exceed the values of permissible differences given in the table.
4.4.3. Control of accuracy of analysis results is carried out according to State standard samples (GSO) or industry standard sample (CCA), or by standard samples of the enterprise (SOP) of Nickel, Nickel and copper-Nickel alloys, approved under GOST 8.315, or by a method of additives, or a comparison of the results obtained by atomic absorption method, in accordance with GOST 25086.
5. ATOMIC ABSORPTION METHOD FOR DETERMINATION OF LEAD
5.1. The essence of the method
The method is based on measuring the absorption of light by atoms of lead, formed by the introduction of the analyzed solution in the flame acetylene-air. When the mass fraction of lead from 0.002 to 0.02% conduct pre-release of lead by coprecipitation with iron hydroxide.
5.2. Apparatus, reagents and solutions
Atomic absorption spectrometer with a radiation source for lead.
Nitric acid according to GOST 4461 and diluted 1:1.
Hydrochloric acid according to GOST 3118 and diluted 1:1 solutions of 1 and 2 mol/DM.
The mixture of acids to dissolve 1: mix one volume of nitric acid with three volumes of hydrochloric acid.
Hydrofluoric acid according to GOST 10484.
The acid chloride.
Bromatologia acid according to GOST 2062.
Bromine according to GOST 4109.
The mixture of acids to dissolve 2, fresh: 9 parts bromatological acid mixed with one part of bromine.
Ammonia water according to GOST 3760 and diluted 1:19.
Hydrogen peroxide according to GOST 10929.
Iron chloride according to GOST 4147, a solution of 15 g/lin hydrochloric acid (1:3).
Lead according to GOST 3778.
Standard solutions of lead.
Solution a: 0.1 g of lead is dissolved by heating in 10 cmof nitric acid (1:1). The solution was transferred to a volumetric flask with a capacity of 100 cm
and top up with water to the mark.
1 cmof the solution contains 0.001 g of lead.
Solution B: 10 cmsolution And transferred to a volumetric flask with a capacity of 100 cm
and top up with water to the mark.
1 cmof a solution contains 0.0001 g of lead-acid batterie
.
5.3. Analysis
5.3.1. The definition of a mass fraction of lead from 0.002 to 0.02%
5.3.1.1. For alloys with a mass fraction of tin and silicon up to 0.05%
A sample of alloy weighing 2 g were placed in a glass with a capacity of 250 cmand dissolved by heating in 20 cm
of nitric acid (1:1). Nitrogen oxides are removed by boiling and the solution diluted with water to a volume of 150 cm
. Add 5 cm
of solution of chloric iron (alloys containing iron as an alloying component do not add the solution of ferric chloride), the solution is heated to a temperature of 80−90 °C and ammonia is added to complete the transition of copper and Nickel into soluble ammonia complexes. Solution and the precipitate of hydroxides is allowed to stand for approximately 10 minutes at a temperature of 60 °C and then filtered on a medium density filter and washed with hot ammonia solution (1:19) for the removal of copper and Nickel, and then three times with hot water.
The deployed filter washed with hot water into a glass, which conducted the deposition. The filter is washed with 10 cmof hot hydrochloric acid (1:1) and then with water. The washed filter is discarded and the solution was evaporated to a volume of 5 cm
. The solution was cooled, added to 10 cm
of water, transferred to a volumetric flask with a capacity of 25 cm
and top up with water to the mark.
Measure the atomic absorption of lead in the flame of acetylene-air at a wavelength is 283.3 nm parallel to the calibration solutions
I.
5.3.1.2. For alloys with a mass fraction of tin in excess of 0.05%
A sample of alloy weighing 2 g were placed in a glass with a capacity of 250 cm, adding 25 cm
of the mixture for dissolution (2) and gently heated until complete dissolution. Then add 10 cm
of perchloric acid and evaporated to a volume of 5 cm
. The residue was cooled, added to 30 cm
of water and heated to dissolve the salts. The solution is diluted with water to a volume of 150 cm
, add 5 cm
of a solution of ferric chloride and then analysis is carried out as specified in clause
.
5.3.1.3. For alloys with a mass fraction of silicon in excess of 0.05%
A portion of the alloy with a mass of 2 g is placed in a platinum Cup and dissolved by heating in 20 cmof nitric acid (1:1) and 2 cm
hydrofluoric acid. After cooling, add 10 cm
of perchloric acid and heated until the appearance of dense white fumes. The residue was cooled, added to 30 cm
of water and heated to dissolve the salts. The solution was transferred to a beaker with a capacity of 250 cm
, is diluted with water to a volume of 150 cm
, add 5 cm
of a solution of ferric chloride and then analysis is carried out as specified in clause
.
5.3.2. The definition of a mass fraction of lead from 0.02 to 0.1% and from 1% to 2%
A sample of alloy weighing 1 g is taken to determine the mass fraction of lead from 0.02 to 0.1% by weight of 0.1 g to determine the mass fraction of lead from 1 to 2%.
5.3.2.1. For alloys with a mass fraction of tin and silicon up to 0.05%
A portion of the alloy is dissolved by heating in 10 cmof nitric acid (1:1). The solution was transferred to a volumetric flask with a capacity of 100 cm
and top up with water to the mark.
Measure the atomic absorption of lead in the flame of acetylene-air at a wavelength is 283.3 nm parallel to the calibration solutions.
5.3.2.2. For alloys with a mass fraction of tin in excess of 0.05%
A portion of the alloy is dissolved by heating in 10 cmof the mixture of acids to dissolve (1). The solution was transferred to a volumetric flask with a capacity of 100 cm
and topped to the mark of 1 mol/DM
hydrochloric acid solution. Measure the atomic absorption of lead, as specified in clause
5.3.2.3. For alloys with a mass fraction of silicon in excess of 0.05%
A portion of the alloy placed in a platinum Cup and dissolved by heating in 10 cmof nitric acid (1:1) and 2 cm
hydrofluoric acid. After dilution pour 10 cm
of nitric acid (1:1) and the solution was evaporated to dryness. Then add 10 cm
of nitric acid (1:1) and the solution was evaporated to dryness. The residue is dissolved in 10 cm
of nitric acid (1:1), the solution transferred to a volumetric flask with a capacity of 100 cm
and top up with water to the mark. Measure the atomic absorption of lead, as specified in clause
5.3.3. Construction of calibration curve
In seven of the eight volumetric flasks with a capacity of 100 cmis placed 1,0; 3,0 and 5,0 cm
of standard lead solution B; 1,0; 1,5; 2,0 and 2,5 cm
And a standard solution of lead, which corresponds to 0,1; 0,3; 0,5; 1,0; 1,5; 3,0 and 2.5 mg of lead. All flasks is poured 10 cm
of 2 mol/DM
hydrochloric acid solution and add water to the mark.
Measure the atomic absorption of lead, as specified in clause
5.4. Processing of the results
5.4.1. Mass fraction of lead (a) percentage calculated by the formula
where is the concentration of lead was found in the calibration schedule, g/cm
;
— the volume of the sample solution, cm
;
— the weight of the portion of the sample,
5.4.2. Discrepancies in the results of three parallel measurements (rate of convergence) and the results of the two tests
(index of reproducibility) shall not exceed the values of permissible differences given in the table.
5.4.3. Control of accuracy of analysis results is carried out according to State standard samples (GSO) or industry standard sample (CCA), or by standard samples of the enterprise (SOP) of Nickel, Nickel and copper-Nickel alloys, approved under GOST 8.315, by additives or by comparing the results obtained with titrimetric or gravimetric, or polarographic methods in accordance with GOST 25086.
