GOST 11739.10-90
GOST 11739.10−90 Alloys aluminium cast and wrought. Methods for determining lithium
GOST 11739.10−90
Group B59
STATE STANDARD OF THE USSR
ALLOYS ALUMINIUM CAST AND WROUGHT
Method for the determination of lithium
Aluminium casting and wrought alloys.
Method for determination of lithium
AXTU 1709
Valid from 01.07.91
before 01.07.96*
_______________________________
* Expiration removed
Protocol 5−94 N Interstate Council
for standardization, Metrology and certification
(IUS N 11/12, 1994). — Note the manufacturer’s database.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of aviation industry of the USSR
DEVELOPERS
V. G. Davydov, doctor of engineering. Sciences; V. A. Moshkin, PhD. tech. Sciences; G. I. Friedman, PhD. tech. Sciences; M. N. Gorlova, PhD. chem. Sciences; V. A. Osipova, Cand. chem. Sciences
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee on management of quality and standards from
3. The frequency of inspection — 5 years
4. REPLACE GOST 11739.10−78
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced |
Paragraph number section |
| GOST 3118−77 |
3 |
| GOST 4038−79 |
3 |
| GOST 4204−77 |
3 |
| GOST 4461−77 |
3 |
| GOST 5457−75 |
3 |
| GOST 10484−78 |
3 |
| GOST 10929−76 |
3 |
| GOST 11069−74 |
3 |
| GOST 25086−87 |
1.1 |
| THAT 6−09−3728−74 |
3 |
This standard sets flame photometric method for the determination of lithium in a mass proportion of from 0.05 to 3.0%.
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 25086 with the Supplement.
1.1.1. For the results analysis be the arithmetic mean of results of two parallel measurements.
2. THE ESSENCE OF THE METHOD
The method is based on dissolving the sample in hydrochloric acid and subsequent measurement of the radiation intensity of the lithium at a wavelength of 670,8 nm in the flame acetylene-air.
3. APPARATUS, REAGENTS AND SOLUTIONS
The fiery photometer or spectrophotometer atomic absorption operating in the mode of emission.
Oven muffle.
Drying oven with thermostat.
Acetylene according to GOST 5457, cleaned with sulfuric acid.
Sulfuric acid according to GOST 4204, density 1.84 g/cm.
Nitric acid according to GOST 4461, density 1,35−1,40 g/cm.
Hydrochloric acid according to GOST 3118, density of 1.19 g/cm, mortar 1:1 and 1:99.
Hydrofluoric acid according to GOST 10484.
Hydrogen peroxide according to GOST 10929.
Lithium carbonate on the other 6−09−3728.
Standard solution of lithium: 5,32 g of lithium carbonate, previously dried at a temperature of 100−105 °C to constant weight, is placed in a conical flask with a capacity of 250 cm, add 20 cm
of a hydrochloric acid solution of 1:1 and dissolved by heating. After dissolution, the cooled solution is transferred into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water and mix.
1 cmstandard solution contains 0.001 g of lithium.
Nickel chloride according to GOST 4038, a solution of 2 g/DM.
Aluminium GOST 11069* brand А999.
_______________
* On the territory of the Russian Federation GOST 11069−2001. — Note the manufacturer’s database.
A solution of aluminum 50 g/DM: 25 g of aluminum was placed in a conical flask with a capacity of 600 cm
, add 50 cm
of water, then small portions of 400 cm
of a hydrochloric acid solution (1:1) and dissolved by heating, adding 1 cm
of solution of chloride Nickel. The solution was cooled to room temperature, transferred to a volumetric flask with a capacity of 500 cm
, made up to the mark with water and mix.
4. ANALYSIS
4.1. A portion of the sample weighing 1 g is placed in a conical flask with a capacity of 250 cm, pour approximately 10 cm
of water, then small portions of 20 cm
of a hydrochloric acid solution (1:1) and heated moderately until the end of the dissolution. Add 3−5 drops of hydrogen peroxide and boiled for 3 min. the Solution was cooled to room temperature, transferred to a volumetric flask with a capacity of 100 cm
, made up to the mark with water and mix.
4.2. When the mass fraction of silicon in excess of 1% after completion of dissolution according to claim 4.1 solution is filtered through a filter medium density (white ribbon) in a volumetric flask with a capacity of 100 cm. The filter cake was washed 3−4 times with hot hydrochloric acid (1:99) in portions of 10 cm
(primary filtrate).
The filter with precipitate was placed in a platinum crucible, dried, incinerated, preventing ignition, and calcined at 500−600 °C for 3 min. After cooling the content of crucible add four drops of sulphuric acid, 5 cmhydrofluoric acid and nitric acid drop by drop until a clear solution. The solution was then evaporated to dryness and after cooling, the residue moistened with 2−3 cm
of water and dissolve in 2−3 cm
of hydrochloric acid (1:1) under heating.
The solution is attached to the main filtrate in a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.
4.3. Depending on the mass fraction of lithium according to table.1 select aliquot part of the solution in a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.
Table 1
| Mass fraction of lithium, % |
The volume aliquote part of the solution, cm |
The weight of the portion of the sample in aliquote part of the solution, g |
| From 0.05 to 0.5 incl. |
50 |
0,50 |
| SV. Of 0.5 «to 3.0 « |
10 |
0,05 |
4.4. The solution in the reference experiment is prepared according to PP.4.1, 4.2, 4.3.
4.5. Construction of calibration graphs
4.5.1. When the mass fraction of lithium from 0.05 to 0.5% in seven volumetric flasks with a capacity of 100 cmplaced at 10 cm
of a solution of aluminum. Six of them measure 0,25; 0,5; 1,0; 1,5; 2,0; 2,5 cm
standard solution of lithium, which corresponds to 0,00025; 0,0005; 0,001; 0,0015; 0,002; 0,0025 g of lithium.
4.5.2. When the mass fraction of lithium in excess of 0.5 to 3.0% in the six volumetric flasks with a capacity of 100 cmplaced at 1 cm
of a solution of aluminium, in five of them measure 0,25; 0,5; 1,0; 2,0; 3,0 cm
standard solution of lithium, which corresponds to 0,00025; 0,0005; 0,001; 0,002; 0,003 g of lithium.
4.5.3. The solutions in flasks in PP.4.5.1 and 4.5.2 topped up to the mark with water and mix.
Solutions that do not contain lithium, are the solutions in the reference experiment when constructing the calibration graphs.
4.6. Solutions of the sample solution in the reference experiment and the solutions for constructing the calibration curve is sprayed into the flame of acetylene-air and measure the emission intensity of lithium at a wavelength of 670,8 nm.
According to the obtained values of radiation intensity and corresponding mass concentrations of lithium build a calibration curve.
Mass concentration of lithium in the sample solution and the solution of control and experience determined by the calibration schedule.
5. PROCESSING OF THE RESULTS
5.1. Mass fraction of lithium (a) percentage calculated by the formula
where is mass concentration of lithium in the sample solution found by the calibration schedule, g/cm
;
— mass concentration of lithium in solution in the reference experiment, was found in the calibration schedule, g/cm
;
— the volume of the sample solution, cm
;
— the weight of the portion in the corresponding aliquote part of the sample solution, g
.
5.2. Discrepancies in the results must not exceed the values given in table.2.
Table 2
| Mass fraction of lithium, % |
The absolute allowable difference, % | |
| results of parallel measurements |
the results of the analysis | |
| From 0.050 to 0.100 incl. |
0,004 |
0,005 |
| SV. Of 0.10 «to 0.25 « |
0,01 |
0,02 |
| «0,25» 0,50 « |
0,02 |
0,03 |
| «0,50» 1,00 « |
0,03 |
0,04 |
| «Of 1.00» to 3.00 « |
0,05 |
0,06 |
