GOST 12645.8-82
GOST 12645.8−82 indium. Chemical-spectral method of determination of tin (with Amendments No. 1, 2)
GOST 12645.8−82
Group B59
STATE STANDARD OF THE USSR
INDIUM
Chemical-spectral method of determination of tin
Indium. Method of chemical and spectral analysis for the determination of tin
AXTU 1709
Date of introduction 1983−07−01
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
DEVELOPERS
A. P. Sychev, L. K. Larin, N. With. References:
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee for standards from 7.04.82 G. N 1459
Change No. 2 adopted by the Interstate Council for standardization, Metrology and certification
The adoption voted:
| The name of the state |
The name of the national standardization body |
| The Republic Of Azerbaijan |
Azgosstandart |
| The Republic Of Belarus |
Gosstandart Of Belarus |
| The Republic Of Kazakhstan |
Gosstandart Of The Republic Of Kazakhstan |
| The Republic Of Moldova |
Moldovastandart |
| Russian Federation |
Gosstandart Of Russia |
| Turkmenistan |
The main state inspection of Turkmenistan |
| The Republic Of Uzbekistan |
Standards |
| Ukraine |
Gosstandart Of Ukraine |
3. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced |
Section number, paragraph, sub-paragraph |
| GOST 860−75 |
Sec. 3 |
| GOST 4204−77 |
« |
| GOST 5955−75 |
« |
| GOST 6709−72 |
« |
| GOST 8422−76 |
« |
| GOST 10297−94 |
« |
| GOST 11125−84 |
« |
| GOST 12645.0−83 |
1.1; 1.2 |
| GOST 19908−90 |
Sec. 3 |
| GOST 22180−76 |
« |
| GOST 22306−77 |
1.1 |
| GOST 24147−80 |
Sec. 3 |
4. Limitation of actions taken by Protocol No. 3−93 Interstate Council for standardization, Metrology and certification (ICS 5−6-93)
5. REPRINT (January 1998) with Amendments No. 1, 2 approved in December 1987-June 1996 (IUS 3−88, 9−96)
This standard specifies the chemical-spectral method of determination of tin in India with a mass fraction of tin from 1·10to 5·10
%.
(Changed edition, Rev. N 1).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST and GOST 22306 12645.0.
1.2. Safety requirements — according to GOST 12645.0.
1.1, 1.2. (Changed edition, Rev. N 1).
1.3. (Deleted, Rev. N 1).
Sec. 2. (Deleted, Rev. N 1).
3. APPARATUS, REAGENTS AND MATERIALS
The diffraction type spectrograph DFS-8 with a grating of 600 lines/mm, first order, being the illumination system of the slit.
The generator of the arc AC of PS-39, DG-2 or IVS-28.
A constant current source providing a voltage of at least 200 V and a current not less than 20 A.
Microphotometer designed to measure pucherani spectral lines.
Spectromancer of PS-18.
Analytical scale, allows to weigh with an accuracy of 0.0002 g. more
Libra torsion bar type W, allowing you to weigh with an accuracy of not more than 0.001 g.
Boxes of organic glass.
The infrared lamp of any type with laboratory auto-transformer type CTL-250−2.
Grinding machine carbon electrodes of the type CP-35, or any other type.
Tile electric heating.
Ware and quartz glass (glasses, flasks, separating funnels, etc.) according to GOST 19908.
Mortar made of organic glass with a pestle.
Muffle furnace that allows the temperature to 500 °C.
Electrodes, carbon, high purity, 6 mm in diameter with the size of the crater in a 4x4. Contractrate coal, one end of which is sharpened to a truncated cone with ground diameter of 1.5−2.0 mm.
Indium metal brand Ин000 or Ин000у according to GOST 10297.
Tin GOST 860.
Distilled water according to GOST 6709, distilled in quartz apparatus or purified on a column of ionization.
Sulfuric acid according to GOST 4204, diluted 1:3.
Nitric acid brand OS.H. 19−4 GOST 11125.
The acid chloride.
Sodium iodide according to GOST 8422.
Benzene according to GOST 5955.
Ammonia water according to GOST 24147.
Oxalic acid according to GOST 22180.
Photographic plates «spectrographic» type NT-2SV, SFC-02, the SFC-03.
India a solution of 100 g/DM: India hitch weight 2,500 g dissolved in 12.5 cm
of nitric acid under heating, cooled and transferred to volumetric flask with a capacity of 25 cm
.
A solution of tin 1 g/DM: a portion of finely ground tin weight 0,100 g dissolved in 2 cm
of nitric acid. After dissolution of tin in the beaker was added 20 cm
water and 4,000 g of oxalic acid. The solution was transferred to a volumetric flask with a capacity of 100 cm
. The glass is washed several times with water for complete dissolution of oxalic acid. The washings decanted into the same volumetric flask and bring to mark with water.
Note. Allowed the use of devices with photovoltaic spectra and other spectral instruments, other reagents and materials, providing the accuracy that rivals regulated in this standard.
Sec. 3. (Changed edition, Rev. N 1, 2).
4. PREPARATION FOR ASSAY
4.1. References
The basis for the preparation of samples of comparison is the oxide of indium: indium metal stamps Ин000 or Ин000у dissolved by heating in nitric acid, the solution was evaporated to dryness and the dry residue is calcined first on a hotplate and then in a muffle furnace at a temperature of 400−500 °C before the termination of allocation of vapors of oxides of nitrogen (30−40 min). You should pay particular attention to the completeness of removal of nitrogen oxides, as their presence in the basis increases the background in the spectrum, which distorts the results of the analysis. The content of tin in the basis determined by the method of additives and then introduced an amendment to samples comparison.
4.2. The main sample with a mass fraction of tin of 0.03% (calculated as metal indium) is prepared nakapyvaniem 3 cmof a solution of tin in the basis (12,1 g of indium oxide). The sample is dried on the hot plate and in a muffle furnace at 300 °C, triturated in a mortar and, if necessary, analyze the chemical or atomic absorption methods, is ground in a mortar.
By diluting the primary and the newly prepared samples based get series of working samples comparison, the mass fraction of tin in which is given in the table.
g
| Sample number |
Mass fraction of tin, % |
The number of diluted sample |
The number of bases needed for the dilution |
| 1 |
5·10 |
2,000 basic sample |
10,000 |
| 2 |
1·10 |
3,000 sample N 1 |
12,000 |
| 3 |
3,3·10 |
3,500 sample N 2 |
7,000 |
| 4 |
1·10 |
1,000 sample N 1 |
9,000 |
4.1, 4.2. (Changed edition, Rev. N 1, 2).
5. ANALYSIS
5.1. Sample metallic indium with a mass of 1,000 g was placed in a beaker with a capacity of 100 cmand dissolved under the watch glass when heated in 20 cm
of sulfuric acid solution (1:3). Upon evaporation of the solution should be dropwise adding water, avoiding salt precipitation. The solution was cooled to 30−40 °C, is added for oxidation of divalent tin to tetravalent 10 cm
of perchloric acid, mix and add 20 g of sodium iodide. After complete dissolution of sodium iodide and the solution transferred to a separatory funnel and shaken for 1 min with 10 cm
of benzene. After separation, wash the throat of the funnel 1−2 cm
of benzene, to separate the inorganic phase and the organic through the throat of the funnel is poured into a quartz crucible with a capacity of 50 cm
. The funnel is washed with benzene, draining it into the same crucible. There also add 1 cm
of a solution of India and placed under a heat lamp for distilling off the benzene at 50−60 °C for 30−40 min in a box made of organic glass.
Then tin hydroxide Coosada with India is added to the solution of nitrate India ammonia dropwise until a strong odor (20 drops), washing the walls of the crucible and thoroughly stirring the resulting slurry quartz wand. The resulting hydroxide dried under a lamp and then calcined in a muffle furnace at 350 to 400 °C. After calcination, the indium oxide crushed quartz with the pestle to a fine grist, and transmitted to a spectrographic analysis. Enrichment of lead from the two batches. At the same time conducting a test experience to verify the purity of reagents used. To do this in a glass with a capacity of 100 cmis placed 0.1 g of metallic indium with a mass fraction of tin is less than 1·10
%. Dissolve it under the watch glass when heated in 20 cm
of sulfuric acid solution (1:3) and then do the same as in the enrichment test.
(Changed edition, Rev. N
1).
5.2. Samples of comparison and the resulting concentrate for 45 mg is placed in the recess a carbon electrode (anode) with a diameter and a depth of 4 mm and burn in the arc of DC power 15 A for 3 min (to burnout). The spectra photographed using a diffraction spectrograph DFS-8 in the first order on photos types SFC-02, the SFC-03, NT-2SV. The width of the slit of a spectrograph 0.020 mm, distance between electrodes of 2.5 to 3.0 mm shall be maintained constant throughout the exposure.
On a photographic plate samples comparison photographed three times, each resulting concentrate twice.
(Changed edition, Rev. N 2).
6. PROCESSING OF THE RESULTS
6.1. In the spectrogram, using microphotometry measure the blackening of a line the tin with a wavelength 283,99 nm and the surrounding background.
The calibration graphs are built in coordinates 
— blackening line of tin and background;
— blackening of the background to the right of the line);
— mass fraction of tin in the samples comparison, %. Darkening of the tin lines and the background should be in the region of normal pochernenija.
According to the calibration schedule find the mass fraction of tin in concentrate of the sample and control experience.
Mass fraction of tin in India () in percent is calculated by the formula
where — mass fraction of tin in concentrate samples was found in the calibration schedule, %;
— mass fraction of tin in a control experiment, was found in the calibration schedule, %;
the weight India taken for analysis, mg.
100 — weight of the obtained concentrate, mg.
The reproducibility of the analysis of the same samples characterized by the relative standard deviation is 0.13. Repeatability of results of parallel measurements is characterized by the relative standard deviation is 0.11.
For the results analysis be the arithmetic mean of results of four parallel measurements obtained on the same photographic plate.
(Changed edition, Rev. N 1, 2).
6.2. The difference between the highest and lowest of the four results of parallel measurements with a confidence probability of 0.95 does not exceed the value of permissible differences
calculated by the formula
— the average of four matched results of parallel measurements.
The difference between the smaller and larger of the two results of analysis with confidence probability of 0.95 does not exceed the value of permissible differences
calculated by the formula
— the average of the two matched analyses.
(Changed edition, Rev. N 1
