GOST 26473.9-85
GOST 26473.9−85 Alloys and alloys based on vanadium. Method for the determination of phosphorus (Change No. 1)
GOST 26473.9−85
Group B59
STATE STANDARD OF THE USSR
ALLOYS AND MASTER ALLOYS BASED ON VANADIUM
Method of determination of phosphorus
Vanadium base alloys and alloying elements. Method for determination of phosphorus
AXTU 1709
Valid from 01.07.86
to 01.07.91*
_______________________________
* Expiration removed
by the decree of Gosstandart of the USSR from
(IUS N 8, 1991). — Note the manufacturer’s database.
DEVELOPED by the Ministry of nonferrous metallurgy of the USSR
PERFORMERS
Yu. A. Karpov, E. G. Nembrini, V. G., Miscreants, V. V. Nedler, V. M. Mikhailov, L. G. Agapova, G. N. Andrianov, A. V. Antonov, V. D. Dozen, M. A. Desyatkova, T. I. Kirillova, L. I. Kirsanov, I. E. Korepin, V. A. Orlova, N. Rasnitsyn, N. Suvorova, N. L. Tomasev, M. W. Schmidt, L. N. Filimonov
INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
Member Of The Board Of A. P. Snurnikov
APPROVED AND put INTO EFFECT by Decision of the USSR State Committee on standards of 25 March 1985 N 752
The Change N 1, approved and put into effect by the Decree of the USSR State Committee on management of quality and standards from
Change No. 1 made by the manufacturer of the database in the text IUS N 2, 1990
This standard specifies the extraction-photometric method for the determination of phosphorus (from 5·10to 5·10
%) in alloys and master alloys based on vanadium, the contents of related components which are shown in table.1.
Table 1
| The accompanying component |
Mass fraction, %, not more |
| Aluminium |
50 |
| Tungsten |
8 |
| Iron |
5 |
| Silicon |
1 |
| Manganese |
2,5 |
| Molybdenum |
25 |
| Niobium |
25 |
| Titan |
25 |
| Chrome |
40 |
| Cubic Zirconia |
3 |
The method is based on the formation of unreduced forms of the molybdophosphoric heteroalicyclic, extraction of the obtained complex with a mixture of 1-butanol with chloroform, the restoration of the complex in the organic phase with tin dichloride and fotomaterialy coloring extract.
1. GENERAL REQUIREMENTS
1.1. General requirements for methods of analysis GOST 26473.0−85.
2. APPARATUS, REAGENTS AND SOLUTIONS
Type photoelectrocolorimeter FEK-56.
Analytical scale.
Libra technical.
Tile electric.
Bath water.
Sand timer for 2 minutes, or stopwatch.
Separating funnel with a capacity of 100 cm.
Funnels, glass, conical with a diameter of 30 mm.
Volumetric flasks with a capacity of 25 and 50 cm.
Pipettes with a capacity of 1 and 5 cmwith divisions.
Pipettes with a capacity of 5 and 10 cmwith no divisions.
Microburette with a capacity of 5 cmwith a scale division of 0.02 cm
.
Measuring beakers with a capacity of 25 and 100 cm.
Crucibles of glassy carbon brand SU-2000 with a capacity of 50 cm.
Watch-glasses with a diameter of 40 mm.
The filter paper obestochennye «red ribbon» with a diameter of 70 mm.
Hydrochloric acid according to GOST 14261−77.
Nitric acid according to GOST 11125−84 and diluted 1:1.
Hydrofluoric acid according to GOST 10484−78.
Sodium molybdate according to GOST 10931−74, solution concentration of 0.4 mol/DM.
Tin dichloride 2-water, a solution of concentration 100 g/lin glycerol.
Glycerin according to GOST 6259−75.
Potassium permanganate according to GOST 20490−75, solution concentration 100 g/DM.
The technical rectified ethyl alcohol GOST 18300−87.
The 1-butanol according to GOST 6006−78.
Chloroform technical according to GOST 20015−74*.
______________
* On the territory of the Russian Federation GOST 20015−88. — Note the manufacturer’s database.
Mixture for extraction: 30 cmof 1-butanol are mixed with 70 cm
of chloroform.
Potassium phosphate according to GOST odnosemjannyj 4198−75.
A standard solution of phosphorus (V) (spare) containing 0.1 mg/cmof phosphorus: 0,430 g of single potassium phosphate is dissolved in water, transferred to a volumetric flask with a capacity of 1 DM
, adjusted to the mark with water.
A standard solution of phosphorus (V) (work) containing 0.01 mg/cm(10 µ g/cm
) phosphorus (V) prepared by diluting a backup solution with water in 10 times a day use.
(Changed edition, Rev. N 1).
3. PREPARATION FOR ASSAY
Weighed test portion weigh about 0,5 g (with a mass fraction of phosphorus from 5·10to 1·10
%) or 0.1 g (for the mass concentration of phosphorus is from 1·10
to 5·10
%) placed in a glassy carbon crucible and dissolved with gentle heating in 10 cm
of nitric acid, diluted 1:1, 3 cm
hydrofluoric acid (the dissolution of master alloys containing titanium, chromium, niobium, tungsten and zirconium) with 3 drops of a solution of potassium permanganate. The resulting solution is evaporated in a water bath to dryness. The residue is dissolved under heating in a mixture of 7 cm
of concentrated hydrochloric acid and 5 cm
of ethyl alcohol, a Cup covered with watch glass. The solution is heated to obtain a bright blue color (in the presence of a chromium solution color bright green), transferred to a volumetric flask with a capacity of 50 cm
, flow 15 cm
of concentrated hydrochloric acid, adjusted to the mark with water (stock solution), which is also used (if necessary) for determination of arsenic GOST 26473.7−85.
4. ANALYSIS
4.1. In a separating funnel with a capacity of 100 cmpipetted aliquot part of the solution was 10 cm
containing 0.5−10 µg of phosphorus, pour 2.5 cm
of concentrated hydrochloric acid, 10 cm
of a solution of molybdate of sodium and 20 cm
of the mixture for extraction. Molybdophosphate extracted by shaking the solution for 2 min.
The organic phase (lower layer) containing molybdophosphate, filtered through a dry paper filter into a dry volumetric flask with a capacity of 25 cm, the volume was adjusted to the mark with the mixture for extraction, add 1 drop of a solution of tin dichloride was mixed thoroughly. Measure the optical density of the extract on the photoelectrocolorimeter using a filter with maximum transmittance at a wavelength of ~630 nm and a dry cuvette with the thickness of the light absorbing layer 50 mm relative to the solution in the reference experiment.
Control the experience on the phosphorus content in the reagents is carried out through all stages of the analysis along with an analysis of a series of samples. The value of the optical density of the solution in the reference experiment, measured relative to the mixture for extraction, should not exceed 0.05, otherwise change the reagents.
A lot of find phosphorus for the calibration schedule.
4.2. Construction of calibration curve
In a separating funnel with a capacity of 100 cmpoured with a pipette of 10 cm
of the solution in the reference experiment, injected from microburette of 0.05, 0.1, 0.5 and 1.0 cm
of the working standard solution of phosphorus (V), which corresponds to 0,5; 1,0; 1,5 and 10 ág of phosphorus. Pour 2.5 cm
of concentrated hydrochloric acid and then act as described in section 4.1, conducting a measurement of optical density in relation to the simultaneously cooked «zero» solution containing all reagents except the standard solution of phosphorus.
On the found values of optical density and corresponding mass of phosphorus build a calibration curve.
5. PROCESSING OF THE RESULTS
5.1. Mass fraction of phosphorus () in percent is calculated by the formula
where is the mass of phosphorus was found in the calibration schedule, mcg;
— capacity volumetric flasks, cm
;
— aliquotes volume of the solution taken for the determining, cm
;
— the weight of the portion of the sample,
5.2. The values of permissible differences are listed in table.2.
Table 2
| Mass fraction of phosphorus, % |
The allowable divergence, % |
5·10 |
2·10 |
10·10 |
3·10 |
10·10 |
2·10 |
5·10 |
1·10 |
(Changed edition, Rev. N 1).
