GOST 19863.8-91
GOST 19863.8−91 Alloy of titanium. Methods for determination of molybdenum
GOST 19863.8−91
Group B59
STATE STANDARD OF THE USSR
ALLOYS OF TITANIUM
Methods for determination of molybdenum
Titanium alloys.
Methods for the determination of molybdenum
AXTU 1709
Date of introduction 1992−07−01
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; L. A. Tenyakova; M. N. Gorlova, PhD. chem. Sciences; A. I. Korolev, L. V. Antonenko;. Skorska O. L., Cand. chem. Sciences
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee on management of quality and standards from 5.05.91 N 625
3. REPLACE GOST 19863.8−80
4. The frequency of inspection — 5 years
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced |
Item number |
| GOST 3118−77 |
2.2; 3.2; 4.2 |
| GOST 3759−75 |
3.2 |
| GOST 3760−79 |
4.2 |
| GOST 4165−78 |
4.2 |
| GOST 4204−77 |
2.2; 4.2 |
| GOST 4461−77 |
2.2; 3.2; 4.2 |
| GOST 5456−79 |
3.2 |
| GOST 5457−75 |
3.2 |
| GOST 6344−73 |
2.2; 4.2 |
| GOST 9656−75 |
2.2; 3.2 |
| GOST 10484−78 |
2.2; 3.2; 4.2 |
| GOST 10929−76 |
4.2 |
| GOST 17746−79 |
3.2 |
| GOST 25086−87 |
1.1 |
| GOST 27067−86 |
4.2 |
| THAT 48−19−69−80 |
2.2; 3.2; 4.2 |
This standard specifies the photometric (with a mass fraction of from 0.01 to 15.0%), atomic absorption (at a mass fraction of from 0.05 to 15.0%) and differential photometric (at a mass fraction of from 28 to 36%) methods for determination of molybdenum.
1. GENERAL REQUIREMENTS
1.1. General requirements for methods of analysis GOST 25086 with the Supplement.
1.1.1. For the results analysis be the arithmetic mean of results of two parallel measurements.
2. THE PHOTOMETRIC METHOD FOR THE DETERMINATION OF MOLYBDENUM
2.1. The essence of the method
The method is based on dissolving the sample in a mixture of solutions of sulfuric and bridgestation acid or sulfuric acid, the recovery of hexavalent molybdenum to pentavalent unitiola, education in the solution of hydrochloric acid 1,5−2,0 mol/DMyellow colored complex compound of molybdenum with unitiola and measuring the optical density of the solution at a wavelength of 370 nm.
Interfere with the determination, palladium, rhenium and copper. The interfering effect of copper when the ratio of copper and molybdenum of 1:1, but the mass fraction of copper not more than 0.5% eliminate introduction of thiourea.
2.2. Apparatus, reagents and solutions
Spectrophotometer or photoelectrocolorimeter.
Sulfuric acid according to GOST 4204 density 1.84 g/cm, mortar is 1:2 and 7:93.
Hydrochloric acid according to GOST 3118 density of 1.19 g/cm, mortar 1:1 and 1 mol/DM
.
Nitric acid according to GOST 4461 density of 1,35−1,40 g/cmand a solution of 1:1.
Hydrofluoric acid according to GOST 10484.
Acid bridgestation: 280 cmhydrofluoric acid at a temperature of (10±2) °C add portions 130 g of boric acid and stirred. The reagent is prepared and stored in a plastic container.
Boric acid according to GOST 9656.
2,3-dimercaprol sodium (unithiol), a solution of 50 g/DM(suitable for working for two months when stored in a dark place in the flask with a glass stopper).
Thiourea according to GOST 6344, solution 100 g/DM.
Molybdenum high purity on the other 48−19−69 containing not less than 99.5% molybdenum.
Standard molybdenum solution: 0.1 g of molybdenum was placed in a conical flask with a capacity of 250 cm, flow 10 cm
of nitric acid and heated until complete dissolution. The solution is poured 20 cm
of sulfuric acid solution 1:2, evaporated to the appearance of dense white fumes and continue heating for 3 min.
The solution was cooled to room temperature, pour the 50 cmof water, stirred and evaporated again until the appearance of dense white fumes. To the cooled residue is poured 100 cm
of solution of sulfuric acid of 7:93, cooled to room temperature, poured into a measuring flask with volume capacity of 1000 cm
, made up to the mark with water and mix.
1 cmof the solution contains 0.0001 g mo
libgen.
2.3. Analysis
2.3.1. A portion of the sample weighing 1 g in accordance with table.1 is placed in a conical flask with a capacity of 250 cm, 30 cm, pour the
sulfuric acid solution of 1:2, 1 cm
bridgestation acid and moderately heated to complete dissolution.
Table 1
| Mass fraction of molybdenum, % |
The weight of the portion of the sample, g |
Capacity volumetric flasks, cm |
The volume aliquote part, see |
Length of the cell, mm |
| From 0.01 to 0.1 incl. |
1 |
100 |
10 |
50 |
| SV. 0,1 «0,5 « |
0,5 |
100 |
5 |
50 |
| «0,5» 1,0 « |
0,5 |
250 |
10 |
10 |
| «Of 1.0» to 4.0 « |
0,5 |
250 |
5 |
10 |
| «A 4.0» and 10.0 « |
0,5 |
250 |
2,5 | 10 |
| «A 10.0» to 15.0 « |
0,25 |
250 |
2,0 |
10 |
A portion of the sample weight of 0.5 or 0.25 g in accordance with table.1 is dissolved in 30 cmof sulfuric acid solution of 1:2 under heating.
The solution was added dropwise nitric acid until the disappearance of violet colour, 2−3 drops in excess, is evaporated until the appearance of dense white fumes and continue heating for 2−3 min.
The solution was cooled to room temperature, carefully pour 50 cmof water and boil for 1−2 min.
If the chrome alloy operation of evaporation and boiling is repeated.
The solution was cooled to room temperature, transferred into a measuring flask with volume capacity in accordance with table.1, made up to the mark with water and mix.
2.3.2. Aliquot part of the solution is placed in a volumetric flask with a capacity of 50 cm, flow 15 cm
of a hydrochloric acid solution of 1:1, 5 cm
of a solution of unithiol, made up to the mark with water and mix.
2.3.3. When a copper alloy to aliquote part of the solution in a volumetric flask with a capacity of 50 cmpour 15 cm
of a solution of thiourea, is aged 10 minutes, poured 10 cm
of hydrochloric acid of 1:1, 3 cm
of a solution of unithiol, made up to the mark with water and mix.
2.3.4. Optical density of the solution is measured after 10 minutes, but no later than 50 min at a wavelength of 370 nm in cuvettes with a thickness of fotometricheskogo layer in accordance with the table.1. Solution comparison is the solution of the reference experiment with all used in the analysis reagents.
2.3.5. Mass fraction of molybdenum is calculated according to the calibration schedule.
2.3.6. Construction of calibration curve
2.3.6.1. When the mass fraction of molybdenum from 0.01 to 0.5%
Nine volumetric flasks with a capacity for 50 cmflow at 5 cm
or 10 cm
of the solution in the reference experiment, eight of them measure 0,1; 0,2; 0,4; 0,6; 0,8; 1,0; 1,2; 1,4 cm
standard solution of molybdenum, which corresponds to 0,00001; 0,00002; 0,00004; 0,00006; 0,00008; 0,0001; 0,00012; 0,00014 g of molybdenum, and continue on PP.2.3.2 and
2.3.6.2. When the mass fraction of molybdenum from 0.5 to 15.0%
In ten volumetric flasks with a capacity of 50 cmpour 5 cm
of the solution in the reference experiment, nine of them measure 0,5; 1,0; 2,0; 3,0; 4,0; 5,0; 6,0; 7,0; 8,0 cm
standard solution of molybdenum, which corresponds to 0,00005; 0,0001; 0,0002; 0,0003; 0,0004; 0,0005; 0,0006; 0,0007; 0,0008 g of molybdenum, pour 15 cm
of a hydrochloric acid solution 1:1 and continue at PP.2.3.2 and
Solutions comparison are the solutions that you have not entered the molybdenum.
According to the obtained values of optical density of the solutions and their corresponding masses of molybdenum to build the calibration graph.
2.4. Processing of the results
2.4.1. Fraction of total mass of molybdenum () in percent is calculated by the formula
where is the mass of molybdenum in the sample solution found by the calibration schedule g;
the sample mass in the corresponding aliquote part of the solution,
2.4.2. Discrepancies in the results must not exceed the values given in table.2.
Table 2
| Mass fraction of molybdenum, % |
The absolute allowable difference, % | |
| results of parallel measurements |
the results of the analysis | |
| From 0,010 to 0,030 incl. |
0,005 |
0,007 |
| SV. 0,030 «to 0,060 « |
0,007 |
0,009 |
| «Of 0.06» to 0.15 « |
0,01 |
0,02 |
| «Of 0.15» to 0.30 « |
0,02 |
0,03 |
| «Of 0.30» to 0.60 « |
0,03 |
0,04 |
| «0,60» 1,50 « |
0,06 |
0,07 |
| «Of 1.50» to 3.00 « |
0,08 |
0,10 |
| «To 3.00» 5,00 « |
0,15 |
0,20 |
| «Of 5.00» to 10.00 « |
0,25 |
0,30 |
| «A 10.0» to 15.0 « |
0,3 |
0,4 |
3. ATOMIC ABSORPTION METHOD FOR THE DETERMINATION OF MOLYBDENUM
3.1. The essence of the method
The method is based on dissolving the sample in hydrochloric and bridgestation acids and measuring the nuclear absorption of molybdenum at a wavelength of 313,3 nm in a flame acetylene — nitrous oxide.
3.2. Apparatus, reagents and solutions
Spectrophotometer of atomic absorption with a source of radiation for molybdenum.
Acetylene according to GOST 5457.
Nitrous oxide medical.
Hydrochloric acid according to GOST 3118 density of 1.19 g/cmand a solution of 2:1, 1:1.
Nitric acid according to GOST 4461 density of 1,35−1,40 g/cm.
Boric acid according to GOST 9656.
Hydrofluoric acid according to GOST 10484.
Acid bridgestation: 280 cmhydrofluoric acid at a temperature of (10±2) °C add portions 130 g of boric acid and stirred. The reagent is prepared and stored in a plastic container.
Aluminium chloride according to GOST 3759, a solution of 100 g/DM.
Hydroxylamine hydrochloride according to GOST 5456, a solution of 200 g/DM.
Titanium sponge according to GOST 17746* stamps TG-100.
_______________
* On the territory of the Russian Federation GOST 17746−96. — Note the manufacturer’s database.
Solutions of titanium.
Solution A, 20 g/DM: 4 g of titanium was placed in a conical flask with a capacity of 250 cm
, 160 cm add a
solution of hydrochloric acid 2:1, 4 cm
bridgestation acid and dissolved with moderate heating. After dissolution of the sample add 8 cm
of a solution of hydroxylamine hydrochloride, and boil the solution for 1 min. the Solution was cooled to room temperature, transferred to a volumetric flask with a capacity of 200 cm
, made up to the mark with water and mix.
Solution B, 10 g/l, 1 g of titanium was placed in a conical flask with a capacity of 250 cm
, add 80 cm
of a hydrochloric acid solution of 2:1, 4 cm
bridgestation acid and dissolved with moderate heating. After dissolution of the sample add 4 cm
of a solution of hydroxylamine hydrochloride, and boil the solution for 1 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.
Solution, 4 g/DM: 0.4 g of titanium was placed in a conical flask with a capacity of 250 cm
, add 80 cm
of a hydrochloric acid solution of 2:1, 4 cm
bridgestation acid and dissolved with moderate heating. After dissolution of the sample add 4 cm
of a solution of hydroxylamine hydrochloride, and boil the solution for 1 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.
Molybdenum high purity on the other 48−19−69 containing not less than 99.5% molybdenum.
Standard solutions of molybdenum
Solution a: 0.5 g of molybdenum were placed in a glass with a capacity of 150 cm, flow 20 cm
of a mixture of hydrochloric and nitric acids in the ratio 3:1 and dissolved under moderate heating. After dissolution, the sample solution is evaporated to dry salts, add 20 cm
of water and again evaporated to dry salts. The operation of removal of nitrogen oxides again. The dry residue is dissolved in 100 cm
of a hydrochloric acid solution 1:1 with moderate heating, the solution was cooled to room temperature and transfer the contents of the Cup into a measuring flask with a capacity of 500 cm
, made up to the mark with water and mix.
1 cmof the solution contains 0.001 g of molybdenum.
Solution B: 20 cmsolution And placed in a volumetric flask with a capacity of 100 cm
, pour 2 cm
of hydrochloric acid 1:1, made up to the mark with water and mix.
1 cmof a solution contains 0.0002 g of molybdenum.
Solution: 2.5 cmmortar And placed in a volumetric flask with a capacity of 100 cm
, pour 2 cm
of hydrochloric acid 1:1, made up to the mark with water and mix.
1 cmof the solution In
contains 0,000025 g of molybdenum.
3.3. Analysis
3.3.1. A portion of the sample weight in accordance with table.3 is placed in a conical flask with a capacity of 100 cm, flow 20 cm
of a hydrochloric acid solution of 2:1, 1 cm
bridgestation acid and dissolved with moderate heating.
Table 3
| Mass fraction of molybdenum, % |
The weight of the portion of the sample, g |
| From 0.05 to 1.0, incl. |
0,5 |
| SV. 1,0 «5,0 « |
0,25 |
| «A 5.0» to 15.0 « |
0,1 |
After dissolution of the sample add 1 cmof a solution of hydroxylamine hydrochloride, and boil the solution for 1 min. the Solution was cooled to room temperature, transferred to a volumetric flask with a capacity of 250 cm
, 5 cm pour the
hydrochloric acid solution of 1:1, 25 cm
of a solution of aluminum chloride, made up to the mark with water and mix.
When the mass fraction of molybdenum from 0.05 to 0.25% solution after cooling to room temperature, transferred to a volumetric flask with a capacity of 100 cm, pour 2 cm
of hydrochloric acid 1:1, 10 cm
of a solution of aluminum chloride, made up to the mark with water and mix
.
3.3.2. The solution in the reference experiment is prepared according to claim
3.3.3. Construction of calibration curve
3.3.3.1. When the mass fraction of molybdenum from 0.05 to 0.25%
In six volumetric flasks with a capacity of 100 cmpoured in 25 cm
of a solution of titanium And, in five of them measure 1,0; 2,0; 3,0; 4,0; 5,0 cm
standard solution, which corresponds to 0,000025; 0,00005; 0,000075; 0,0001; 0,000125 g of molybdenum.
3.3.3.2. When the mass fraction of molybdenum from 0.25 to 1.0%
In six volumetric flasks with a capacity of 100 cmpour 10 cm
of a solution of titanium And, in five of them measure 2,0; 4,0; 6,0; 8,0; 10,0 cm
standard solution B, which corresponds to 0.0004 inch; 0,0008; 0,0012; 0.0016 inch; 0.002 g of molybdenum.
3.3.3.3. When the mass fraction of molybdenum in excess of 1.0 to 5.0%
In six volumetric flasks with a capacity of 100 cmpour 10 cm
of a solution of titanium Used, five of them measure 1,0; 2,0; 3,0; 4,0; 5,0 cm
standard solution A, which corresponds to 0,001; 0,002; 0,003; 0,004; 0.005 g of molybdenum.
3.3.3.4. When the mass fraction of molybdenum over 5.0 to 10.0%
In six volumetric flasks with a capacity of 100 cmplaced at 10 cm
of the solution of titanium In five of them measure 2,0; 2,5; 3,0; 3,5; 4,0 cm
standard solution A, which corresponds to 0,002; 0,0025; 0,003; 0,0035; 0.004 g of molybdenum.
3.3.3.5. When the mass fraction of molybdenum over 10.0 to 15.0%
In six volumetric flasks with a capacity of 100 cmplaced at 10 cm
of the solution of titanium In five of them measure 4,0; 4,5; 5,0; 5,5; 6,0 cm
standard solution A, which corresponds to 0.004 inch; 0,0045; 0,005; 0,0055; 0.006 g of molybdenum.
3.3.3.6. The solutions in flasks (see PP.3.3.3.1; of hydrochloric acid 1:1, 10 cm
of a solution of aluminum chloride, made up to the mark with water and mix.
3.3.4. The sample solution, solution control experience and solutions to build the calibration curve is sprayed into the flame of acetylene — nitrous oxide and measure the atomic absorption of molybdenum at a wavelength of 313,3 nm.
According to the obtained values of atomic absorption and corresponding mass concentrations of molybdenum are building a calibration curve in the coordinates «Value of atomic absorption — Mass concentration of molybdenum, g/cm».
The mass concentration of molybdenum in the sample solution and the solution of control and experience determined by the calibration schedule.
3.4. Processing of the results
3.4.1. Fraction of total mass of molybdenum () in percent is calculated by the formula
where is the mass concentration of molybdenum in the sample solution found by the calibration schedule, g/cm
;
— mass concentration of molybdenum in solution in the reference experiment, was found in the calibration schedule, g/cm
;
— the volume of the sample solution, cm
;
— weight of sample, g
.
3.4.2. Discrepancies in the results must not exceed the values given in table.4.
Table 4
| Mass fraction of molybdenum, % |
The absolute allowable difference, % | |
| results of parallel measurements |
the results of the analysis | |
| From 0.05 to 0.10 incl. |
0,01 |
0,02 |
| SV. Of 0.10 «to 0.25 « |
0,02 |
0,03 |
| «0,25» 0,50 « |
0,03 |
0,05 |
| «0,50» 1,00 « |
0,05 |
0,10 |
| «To 1.00» to 2.50 « |
0,10 |
0,15 |
| «Of 2.50» and 5.00 « |
0,15 |
0,20 |
| «Of 5.00» to 10.00 « |
0,25 |
0,30 |
| «A 10.0» to 15.0 « |
0,3 |
0,4 |
4. DIFFERENTIAL PHOTOMETRIC METHOD FOR THE DETERMINATION OF MOLYBDENUM
4.1. The essence of the method
The method is based on dissolving the sample in a mixture of nitric and bridgestation acids, the formation in solution of hydrochloric acid 3 mol/DMorange complex of pentavalent molybdenum with ammonium radamisty and measuring the optical density of the solution at a wavelength of 460 nm.
4.2. Apparatus, reagents and solutions
Spectrophotometer or photoelectrocolorimeter.
Hydrochloric acid according to GOST 3118 density of 1.19 g/cm, a solution of 1:1.
Nitric acid according to GOST 4461 density of 1,35−1,40 g/cm, a solution of 1:1.
Boric acid according to GOST 9656.
Hydrofluoric acid according to GOST 10484.
Acid bridgestation: 280 cmhydrofluoric acid at a temperature of (10±2) °C add portions 130 g of boric acid and stirred. The reagent is prepared and stored in a plastic container.
Sulfuric acid according to GOST 4204 density 1.84 g/cm, a solution of 1:3.
Hydrogen peroxide according to GOST 10929.
Thiourea according to GOST 6344, solution 100 g/DM.
Ammonium radamisty according to GOST 27067, a solution of 500 g/DM.
Ammonia water according to GOST 3760.
Copper (II) sulfate 5-water according to GOST 4165, a solution of 20 g/DM.
Molybdenum high purity on the other 48−19−69 containing not less than 99.5% molybdenum.
A standard solution of molybdenum, 1 g of molybdenum was placed in a conical flask with a capacity of 100 cm, flow 10 cm
of hydrogen peroxide and moderately heated to dissolve. The solution is poured 10 cm
of ammonia and boil in low heat until discoloration. The operation of boiling with ammonia is repeated twice.
The walls of the flask is washed with 30 cmof water, the solution was cooled to room temperature and poured into a measuring flask with volume capacity of 1000 cm
, made up to the mark with water and mix.
1 cmof the solution contains 0.001 g mol
ebden.
4.3. Analysis
4.3.1. A portion of sample weighing 0.25 g was placed in a conical flask with a capacity of 100 cm, 10−15 cm pour the
nitric acid solution, add dropwise 2 cm
bridgestation acid and dissolve in low heat.
The solution was poured 60 cmof sulfuric acid solution, heated to highlight the thick white fumes of sulfuric acid and heating was continued for 3 min. the Solution was cooled to room temperature, the walls of the flask carefully poured in small portions 50 cm
of water, again cool the solution to room temperature, transferred to a volumetric flask with a capacity of 250 cm
, made up to the mark with water and mix.
4.3.2. Aliquot part of the solution is 4.0 cm, containing from 1.1 to 1.5 mg of molybdenum, transferred to a volumetric flask with a capacity of 50 cm
, 25 cm pour the
hydrochloric acid solution, 1.5 cm
of a solution of sulphate of copper, 15 cm
of a solution of thiourea and stirred. After 10 minutes, pour 2 cm
of Rodenstock ammonium solution, made up to the mark with water and mix.
4.3.3. Optical density of the solution is measured after 15 min at a wavelength of 460 nm in cuvettes with a thickness of fotometricheskogo layer 5 mm, having strictly the same working length.
The comparison solution is a solution containing 1.1 mg molybdenum 50 cm, which is prepared according to claim
Fraction of total mass of molybdenum, calculated according to the calibration schedule.
4.3.4. Construction of calibration curve
Five volumetric flasks with a capacity of 50 cmmeasured to 1,1; 1,2; 1,3; 1,4; 1,5 cm
of a standard solution of molybdenum, which corresponds to the 1,1; 1,2; 1,3; 1,4; 1,5 mg of molybdenum, poured 25 cm
hydrochloric acid solution and then continue on PP.4.3.2 and
According to the obtained values of optical density of the solutions and their corresponding masses of molybdenum to build the calibration graph.
4.4. Processing of the results
4.4.1. Fraction of total mass of molybdenum () in percent is calculated by the formula
where is the mass of molybdenum in the sample solution found by the calibration schedule g;
— weight of sample in aliquote part of the solution,
4.4.2. Allowable absolute differences must not exceed: results of parallel measurements for 0.5%; the results of the analysis — 0,6%.
