GOST 12697.10-77
GOST 12697.10−77 Aluminum. Method of determining titanium (with Amendments No. 1, 2, 3)
GOST 12697.10−77
Group B59
INTERSTATE STANDARD
ALUMINIUM
Method of determining titanium
Aluminium. Method for determination of titanium
ISS 77.120.10
AXTU 1709
Date of introduction 1979−01−01
The decision of the State standards Committee of the Council of Ministers of the USSR from
Limitation of actions taken by Protocol No. 3−93 Interstate Council for standardization, Metrology and certification (ICS 5−6-93)
REPLACE GOST 12706−67 in part of sec. 2
EDITION with Amendments No. 1, 2, 3 approved in December 1980, November 1985, may 1988 (IUS 3−81, 2−86, 8−88).
This standard sets the photometric method for the determination of titanium in aluminium (with the mass fraction of titanium from the 0.0003 to 0.2%).
The method is based on formation of colored complex compounds of titanium with diantipyrylmethane. Trivalent iron restore ascorbic acid.
Colored solution photometered in nm.
(Changed edition, Rev. N 1, 3).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 12697.1−77 and GOST 25086−87.
(Changed edition, Rev. N 2, 3).
2. APPARATUS, REAGENTS AND SOLUTIONS
Types photoelectrocolorimeter FEK-56M, PEC-60, KLF or the types of spectrophotometer SF-16, SF-26 or similar type.
Laboratory scales according to GOST 24104−88* 2nd accuracy class with the weighing error of 0.0002 g.
___________________
* From 1 July 2002 was put into effect GOST 24104−2001**.
** On the territory of the Russian Federation GOST R 53228−2008. — Note the manufacturer’s database.
Technical laboratory scales VLT-200 4th class of accuracy with a scale division of 0.01 g or similar type.
Muffle furnace with thermostat, providing a temperature of 1000 °C.
Hydrochloric acid by the GOST 3118−77, diluted 1:1 and 1 mol/DMsolution.
Sulfuric acid GOST 4204−77, diluted 1:1, 1:4 and 1:6 and 0.5 mol/DMsolution.
Nitric acid GOST 4461−77 and diluted 1:1.
The iron containing titanium, obtained by the carbonyl method.
A solution of ferric chloride with a mass fraction of 0.1%; prepared as follows: 0.5 g of iron was dissolved in hydrochloric acid, oxidized with a few drops of nitric acid when heated and diluted with water to 500 cm.
Diantipyrylmethane, a solution with a mass fraction of 5% in a solution of 1 mol/DMof hydrochloric acid to accelerate the dissolution or at loss of crystalline precipitate and the solution is heated to 40−50 °C. To stabilize the solution add 3−5 g of ascorbic acid solution stored in a vessel of dark color.
Ascorbic acid, freshly prepared solution with a mass fraction of 2%.
Sodium hydroxide according to GOST 4328−77, solutions with a mass fraction of 20 and 2%. Store in a plastic container.
Copper sulfate according to GOST 4165−78, a solution with a mass fraction of 5%.
Potassium preservatory according to GOST 7172−76.
Titanium dioxide.
The solutions of titanium are standard.
Solution A, prepared as follows: 0,1670 g calcined at 900 °C titanium dioxide is fused with twenty times the number peacemaking potassium until a clear melt in a platinum crucible. The smelt is leached when heated to 100 cmof sulphuric acid diluted 1:1, and after cooling transferred into a measuring flask with volume capacity of 1000 cm. Then pour 100 cmof sulphuric acid diluted 1:1, made up to the mark with water and stirred or 0.1 g of titanium dissolved in 20 cmof sulfuric acid solution 1:4, after dissolution, is oxidized with concentrated nitric acid added dropwise, and the solution evaporated to fumes of sulphuric anhydride. Then dissolve in water, add 100 cmof sulfuric acid solution 1:1 and transferred into a measuring flask with volume capacity of 1000 cmcontaining 100 cmof sulfuric acid solution 1:1, and stirred.
1 cmof solution A contains 0.1 mg of titanium (Ti).
Solution B is prepared before use as follows: pipette take 50 cmof solution A in a volumetric flask with a capacity of 500 cm, add sulphuric acid, diluted 1:6, to the mark and mix.
1 cmof a solution contains 0.01 mg of titanium (Ti).
Hydrofluoric acid according to GOST 10484−78.
Nickel chloride according to GOST 4038−79, a solution with a mass fraction of 0.2%.
The titanium metal.
Sec. 2. (Changed edition, Rev. N 1, 3).
3. ANALYSIS
3.1. Weighed aluminium weighing 2 g were placed in a glass with a capacity of 400 cm, flow 50 cmof hydrochloric acid diluted 1:1, and cover with a watch glass. After the violent reaction wash the glass and the side of the Cup with hot water and heated to dissolve sample. In the case of slow dissolution of aluminium in a glass add 1 cmof a solution of Nickel chloride.
After cooling, the beaker content was transferred into a measuring flask with a capacity of 100 cmcontaining 20 cmof sulfuric acid solution 1:1, dilute to the mark with water and mix thoroughly.
If the solution is not quite transparent, before transferring to volumetric flask the solution was filtered through filter «blue ribbon» in a glass containing 4 cmof sulfuric acid solution 1:1, washing filter and beaker several times with hot water.
The filter with precipitate was placed in a platinum crucible, dried, incinerated and calcined at 1000 °C. After cooling, to the residue add 2 cmof sulfuric acid solution 1:1, 3−5 cmhydrofluoric acid and 3−4 drops of concentrated nitric acid, evaporated, the residue calcined and fused with 0.5−1 g of potassium persulfate at 800 °C until a clear melt. After cooling, leached alloy 5 cmof sulfuric acid solution 1:6 when heated. The contents of the crucible poured to the filtrate, washing away a small amount of water, then evaporated the filtrate to a volume of 30−40 cm.
The cooled solution is transferred to a volumetric flask with a capacity of 100 cm, containing 15 cmof sulfuric acid solution, diluted 1:1, made up to the mark with water and mix.
Pipetted 5−50 cmof solution, depending on the assumed mass fraction of titanium in a volumetric flask with a capacity of 100 cmand dilute with water to 50 cm. Then poured with stirring 15 cmsulphuric acid diluted 1:1, 5 cmof ascorbic acid, 2 drops of solution of copper sulphate and after 5 min 10 cmdiantipyrylmethane solution, dilute the solution to the mark with water and mix. After 1 hour measure optical density of solution on a photoelectrocolorimeter or spectrophotometer, given that a maximum of light absorption of solutions corresponds to a wavelength of 385 nm.
Solution comparison is water.
At the same time spend control experience.
This 50 cmof hydrochloric acid diluted 1:1, evaporated to a glass to 5−10 cm, diluted with water, transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.
Select aliquot part of the solution corresponding to aliquote part of the study solution into a measuring flask with a capacity of 100 cmand carry out the analysis as described above.
The mass of titanium is determined according to the calibration schedule 1, taking into account the amendment in the reference experiment.
(Modified, edited by
I, ISM. N 1, 3).
3.2. For the determination of titanium in aluminum is high purity aluminum sample of mass 3 g is dissolved in 50 cmof sodium hydroxide solution with a mass fraction of 20% in a beaker with a capacity of 400 cm, covered with a watch glass.
At the end of the violent reaction of the glass and the side of the Cup is washed with hot water and heated to dissolve sample. Then pour 100 cmof hot water, 3 cmof a solution of ferric chloride, stirred and heated to coagulate the precipitate. The hot solution is filtered through a filter «white ribbon», the precipitate washed three times with hot sodium hydroxide solution with a mass fraction of 2%, and two or three times with water. Then wash off the residue from the filter with water in a glass with a capacity of 100 cm, the filter is washed with 10 cmof sulphuric acid, diluted 1:4, collecting the solution in the beaker with the sediment and filter washed two or three times with hot water. Then add 10 drops of nitric acid and evaporate the solution until the appearance of sulphuric acid fumes. If the rest of the glass is painted in yellow color, add drop by drop nitric acid prior to bleaching it, washed the walls of the glass with water and evaporated to the appearance of sulphuric acid fumes.
After cooling, to the residue poured 5 cmof sulfuric acid solution, diluted 1:6, and heated to dissolve the residue. After cooling, transfer the solution into a volumetric flask with a capacity of 25 cm, flow 3 cmof ascorbic acid solution and 2 drops of solution of copper sulphate and after 5 min, 5 cmdiantipyrylmethane solution, dilute to the mark with sulfuric acid, diluted 1:6, and stirred. Measurement of optical density produced as specified in claim 3.1.
At the same time spend control experience.
The mass of titanium is determined according to the calibration schedule 2, the amendment given in the reference experiment.
(Changed edition, Rev. N
3).
3.3. Construction of calibration graphs
3.3.1. Graph 1
In a volumetric flask with a capacity of 100 cmpoured from microburette 0; 1; 2; 4; 6; 8; 10; 15 and 20 cmof solution B, which corresponds to 0; 0,010; 0,020; 0,040; 0,060; 0,080; 0,100; 0,150 and 0.200 mg of titanium, add 2 cmof hydrochloric acid diluted 1:1 and diluted with water to 50 cmand further analysis is carried out as specified in clause 3.1.
Solution comparison is the solution in which the titanium was not added. According to the obtained values of optical density and known mass of titanium to build the calibration graph 1.
(Changed edition, Rev. N 1, 3).
3.3.2. Chart 2
In a volumetric flask with a capacity of 25 cmpoured from microburette 0; 0,5; 1; 2; 3; 4; 5 cmof solution B, which corresponds to 0; 0,005; 0,010; 0,020; 0,030; 0,040; 0,050 mg titanium.
To each flask add 10 cmsulphuric acid, diluted 1:6, and further conduct an analysis as specified in paragraph 3.2.
Solution comparison is the solution in which the titanium was not added. According to the obtained values of optical density and known mass of titanium to build the calibration graph 2.
(Changed edition, Rev. N 3).
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of titanium () in percent is calculated by the formula
,*
________________
* Formula conforms to the original. — Note the manufacturer’s database.
where is the mass of titanium, was found in the calibration graphics mg;
— the total volume of solution, cm;
— volume aliquote part of the solution, cm;
the weight of aluminium,
4.2. Permissible discrepancies in the results of parallel definitions should not exceed the values given in the table.
Mass fraction of titanium, % |
Allowable difference, % | |
convergence Rel. |
reproducibility, Rel. | |
From the 0.0003 to 0.005 incl. |
30 |
45 |
SV. Of 0.005 «to 0.05 « |
20 |
30 |
«0,05» 0,1 « |
10 |
15 |
«0,1» 0,2 « |
5 |
10 |
(Changed edition, Rev. N 1, 3).