GOST 12553.1-77
GOST 12553.1−77 Alloys of platinum-palladium. Method of determining palladium (with Change No. 1)
GOST 12553.1−77
Group B59
STATE STANDARD OF THE USSR
ALLOYS, PLATINUM-PALLADIUM
Method for the determination of palladium
Platinum-palladium alloys. Method for the determination of palladium
AXTU 1709*
______________
* Introduced advanced Edit. N 1.
Valid from 01.01.1979
to 01.01.1984*
_________________________________
* Expiration removed by Protocol No. 3−93
The interstate Council for standardization,
Metrology and certification (ICS No. 5/6, 1993). -
Note the manufacturer’s database.
DEVELOPED by Sverdlovsk factory on processing of nonferrous metals
Director S. G. Gushchin
Heads V. G. Levin, V. D. Ponomareva
Performers: M. P. Yufa, A. I. Osintseva, R. M. Bogdanova
INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
Zam. Minister V. S. Ustinov
The draft all-Union scientific research Institute of standardization (VNIIS)
Director A. V. Gichev
APPROVED AND promulgated by the Decree of the State Committee of standards of the USSR Council of Ministers dated 27 December 1977, N 3070
REPLACE GOST 12553−67 in part of sec. 2
The Change N 1, approved and put into effect by the Decree of the USSR State Committee for standards from
Change No. 1 made by the manufacturer of the database in the text IUS N 8, 1988
This standard specifies the titrimetric method for the determination of palladium (with mass fraction of palladium from 10.0 to 40%).
The method is based on the binding of a palladium complex compound dwuzameshchenny the sodium salt of ethylenediaminetetraacetic acid (Trilon B) at pH 5 and titrate the excess Trilon B with a solution of acetate of zinc with indicator xylinum orange.
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 22864−83.
(Changed edition, Rev. N 1).
1.2. The numerical value of the result of the analysis must end with a digit of the same rank as that of the normalized indicator grade composition.
(Added, Rev. N 1).
2. APPARATUS, REAGENTS AND SOLUTIONS
Laboratory scales lever according to GOST 24104−80*.
_____________
* On the territory of the Russian Federation GOST 24104−2001. — Note the manufacturer’s database.
Conical flasks with a capacity of 250 cmaccording to GOST 25336−82.
Volumetric flasks with a capacity of 250 cmaccording to GOST 1770−74.
Burette with automatic zero setting capacity of 50 cm.
Pipettes with a capacity of 10, 20, 25 cmaccording to GOST 20292−74*.
______________
* On the territory of the Russian Federation there are 29169−91 GOST, GOST 29227−91−29229−91 GOST, GOST 29251−91-GOST 29253−91. — Note the manufacturer’s database.
Hydrochloric acid by the GOST 3118−77.
Nitric acid GOST 4461−77.
A mixture of acids, consisting of one volume of nitric acid and three volumes of hydrochloric acid.
Sodium acetate according to GOST 199−78, a solution with a mass fraction of 50%.
Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid, 2-water (Trilon B) according to GOST 10652−73, 0,075 mol/DMsolution; prepared as follows: 27,9 g of salt is dissolved by heating in 500 cm
of water and bring the volume to 1 l with water.
Zinc acetate according to GOST 5823−78, 0.1 mol/DMsolution; prepared as follows: to 9.15 g of salt dissolved in 500 cm
of water and bring the volume to 1 l with water.
Selenology orange indicator solution with a mass fraction of 0.2%.
Palladium brand PD 99,9 GOST 13462−79, standard solution; is prepared as follows: 5,0000 g of palladium was dissolved with heating in 30 cmof a mixture of acids, was transferred to a volumetric flask with a capacity of 500 cm
, made up to the mark with water and mix.
1 cmof the solution contains 0.01 g of palladium.
(Changed edition, Rev. N 1).
3. PREPARATION FOR ASSAY
Two sample alloy (in the form of strips or chips) weighing 2.5 g placed in a conical flask with a capacity of 250 cm, was dissolved with heating in 100 cm
of the mixture of acids and evaporated to 50 cm
.
(Changed edition, Rev. N 1).
4. ANALYSIS
4.1. Setting the ratio of Trilon B with acetic acid zinc
Pipette or burette take 10 cmof the solution Trilon B, is placed in a conical flask with a capacity of 250 cm
, flow 20 cm
water, 5 cm
of a solution of sodium acetate, 10 drops of the indicator solution kylinalove orange and titrated with a solution of zinc acetate until the color of solution from yellow to crimson. At the same time three definitions.
Ratio () is calculated by the formula
where — volume of solution Trilon B, cm
;
— the volume of solution of acetate of zinc, cm
.
4.2. Determination of the titer of the solution Trilon B at the palladium
20 cmstandard solution palladium was placed in a conical flask with a capacity of 250 cm
, poured with a pipette or a burette 40 cm
of the solution Trilon B, 30 cm
water, 10 cm
of a solution of sodium acetate, 10 drops of the indicator solution kylinalove orange and titrated with a solution of zinc acetate until the color of solution from yellow to bright red.
Caption (), expressed in g/cm
of palladium, calculated by the formula
where is the mass of palladium contained in 20 cm
standard solution, g;
— volume of solution Trilon B, cm
;
— the volume of solution of acetate of zinc, consumed in the titration, cm
;
the ratio of Trilon B with acetic acid zinc
.
4.1, 4.2. (Changed edition, Rev. N 1).
4.3. Definition of palladium
Prepared for analysis the analyzed alloy solution is transferred into a measuring flask with a capacity of 250 cm, was adjusted to the mark with water and mix thoroughly.
Of take volumetric flasks pipette two aliquots of 25 cmthat is placed in a conical flask with a capacity of 250 cm
. Then into the solution poured with a pipette or a burette 40 cm
of the solution Trilon B, 20 cm
of water and 20 cm
of a solution of sodium acetate to create a pH of 5.
Excess Trilon B octarepeat solution of zinc acetate in the presence of the indicator solution kylinalove orange (10 drops) until the color of solution from yellow to bright red.
(Changed edition, Rev. N 1).
5. PROCESSING OF THE RESULTS
5.1. Mass fraction of palladium () in percent is calculated by the formula
where is the number of solution Trilon B added for the formation of complex palladium, cm
;
— number of solution of acetate of zinc consumed for titration of the excess of the solution Trilon B, cm
;
the ratio of Trilon B with acetic acid and zinc;
the titer of the solution Trilon B at the palladium, g/cm
;
— weight of alloy, suitable aliquote part,
(Changed edition, Rev. N 1
).
5.2. Allowable absolute differences between the results of parallel measurements (the rate of convergence) at a confidence probability
of 0.95, should not exceed 0.20%.
Absolute differences average results of determinations obtained in two different laboratories (a measure of reproducibility) shall not exceed 0.30 percent.
(Changed edition, Rev. N 1).
5.3. The control of correctness of analysis results
Control of the correctness of the results of determining the mass fraction of palladium is playing its mass fraction in the artificial mixtures the chemical composition close to the composition of the analyzed alloy, drawn through the entire course of the analysis.
The sample analysis results are considered correct if the absolute difference between the maximum and minimum values of the mass fraction of palladium in the synthetic mixtures does not exceed 0.11 percent.
(Added, Rev. N 1).
