GOST 2604.9-83

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  ГОСТ 2604.9-83

GOST 2604.9−83 Cast iron alloy. Methods for determination of copper (with Change No. 1)

GOST 2604.9−83

Group B09

INTERSTATE STANDARD

ALLOY CAST IRON

Methods for determination of copper

Alloy cast iron. Methods for determination of copper

ISS 77.080.10
AXTU 0809

Date of introduction 1984−07−01

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Ministry of ferrous metallurgy of the USSR

DEVELOPERS

Yu. S., Chernobrovina, T. A. Butenko, P. A. Parkhomenko, A. S. Grzegorzewski, V. P. Korzh, J. B. Kulikov, B. A., Sorochinskaya, L. N. Novak

2. APPROVED AND promulgated by the Decree of the State Committee of standards of Ministerial Council of the USSR from 08.07.83 N 680

3. REPLACE GOST 2604.9−77

4. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS

5. Limitation of actions taken by Protocol No. 3−93 Interstate Council for standardization, Metrology and certification (ICS 5−6-93)

6. EDITION with Change No. 1, approved in December 1988 (IUS 3−89)


This standard sets the photometric method for the determination of copper (at a mass fraction of from 0.05 to 1.0%), titrimetric method for the determination of copper (at a mass fraction of from 1.0 to 4.0%) and atomic absorption method for the determination of copper (at a mass fraction of from 0.10 to 4.0%) in the doped iron.

1. GENERAL REQUIREMENTS

1.1. General requirements for methods of analysis GOST 28473.

1.2. The error of the result of the analysis (under confidence probability =0,95) does not exceed the limit given in table.2, when the following conditions are met:

the discrepancy between the results of two (three) parallel dimensions should not exceed (with a confidence probability =0,95) of the values given in table.2;

played in the standard sample, the value of the mass fraction of the element must not vary from certified more than acceptable (at a confidence level =0,85) the value given in table.2.

If any of the above conditions, a second measurement of the mass fraction of copper. If in repeated measurements the precision requirement of the results are not met, the results of the analysis recognize the incorrect measurements cease to identify and eliminate the causes of violation of the normal course of analysis.

The divergence of the two middle results of an analysis performed under different conditions (for example, when the control intralaboratory reproducibility) shall not exceed (with a confidence probability =0,95) of the values given in table.2.

(Added, Rev. N 1).

2. PHOTOMETRIC METHOD

2.1.The essence of the method

The method is based on the formation in ammonia solution (pH of 8.5−9.0) painted in yellow color and stabilized with gelatin complex compounds of copper (II) with diethyldithiocarbamate sodium. The interfering influence of iron, chromium, Nickel, vanadium, molybdenum, manganese, aluminum, eliminate the preliminary separation of copper as a sulfide Chernovetskiy sodium and adding citric acid and Trilon B.

2.2. Apparatus, reagents and solutions

Spectrophotometer, photoelectrocolorimeter, or spectropolarimeter.

Hydrochloric acid according to GOST 3118 and diluted 1:1.

Sulfuric acid according to GOST 4204 and diluted 1:1, 1:4, 1:50.

Nitric acid according to GOST 4461 and diluted 1:1.

Ammonia water according to GOST 3760.

Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid, 2-water (Trilon B) according to GOST 10652, a solution of 10 g of Trilon B dissolved in low heat in 100 cmof water and filtered.

Citric acid according to GOST 3652, a solution with a mass concentration of 0.15 g/cm.

Sodium N, N-diethyldithiocarbamate according to GOST 8864, solution with the mass concentration of 0.005 g/cm, freshly prepared.

Carbonyl iron OS.h.

Copper according to GOST 546.

Copper sulfate; a standard solution with A mass concentration of 1 mg/cmstandard solution B with a mass concentration of copper is 0.1 mg/cm.

Solution a: 1 g of copper is dissolved by heating in 20−25 cmof nitric acid (1:1), add 30 cmof sulphuric acid (1:1), evaporated to release its vapors, and cooled. Carefully with constant stirring, add 100 cmof water and heated to dissolve the salts. The solution was transferred to a volumetric flask with a capacity of 1 DM, cooled, made up to the mark with water and mix.

Solution B: 10 cmsolution And placed in a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

Sodium Chernovetskiy, a solution with a mass concentration of 0.3 g/cm.

Potassium preservatory according to GOST 7172.

Gelatin GOST 11293, solution with a mass concentration of 0.01 g/cm, freshly prepared.

(Revised edition, Edit

. N 1).

2.3. Analysis

2.3.1. The weight of cast iron weighing 0.2 g were placed in a glass or flask with a capacity of 250−300 cm, flow 50 cmof sulphuric acid (1:4), cover with a watch glass, and dissolve when heated. Upon completion of the dissolution gently pour 3−5 cmof nitric acid and evaporated until the appearance of sulphuric acid fumes. If cast iron is not soluble in sulfuric acid, the portion dissolved in 20 cmof hydrochloric acid (1:1) and 5−10 cmof nitric acid; carefully pour 15 cmof sulphuric acid (1:1) and evaporated the solution until the appearance of sulphuric acid fumes. The contents of the beaker or flask is cooled, carefully poured, with stirring, 80−100 cmof water, heated to dissolve the salts and filtered, the precipitate on the filter «white ribbon». Precipitate was washed 7−8 times with hot sulfuric acid (1:50), collecting the filtrate and wash liquid in a glass with a capacity of 300−400 cm. Filter the precipitate discarded.

To the resulting hot solution is poured 40−50 cmof a solution of sodium servational and boil until complete coagulation of the precipitate of copper sulfide and sulfur and enlightenment solution.

The solution with precipitate was cooled, the precipitate was filtered off on filter «white ribbon» and washed 6−8 times with hot water. The filter with precipitate was placed in a porcelain crucible, dried and incinerated. The precipitate was calcined at 500−550 °C and melted with 2−3 g of potassium peacemaking. The smelt is leached in 25−30 cmof hydrochloric acid (1:1). The solution is heated until complete dissolution of water, transferred to a volumetric flask with a capacity of 100 cm, cooled, made up to the mark with water and mix. The solution was filtered through two dry filter «white ribbon» in a dry flask, discarding first portion of filtrate. Aliquot part of the solution in accordance with the table.1 is placed in a volumetric flask with a capacity of 100 cm, add 5 cm, the citric acid solution, 10 cmof the solution Trilon B, 5 cmgelatin solution and 15 cmof water of ammonia, after addition of each reagent the solution was stirred. Add 10 cmof a solution of sodium diethyldithiocarbamate, made up to the mark with water and mix.

Table 1

Optical density of the solution measured on a spectrophotometer at a =453 nm or photoelectrocolorimeter with a filter having a region of transmittance of wavelengths from 420 to 490 nm in a cuvette with the thickness of the absorbing layer is 50 mm. as a solution comparison solution is used in the reference experiment.

2.3.2. Construction of calibration curve

Six glasses or flasks with a capacity of 250−300 cmis placed 0.2 g carbonyl iron. Five beakers or flasks poured successively 2, 4, 8, 12 and 15 cmstandard solution B, which corresponds to 0,2; 0,4; 0,8; 1,2 and 1,5 mg of copper. The sixth beaker or flask serves for the control experience. Further analysis is carried out as specified in clause 2.3.1. For photometry taken aliquot part of the solution was 10 cm.

The found values of optical density and corresponding mass of copper to build the calibration graph.

2.3.1, 2.3.2. (Changed edition, Rev. N 1).

2.4. Processing of the results

2.4.1. Mass fraction of copper () in percent is calculated by the formula

,

where is the mass of copper was found in the calibration graphics mg;

the weight of cast iron, suitable fotometricheskoe aliquote part of the solution, mg.

2.4.2. Norms of accuracy and norms of accuracy control of determination of mass fraction of copper is given in table.2.

Table 2

2.4.1, 2.4.2. (Changed edition, Rev. N 1).

3. TITRIMETRIC METHOD

3.1. The essence of the method — according to GOST 12355.

3.2. Apparatus, reagents and solutions — according to GOST 12355.

3.3. Analysis — according to GOST 12355.

3.4. Processing of the results — according to GOST 12355 with the addition set out below.

3.4.1. Norms of accuracy and norms of accuracy control of determination of mass fraction of copper is given in table.2.

(Changed edition, Rev. N 1).

4. ATOMIC ABSORPTION METHOD

4.1. The essence of the method — according to GOST 12355.

4.2. Apparatus, reagents and solutions — according to GOST 12355.

4.3. Analysis — according to GOST 12355.

4.4. Processing of the results — according to GOST 12355 with the addition set out below.

4.4.1. Norms of accuracy and norms of accuracy control of determination of mass fraction of copper is given in table.2.

(Changed edition, Rev. N 1).