GOST 31382-2009

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  ГОСТ 31382-2009

GOST 31382−2009 Copper. Methods of analysis

GOST 31382−2009

Group B59

INTERSTATE STANDARD

COPPER

Methods of analysis

Copper. Methods of analysis

ISS 77.120.30
GST 17 3320
AXTU 1709

Date of introduction 2010−04−01

Preface

Goals, basic principles and main procedure of works on interstate standardization have been established in GOST 1.0−92 «interstate standardization system. Basic provisions» and GOST 1.2−97 «interstate standardization system. Interstate standards, rules and recommendations on interstate standardization. The procedure of development, adoption, application, renewal and cancellation"*
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* On the territory of the Russian Federation GOST 1.2−2009. — Note the manufacturer’s database.

Data on standard

1 DEVELOPED by the Technical Committee for standardization TC 368 «Copper"

2 SUBMITTED by the Technical Secretariat of the Interstate Council for standardization, Metrology and certification

3 ACCEPTED by the Interstate Council for standardization, Metrology and certification (minutes N 35 dated June 11, 2009)

The standard was accepted by voting:

4 this standard takes into account the basic regulatory provisions of the following international standards:

— ISO 5956:1984 «Copper and copper alloys. Determination of antimony. Spectrometric method with rhodamine B» (ISO 5956:1984 «Copper and copper alloys — Determination of antimony content — Rhodamine In spectrometric method», NEQ);

— ISO 5959:1984 «Copper and copper alloys. Determination of bismuth. Spectrometric method using diethyldithiocarbamate» (ISO 5959:1984 «Copper and copper alloys — Determination of bismuth content — Diethyldithiocarbamate spectrometric method», NEQ)

5 by Order of the Federal Agency for technical regulation and Metrology dated September 10, 2009 N 322-St inter-state standard GOST 31382−2009 introduced as a national standard of the Russian Federation from April 1, 2010

6 REPLACE GOST 13938.1−78 — GOST 13938.10−78, GOST 13938.12−78, GOST 13938.15−88, GOST 9717.1−82, GOST 27981.0−88, GOST 27981.3−88, GOST 27981.4−88


Information about introduction in action (termination) of this standard is published in the index «National standards».

Information about the amendments to this standard is published in the index «National standards», and the text changes — in the information sign «National standards». In case of revision or cancellation of this standard the appropriate information will be published in the information index «National standards»

1 Scope

This standard applies to copper according to the GOST 859 and establishes General requirements for methods of analysis/measurement of copper, security requirements in the analysis/measurement methods of performance analysis/measurements of the mass fraction of copper and impurities in it.

2 Normative references

This standard uses the regulatory references to the following international standards:

GOST 8.315−97 State system for ensuring the uniformity of measurements. Standard samples of composition and properties of substances and materials. The main provisions of the

GOST 12.0.004−90 System of standards of occupational safety. Organization of training safety. General provisions

GOST 12.1.004−91 System safety standards. Fire safety. General requirements

GOST 12.1.005−88 standards System of labor safety. General hygiene requirements for working zone air

GOST 12.1.007−76 System of standards of occupational safety. Harmful substances. Classification and General safety requirements

GOST 12.1.010−76 System of standards of occupational safety. No danger of explosion. General requirements

GOST 12.1.016−79 System of standards of occupational safety. The air of the working area. Requirements for measurement techniques of concentrations of harmful substances

GOST 12.1.030−81 System of standards of occupational safety. Electrical safety. Protective grounding, neutral earthing

GOST 12.2.007.0−75 System safety standards. Products electrical. General safety requirements

12.4.009 GOST-83 System of standards of occupational safety. Fire fighting equipment for protection of objects. Principal. The accommodation and service

GOST 12.4.021−75 System safety standards. System ventilation. General requirements

GOST 61−75 Reagents. The acetic acid. Specifications

GOST 83−79 Reagents. Sodium carbonate. Specifications

GOST 123−2008 Cobalt. Specifications

GOST 193−79 (ISO 431−81) copper Ingots. Specifications

GOST 199−78 Reagents. Sodium acetate 3-water. Specifications

GOST 200−76 Reagents. Sodium posterolaterally 1-water. Specifications

GOST 334−73 Paper scale-coordinate. Specifications

GOST 546−2001 copper Cathodes. Specifications

GOST 804−93 primary Magnesium ingots. Specifications

GOST 849−2008 Nickel primary. Specifications

GOST 859−2001 Copper. Brand

GOST 860−75 Tin. Specifications

GOST 1089−82 Antimony. Specifications

GOST 1277−75 Reagents. The silver nitrate. Specifications

GOST 1467−93 Cadmium. Specifications

GOST 1770−74 (ISO 1042−83, ISO 4788−80) Glassware volumetric laboratory glass. Cylinders, beakers, flasks, test tubes. General specifications

GOST 2062−77 Reagents. Acid bromide and hydrogen. Specifications

GOST 3117−78 Reagents. Ammonium acetate. Specifications

GOST 3118−77 Reagents. Hydrochloric acid. Specifications

GOST 3640−94 Zinc. Specifications

GOST 3652−69 Reagents. Citric acid monohydrate and anhydrous. Specifications

GOST 3760−79 Reagents. The aqueous ammonia. Specifications

GOST 3765−78 Reagents. Ammonium molybdate. Specifications

GOST 3773−72 Reagents. The ammonium chloride. Specifications

GOST 3778−98 Lead. Specifications

GOST 4109−79 Reagents. Brom. Specifications

GOST 4147−74 Reagents. Iron (III) chloride 6-water. Specifications

GOST 4159−79 Reagents. Iodine. Specifications

GOST 4165−78 Reagents. Copper (II) sulfate 5-water. Specifications

GOST 4166−76 Reagents. The sodium sulfate. Specifications

GOST 4198−75 Reagents. Potassium phosphate odnosemjannyj. Specifications

GOST 4201−79 Reagents. Sodium carbonate acidic. Specifications

GOST 4204−77 Reagents. Sulphuric acid. Specifications

GOST 4208−72 Reagents. Salt of protoxide of iron and ammonium double sulfate (salt Mora). Specifications

GOST 4212−76 Reagents. Preparation of solutions for colorimetric and nephelometric analysis

GOST 4220−75 Reagents. Potassium dichromate. Specifications

GOST 4232−74 Reagents. The potassium iodide. Specifications

GOST 4233−77 Reagents. Sodium chloride. Specifications

GOST 4236−77 Reagents. Lead (II) nitrate. Specifications

GOST 4328−77 Reagents. Sodium hydroxide. Specifications

GOST 4329−77 Reagents. Aljumokalievyh alum. Specifications

GOST 4459−75 Reagents. Potassium chronologicly. Specifications

GOST 4461−77 Reagents. Nitric acid. Specifications

GOST 4465−74 Reagents. Nickel (II) sulphate 7-aqueous. Specifications

GOST 4478−78 Reagents. Sulfosalicylic acid 2-water. Specifications

GOST 4517−87 Reagents. Methods for the preparation of accessory reagents and solutions used in the analysis

GOST 4520−78 Reagents. Mercury (II) nitrate 1-water. Specifications

GOST 4960−2009 copper Powder electrolytic. Specifications

GOST 5456−79 Reagents. Of hydroxylamine hydrochloride. Specifications

GOST 5457−75 Acetylene, dissolved and gaseous. Specifications

GOST 5556−81 Wool medical hygroscopic. Specifications

GOST 5583−78 (ISO 2046−73) Oxygen gas technical and medical. Specifications

GOST 5644−75 sodium Sulfite anhydrous. Specifications

GOST 5789−78 Reagents. Toluene. Specifications

GOST 5817−77 Reagents. Acid wine. Specifications

GOST 5828−77 Reagents. Dimethylglyoxime. Specifications

GOST 5845−79 Reagents. Potassium-sodium vinocity 4-water. Specifications

GOST 5905−2004 (ISO 10387:1994) metal Chrome. Technical requirements and delivery conditions

GOST 6008−90 metallic Manganese and nitrated manganese. Specifications

GOST 6344−73 Reagents. Thiourea. Specifications

GOST 6563−75 technical articles made of noble metals and alloys. Specifications

GOST 6709−72 distilled Water. Specifications

GOST 6836−2002 Silver and alloys on its basis. Brand

GOST 8655−75 red Phosphorus technical. Specifications

GOST 8677−76 Reagents. Of calcium oxide. Specifications

GOST 8864−71 Reagents. Sodium N, N-diethyldithiocarbamate 3-water. Specifications

GOST 9147−80 Glassware and equipment lab porcelain. Specifications

GOST 9336−75 Reagents. Ammonium meta undeviatingly. Specifications

GOST 9849−86 iron Powder. Specifications

GOST 10157−79 Argon gaseous and liquid. Specifications

GOST 10163−76 Reagents. Starch soluble. Specifications

GOST 10298−79 Selenium technical. Specifications

GOST 10652−73 Reagents. Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid, 2-water (Trilon B). Specifications

GOST 10727−91 Yarn and fiber glass unidirectional. Specifications

GOST 10928−90 Bismuth. Specifications

GOST 10929−76 Reagents. Hydrogen peroxide. Specifications

GOST 11069−2001 primary Aluminium. Brand

GOST 11125−84 nitric Acid of high purity. Specifications

GOST 11293−89 Gelatin. Specifications

GOST 11773−76 Reagents. Sodium phosphate disodium. Specifications

GOST 12026−76 laboratory filter Paper. Specifications

GOST 14261−77 hydrochloric Acid of high purity. Specifications

GOST 14262−78 sulphuric Acid of high purity. Specifications

GOST 17022−81 Graphite. Types, marks and General technical requirements

GOST 18300−87 ethyl rectified technical. Specifications

GOST 19908−90 Crucibles, bowls, beakers, flasks, funnels, test tubes and caps made of transparent quartz glass. General specifications

GOST 20015−88 Chloroform. Specifications

GOST 20288−74 Reagents. The carbon tetrachloride. Specifications

GOST 20298−74 ion-exchange Resins. Cation exchange resins. Specifications

GOST 20301−74 ion-exchange Resins. The anion exchange resin. Specifications

GOST 20448−90 liquefied hydrocarbon Gases fuel for household consumption. Specifications

GOST 20478−75 Reagents. Ammonium neccersarily. Specifications

GOST 20490−75 Reagents. Potassium permanganate. Specifications

GOST 21241−89 Tweezers medical. General technical requirements and test methods

GOST 22180−76 Reagents. Oxalic acid. Specifications

GOST 22861−93 Lead of high purity. Specifications

GOST 22867−77 Reagents. The ammonium nitrate. Specifications

GOST 24104−2001* laboratory Scales. General technical requirements
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* On the territory of the Russian Federation GOST R 53228−2008, here and hereafter. — Note the manufacturer’s database.

GOST 24231−80 non-ferrous metals and alloys. General requirements to selection and preparation of samples for chemical analysis

GOST 24363−80 Reagents. Potassium hydroxide. Specifications

GOST 25086−87 non-ferrous metals and their alloys. General requirements for methods of analysis

GOST 25336−82 Glassware and equipment laboratory glass. The types, basic parameters and dimensions

GOST 25644−96 detergents, synthetic powder. General technical requirements

GOST 25794.1−83 Reagents. Methods for the preparation of titrated solutions for acid-base titration

GOST 27025−86 Reagents. General instructions for testing

GOST 27067−86 Reagents. Ammonium radamisty. Specifications

GOST 27068−86 Reagents. Chernovetskiy sodium (sodium thiosulfate) 5-water. Specifications

GOST 29169−91 (ISO 648−77) oils. Pipette with one mark

GOST 29227−91 (ISO 835−1-81) oils. Pipettes are graduated. Part 1. General requirements

GOST 29251−91 (ISO 385−1-84) oils. Burette. Part 1. General requirements

ST SEV 543−77 Number. Record rules and rounding

Note — When using this standard appropriate to test the effect of reference standards for the sign «National standards» drawn up as of January 1 of the current year and related information signs, published in the current year. If the reference standard is replaced (changed), when using this standard should be guided by replacing (amended) standard. If the reference standard is cancelled without replacement, then the situation in which the given link applies to the extent that does not affect this link.

3 General requirements

3.1 General requirements for methods of analysis/measurement — GOST 25086.

3.2 General requirements for measurement means, auxiliary devices, materials, reagents, solutions — according to GOST 25086.

3.3 Preparation of solutions of chemical reagents in accordance with GOST 4212, 4517 GOST, GOST and GOST 25794.1 27025.

3.4 allowed the use of other measurement means, auxiliary devices, materials, reagents, providing the analysis/measurements with an established accuracy.

3.5 Selection and preparation of samples of copper to the analysis/measurement shall be carried out according to GOST 193, 546 or GOST GOST 24231.

3.6 weighing laboratory scales are used according to GOST 24104. In the method of analysis/measurement must be specified accuracy class of weights.

3.7 Mass fraction of copper is determined in parallel in three batches, impurities via the number of parallel measurements, the number of which is specified in a particular method of analysis/measurement, but at least two. Along with the analysis/measurement in the same conditions conduct control experience for the amendment of the results of the analysis/measurements. In the determination of copper is carried out two test experience. In the determination of impurities the number of parallel definitions in a control experiment it should correspond to the number of parallel definitions specified in the method of analysis/measurement.

3.8 For the calcination and fusion used laboratory muffle furnace providing heating up to a temperature of 1000 °C. To dry the used laboratory drying oven providing temperatures up to 250 °C. For dissolution and evaporation of solutions used the electric oven with closed coil that provides heating to a temperature of 350 °C.

3.9 To measure time intervals less than 5 min used hourglasses and stopwatches, 5 min, timers or clocks of any type.

3.10 Terms relating to the degree of heating of water (solution) and the duration of the operations — according to GOST 27025.

3.11 For the preparation of solutions of known mass concentration of the used metals and their compounds with a mass fraction of main component not less than 99.9% if the measurement procedure does not provide otherwise. Method of mortar preparation — according to GOST 4212 or by the present standard.

3.12 Weighing of the analyte, the substance for the preparation of solutions of known metal concentration and precipitation in gravimetric analysis is carried out, unless otherwise stipulated in the method of analysis in the balance of special accuracy class according to GOST 24104.

3.13 Checking the admissibility of the results of the analysis/measurements and the establishment of the final result in accordance with the standards [1], [2].

3.14 Control of accuracy of analysis results/measurements

Control of accuracy of analysis results/measurements carried out in accordance with the recommendations of [3]:

a) comparing the result of control procedures with standard control. The result of the control procedure, is calculated by the formula

, (1)

where the result of the analysis/measurement of a standard sample (CO);

 — certified value.

The ratio control is calculated by the formula

, (2)

where is the value characteristics error of the result of the analysis/measurement when implemented in a particular laboratory, the corresponding certified value.

If during the inspection, use WITH that have not been used in establishing the accuracy rate of the results of analysis/measurement, and in case of exceeding the error WITH one third of the error of methods of analysis/measurement, ratio control precision is calculated by the formula

, (3)

where  — characteristic error of the certified value of the measured element.

b) using the composition adopted in accordance with GOST 8.315. The frequency measuring part in accordance with the guidelines for quality assurance of analytical work force at the enterprise.

Mass fraction of the designated component in WITH find by parallel measurements established by a particular method of analysis/measurement.

To control the stability of the results of analysis/measurement, it is recommended to use a control card (CC) Shewhart standards [2] (section 6) and [4].

Algorithms for the estimation of the stability of the results of the analysis/measurement — in accordance with the guidelines for ensuring the quality of analytical work applicable to the company, subject to the requirements of the standard [2] (section 6).

In the absence WITH allowed control of accuracy of analysis results/measurements according to GOST 25086 using the method of additives certified mixtures or for recommendations [5].

3.15 the results of the analysis/measurement

The results of the analysis/measurements are in the form of (at confidence probability of 0.95),

where the result of analysis/measurement, %;

 — accuracy of results of analysis/measurement %.

The values given in a particular method of analysis/measurement.

Note — In the case when the final result of the analysis/measurements take the median, the results are presented without specifying the limits of error.

3.16 permitted the construction of calibration graphs and calculating results of analysis/measurement to be carried out using software of measuring instruments. In this case, the software must be certified.

3.17 the Rounding of the results of analysis/measurement is carried out in accordance with the requirements of ST CMEA 543.

4 safety Requirements

4.1 Preparation of samples for analysis and the analysis (dissolution in acids, alkalis etc.) and all the operations of chemical analysis related to the release of toxic fumes or gases should be performed in fume cupboards or boxes equipped with local suction device according to GOST 12.4.021.

4.2 Laboratory facilities should be equipped with ventilation systems according to GOST 12.4.021.

4.3 When performing analysis of copper in the workplace air can be harmful substances maximum allowable concentration (Mac) of them in the air of working zone should correspond to GOST 12.1.005 and hygienic standards [6].

4.4 Monitoring of content of harmful substances in the air of working zone should be carried out in accordance with the requirements of GOST 12.1.005, GOST 12.1.007 and GOST 12.1.016.

4.5 Laboratory space, in which the work is performed according to the chemical analysis of the investigated material must meet fire safety requirements according to GOST 12.1.004 and fire safety rules [7]. The means and methods of fire suppression should be applied according to the GOST 12.4.009 depending on the origin and nature of the fire.

4.6 When working with flammable and explosive gases should comply with GOST 12.1.010, GOST 12.1.004. When using gas cylinders should comply with the requirements of regulation [8].

4.7 Electrical instrumentation and laboratory equipment and their use must comply with the requirements of GOST 12.2.007.0, GOST 12.1.030 and standard [9]. Grounding shall conform to the requirements of regulation [10].

4.8 Organization of safety training and knowledge testing of operating safety requirements of work — according to GOST 12.0.004.

4.9 laboratory Personnel must be provided with special clothing, special footwear and other individual protection means in accordance with the rules [11].

4.10 laboratory Personnel must be provided with household premises in the group production processes IlIa in accordance with construction norms and rules [12].

5 Methods of determining the mass fraction of copper

5.1 Scope

This section is set electrogravimetry and calculated methods of determining the mass fraction of copper.

5.2 Requirements on error analysis

The error analysis results (for the mass concentration of copper of 99.00% and above) for a confidence probability of 0.95, should not exceed ±0,10%.

5.3 measurement Means, auxiliary devices, materials, solutions

When you perform analysis used the following measuring instruments, auxiliary devices:

electrodes made of platinum mesh according to GOST 6563;

installation for electrolysis with ammeter, voltmeter, rheostat, providing carrying out the electrolysis while stirring at a current density of 2 to 3 A/DMand voltage from 2.2 to 2.5;

— a photoelectric photometer or spectrophotometer with all accessories;

— spectrophotometer, atomic absorption, comprising a radiation source for copper, the burner for flame acetylene-air and the spray system;

— air compressor;

centrifuge with all accessories;

— drying oven with thermostatic control;

— special laboratory scales of accuracy class according to GOST 24104;

pipettes not lower than 2nd accuracy class according to GOST and GOST 29169 29227;

— glasses-1−50 TCS-1−100 TCS-1−250 TC GOST 25336;

— volumetric flasks 2−25−2, 2−100−2, 2−200−2, 2−250−2, 2−1000−2 according GOST 1770;

— funnel VD-1−100 TC GOST 25336;

— dryer 2−190 according to GOST 25336.

When you perform analysis used the following materials, solutions:

— acetylene according to GOST 5457;

— nitric acid according to GOST 4461;

— sulfuric acid according to GOST 4204, and diluted 1:1;

— ammonium nitrate according to GOST 22867;

— mix to dissolve;

— citric acid according to GOST 3652;

— ammonia water according to GOST 3760, diluted 1:4;

— salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid, dvuvodny (Trilon B) according to GOST 10652, 0.1 M solution;

— cuprizone, bis-(cyclohexanone) oxalidaceae, solution mass concentration of 2.5 g/DM;

sodium sulphate anhydrous according to GOST 4166;

— phenolphthalein (indicator) [13], an alcoholic solution of the mass concentration of 1 g/DM;

— carbon tetrachloride according to GOST 20288;

— rectified ethyl alcohol according to GOST 18300;

— copper according to the GOST 859;

— copper solutions of known concentration;

— indicator paper universal technical conditions [14];

— chloroform according to GOST 20015;

— diethyldithiocarbamate, lead (II) by [15], the solution of the mass concentration of 0.2 g/lin chloroform.

5.4 Method of analysis

The method is based on the electrolytic release of copper from a solution of sulfuric and nitric acids in the presence of ammonium salts at a platinum mesh electrode at a current density of 2 to 3 A/DMand voltage from 2.2 to 2.5 V.

The copper remaining in the electrolyte is determined by atomic absorption or photometric method. In case of disagreement in the assessment of mass fraction of copper using photometric method based on formation of colored complex compounds of copper with cuprizone or diethyldithiocarbamate lead.

When the mass fraction of copper from 99.00% to 99,90% of copper in the amount of silver is determined electrolytically.

Mass fraction of copper of more than 99,90% is determined by difference, subtracting the amount of certain impurities from 100%.

5.5 Preparation for analysis

5.5.1 When preparing a mixture for dissolving a portion of 500 g of ammonium nitrate dissolved in 500 cmof water is added to 500 cmof nitric acid, 200 cmof sulphuric acid and add water to 2000 cm.

5.5.2 in preparing the solution of ammonium citrate is weighed 150 g of citric acid dissolved in 400 cmof water, add 200 cmof solution of ammonia, cooled and made up to 1000 cmwater, and stirred.

5.5.3 When preparing a 0.1 M solution of Trilon B weighed 37.2 g Trilon B dissolved in 800 cmof water, top up with water to 1000 cmand mixed well.

5.5.4 When diluting cuprizone mass concentration of 2.5 g/DMweighed 2.5 g cuprizone dissolved with stirring in 900 cmof water at a temperature of from 70 °C to 80 °C. After cooling, the solution was filtered into a vessel made of dark glass, top up with water to 1000 cm, mixed and stored in this vessel. The solution to fit the application within 10 days.

5.5.5 For constructing the calibration graphs prepare solutions of known copper concentration.

In preparing the solution And the mass concentration of copper of 0.5 mg/cmthe weight 0,5000 g of copper is dissolved in 20 cmof the mixture to dissolve, and when heated removes the oxides of nitrogen. The solution was cooled, diluted with water to 100 cmand placed in a measuring flask with volume capacity of 1000 cm, made up to the mark with water and mix.

In the preparation of a solution of mass concentration of copper of 0.01 mg/cm20 cmsolution And placed in a measuring flask with volume capacity of 1000 cm, add 5 cmof sulphuric acid diluted 1:1, made up to 1000 cmwater, and stirred.

5.5.6 For preparation of a solution of lead diethyldithiocarbamate (II) the mass concentration of 0.2 g/lin chloroform weighed 0.2 g of diethyldithiocarbamate, lead (II) was placed in a measuring flask with volume capacity of 1000 cm, add 100 to 200 cmof chloroform, and stirred to dissolve the sample, made up to the mark with chloroform and mix again. The solution was stored in a flask made of dark glass in a dark place.

5.5.7 the Construction of calibration graphs

5.5.7.1 Construction of calibration curve when using photometric method for the determination of copper in electrolyte cuprizone

Select 0; 2,0; 4,0; 6,0; 8,0 and 10,0 cmof solution B and placed in a volumetric flask with a capacity of 100 cmeach, which corresponds to 0; 20; 40; 60; 80 and 100 micrograms of copper. Add 4 cmof the mixture for dissolution, 50 cmwater, 10 cmof ammonium citrate solution, 2 drops of phenolphthalein solution, ammonia solution, diluted 1:4 until a slightly pink color and 1 cmexcess, 10 cmcuprizone solution, made up to the mark with water and mix. The pH of the solution should be between 8.5 and 9.0.

Measurement of optical density is carried out as specified in 5.6.3.

On the found values of optical density and corresponding values of copper content to build a calibration curve.

5.5.7.2 Construction of calibration curve when using photometric method for the determination of copper in electrolyte of lead diethyldithiocarbamate

Six separatory funnels with a capacity of 100 cmeach placed 0; 0,5; 1,0; 2,0; 3,0 and 5,0 cmof solution B, which corresponds to 0; 5; 10; 20; 30 and 50 micrograms of copper. Pour water up to 50 cmand further analysis is carried out according to 5.6.4.

Extraction and measurement of the optical density of the solution is carried out as specified in 5.6.4.

On the found values of optical density and corresponding values of copper content to build a calibration curve.

5.5.7.3 Construction of calibration curve when using an atomic absorption method for the determination of copper in the electrolyte

In a volumetric flask with a capacity of 100 cmeach select 0; 5,0; 10,0; 15,0 and 20.0 cmof a solution, made up to the mark with water and mix. Solutions contain 0; 0,5; 1,0; 1,5 and 2,0 µg/cmof copper. The solutions were sprayed into the flame and measure the absorbance in the flame at a wavelength of 324,7 nm.

On the found values of optical density and corresponding values of copper content to build a calibration curve.

5.6 Performing analysis

5.6.1 General requirements for methods of analysis and security requirements for performing work in accordance with sections 3 and 4.

5.6.2 Electrogravimetry method for the determination of copper (at a mass fraction of from 99.00% to 99,90%)

A sample of copper weighing from 1,0000 to 2,0000 g placed on the weighing pan, where it is weighed platinum cathode, designed for electrolysis, and determine the total mass of the cathode and copper. Allows for separate weighing of the sample of copper and a cathode, intended for electrolysis. A sample of copper is transferred to a beaker with a capacity of 250 cm, 40 cm, addthe mixture to dissolve and the glass cover watch glass. After dissolution of sample of copper the solution is gently heated to remove oxides of nitrogen, diluted to 180 cmof water, heated to 40 °C and into the solution immerse the platinum electrodes. This is followed by electrolysis for 2.5 hours while stirring the solution at a current density of 2 to 3 A/DMand voltage from 2.2 to 2.5 V. To check the completeness of separation of copper electrodes immersed 5 mm below the original position and continue the electrolysis. In the absence of plaque copper on svezheokrashennoj portion of the cathode electrolysis is complete.

Then, without turning off the current, the platinum electrode was washed with water and then turning off the current, washed with ethanol (10 cmof alcohol per one definition).

The cathode with the separated copper is dried at a temperature of from 100 °C to 105 °C for 5 min, cooled in a desiccator and weighed on the scales on which was weighed the cathode, and a charge of copper before analysis.

The electrolyte washings (following washing of the platinum cathodes) is poured into a measuring flask with a capacity of 200 to 250 cm, made up to the mark with water and mix. Retain electrolyte for the determination of Nickel.

The copper remaining in the electrolyte after the electrolysis, is determined in the form coloured compounds with cuprizone or lead diethyldithiocarbamate photometric method as described in 5.6.3 and 5.6.4, or atomic absorption method in accordance with 5.6.5.

5.6.3 Photometric method for the determination of copper in electrolyte cuprizone

Pipette take 50 cmof the electrolyte solution and placed in a volumetric flask with a capacity of 100 cm, add 10 cmof ammonium citrate solution, 2 drops of solution of phenolphthalein and ammonia solution, diluted 1:4, to obtain a slightly pink color. Then add 1 cmof ammonia solution diluted 1:4, 10 cmcuprizone, made up to the mark with water and mix.

The pH of the solution should be between 8.5 and 9.0, the pH of the test solution on the indicator paper.

Optical density of the solution measured after 5 to 30 min at a wavelength of 600 nm in a cuvette with the thickness of the light absorbing layer 30 mm. with a Solution of comparison in the measurement of optical density is water. At the same time carried out two test experience with all the applied reagents. The average value of optical density in the reference experiment is subtracted from the value of the optical density of the analyzed solution.

Mass of copper set on a calibration schedule, constructed as specified in 5.5.7.1.

5.6.4 Photometric method for the determination of copper in electrolyte of lead diethyldithiocarbamate

Select aliquot part of the electrolyte solution from 5 to 10 cmand placed in a beaker with a capacity of 50 cm, pour 5 cmof sulphuric acid, diluted 1:10, and evaporated to release vapors of sulfuric acid.

The solution was cooled, poured 10 to 20 cmof water was placed in a separating funnel with a capacity of 100 cmand dilute with water to volume of 50 cm. Add 10 cmof a solution of lead diethyldithiocarbamate and extracted within 2 min. After separation of layers, extract decanted into a volumetric flask with a capacity of 25 cm(where previously placed 1 g of anhydrous sodium sulfate).

The extraction was repeated with 10 cmof the extractant. The organic layer is decanted into the same volumetric flask, dilute to the mark with chloroform and mix.

Optical density of the solution is measured at a wavelength of 413 nm in a cuvette with the thickness of the light absorbing layer 50 mm. Solution comparison with the optical density measurement is carbon tetrachloride.

At the same time carried out two test experience. This is placed in a separatory funnel 4 cmof the mixture to dissolve, top up to 50 cmof water and then do as above. The average value of optical density in the reference experiment is subtracted from the value of the optical density of the analyzed solution.

Mass of copper set on a calibration schedule, constructed as specified in 5.5.7.2.

5.6.5 Atomic absorption method for the determination of copper in the electrolyte

Part of the electrolyte solution is placed in a beaker with a capacity of 100 cm, previously it was washed with this solution. The solution is sprayed into the flame and measure the absorbance in the flame at a wavelength of 324,7 nm.

Mass of copper in the solution set for the calibration graphics constructed as described in 5.5.7.3.

5.7 Processing of analysis results

5.7.1 Mass fraction of copper , %, when using electrogravitational and photometric methods of determination are calculated according to the formula

. (4)

Mass fraction of copper , %, when using electrogravitational and atomic absorption methods for the determination of copper is calculated by the formula

, (5)

where is the mass of the cathode with the deposited copper, g;

 — the mass of cathode, g;

 — the mass of copper was found in the calibration schedule, mcg;

 — the mass of copper was found in the calibration schedule, µg/cm;

 — analyze the volume of the electrolyte, cm;

 — volume aliquote part of the electrolyte, cm;

 — weight of copper,

5.7.2 For the result of the analysis taking the arithmetic mean value of three parallel measurements, provided that the difference between the highest and the lowest results in terms of repeatability with a confidence level of 0.95 does not exceed 0,06%.

If the difference between the highest and lowest results of parallel measurements exceeds the limit value of the frequency of occurrence, perform the procedure described in the standard [2] (paragraph 5.2.2.1).

The absolute value allowable discrepancies between the two analysis results obtained in different laboratories, should not exceed the limit of reproducibility of 0.14% for a confidence probability of 0.95.

5.7.3 Determination of copper (at a mass fraction of its more than 99,90%)

5.7.3.1 Mass fraction of copper , %, calculated by difference between 100 and the sum of all the designated impurities by the formula

, (6)

where , , ,…  — average mass fraction of copper in certain impurities, %.

The number of significant digits depends on the original requirements, set in normative document on a specific type of product.

5.7.3.2 discrepancy between the results of two parallel definitions/measurements of impurities in copper must not exceed the limits of repeatability are given in the respective methods for the determination of a particular impurity.

Discrepancies between the results of the analysis/measurement of impurities in of copper obtained in different laboratories, should not exceed the limits of reproducibility given in the appropriate methods for the determination of a particular impurity.

6 Methods of determination of sulphur mass fraction

6.1 Scope

This section established titrimetric method (with mass fraction of sulfur from 0,0010% to 0.020%) and the method of infrared spectrometry (at the mass fraction of sulfur from 0,0002% to 0.050%) determine the mass fraction of sulfur in copper.

6.2 Requirements for uncertainty analysis

Error of results of analysis/measurement of the mass fraction of sulphur limit values of repeatability and reproducibility for a confidence probability of 0.95 shall be as given in tables 1, 2 and 3.


Table 1 — Titrimetric method

Percentage

Table 2 — Method of infrared spectrometry in the presence of flux

Percentage

Table 3 — Method by infrared spectrometry without the use of flux

Percentage

6.3 Titrimetric method

6.3.1 measurement Means, auxiliary devices, materials, solutions

When you perform analysis used the following measuring instruments, auxiliary devices:

— special laboratory scales of accuracy class according to GOST 24104;

— volumetric flasks 2−25−2; 2−250−2; 2−1000−2 according GOST 1770;

pipettes not lower than 2nd accuracy class according to GOST 29227;

— burette 1−1-2−25−0,1 according to GOST 29251;

— beakers 50, 100 GOST 1770;

— flasks KN-2−250−34 TCS GOST 25336;

— glasses-1−100 TCS according to GOST 25336;

oven muffle with heating temperature up to 1050 °C;

installation for the determination of sulfur according to figure 1;

oven with tubular silicafume heaters that provide heating to 1250 °C;

— a millivoltmeter or a potentiometer of any type;

— porcelain single-channel tube (outer diameter — 26 mm, internal diameter 21 mm, length from 850 to 900 mm);

pumps porcelain ЛС2 according to GOST 9147;

— dryer 2−190 according to GOST 25336 filled with calcium oxide, pre-calcined at a temperature of from 970 °C to 1050 °C, or calcium chloride.

Figure 1 — Installation for determination of sulfur

1 — oxygen cylinder equipped with pressure-reducing valve for regulating the rate of supply of oxygen in the furnace; 2 — washing flask containing a solution of potassium permanganate in a solution of potassium hydroxide or sodium hydroxide; 3 — bottle, containing in the lower part of fused calcium chloride and a layer of glass or ordinary wool, and in the upper part of the potassium hydroxide or sodium hydroxide; 4 — crane, enabling to regulate the flow of purified oxygen into the tubes for combustion; 5 — tubular furnace with silicafume heaters that provide heating to 1250 °C; 6 — thermocouple; 7 — millivoltmeter or potentiometer of any type; 8 — tube for oxygen combustion; 9 — boat for the combustion of samples; 10 — cleansing the vessel with a quartz wool; 11 — tap in front of the absorption vessel; 12 — absorption vessel, consisting of two identical vessels are connected by glass bridges. Allowed the use of two glass cylinders with a height of 250 mm from the glass the same color (figure 2); 13 — burette for titration

Figure 1 — Installation for determination of sulfur

Figure 2 — Absorption vessel

Figure 2 — Absorption vessel

When you perform analysis used the following materials, solutions:

— potassium dichromate according to GOST 4220, recrystallized twice and dried at 170 °C, a solution of 0.025 n;

— potassium iodide according to GOST 4232, solution mass concentration of 50 g/DM;

— potassium hydroxide (potassium hydroxide) according to GOST 24363, solution mass concentration of 400 g/DM;

— sodium hydroxide (sodium hydroxide) according to GOST 4328, solution mass concentration of 400 g/DM;

— potassium permanganate according to GOST 20490, solution mass concentration 40 g/lsolution of potassium hydroxide or sodium hydroxide;

— calcium chloride [16], melted;

— sulfuric acid according to GOST 4204, diluted 5:100;

— soluble starch according to GOST 10163, solution mass concentration 10 g/DM;

the anhydrous sodium carbonate according to GOST 83;

sodium Chernovetskiy according to GOST 27068, a solution of 0.025 n;

— iodine according to GOST 4159, solution of 0.001 n;

— calcium oxide according to GOST 8677;

standard sample copper, steel (non-alloy) or iron with a mass fraction of sulfur from 0.002% to 0.03%.

6.3.2 analysis Method

The method is based on the combustion of a sample of copper containing sulphur in a current of oxygen at a temperature of 1200 °C, the absorption of the formed sulphur dioxide with water and the titration of sulphurous acid solution of iodine in presence of starch.

6.3.3 Preparation for analysis

6.3.3.1 Before testing, check tightness of installation for the determination of sulfur (figure 1) and the correctness of its Assembly.

To do this, connect the whole setup with a balloon containing oxygen, open the three-way stopcock to the air, carefully open the cylinder valve, allow oxygen at a speed of 20−30 bubbles per minute, switch the three-way valve to the position at which oxygen enters the furnace, and close the valve in front of the absorption vessel. In 2−3 min it should stop bubbling in the wash bottles, and then must wait another 5 to 7 min. If the bubbles are no longer selected, the system can be considered sealed.

6.3.3.2 Before analysis it is necessary to check at the temperature from 1200 °C to 1250 °C, the device for combustion for tightness and the presence of volatile reducing substances. To do this in both vessels the absorption of the device is poured on 50 cmwater and 10 cmstarch solution, poured from the burette a few drops of iodine solution to the appearance of the blue color (intensity of color in both the vessels should be the same). Heat the oven to a temperature of from 1100 °C to 1250 °C and oxygen is passed at a speed of 40−50 bubbles per minute.

If after 4−5 min, the color of the solution in the left vessel disappears, this means that stand out from the tube reducing agents that react with iodine. In this case, without interrupting the current of oxygen to the solution in the left vessel poured a few drops of iodine solution and continue the addition of iodine solution until a blue coloration in the solution will remain constant and the same intensity with the color of the solution in the right container.

6.3.3.3 For analysis porcelain boats pre-calcined at a temperature of from 850 °C to 900 °C for 1 h. Calcined pumps placed in a desiccator. Before analysis the boat is calcined at a temperature of 1200 °C in an oxygen atmosphere, a check on the sulphur content in the course of the analysis. Suspension with the test sample placed in a proven boat. After the test the boat was no longer used.

6.3.3.4 in the preparation of 0.025 n solution servational sodium (sodium thiosulfate) suspension of 6.2 g dissolved in 100 cmsvejeprokipachenna and cooled water, add 0.2 g of anhydrous sodium carbonate, add water to 1000 cmand mixed well.

The mass concentration of a solution of sodium servational set for 2−3 days after preparation of the solution.

When establishing the mass concentration of 0.025 n solution of sodium servational 10 cmof sulphuric acid diluted 5:100, placed in a conical flask with a capacity of 250 cm, flow 10 cmof a solution of potassium iodide, 25 cmof 0.025 n solution of potassium dichromate. Close the flask with ground stopper and leave in a dark place for 8−10 mins Pour water to a volume of 70 to 80 cmand titrate the liberated iodine with a solution of sodium servational to light yellow in color, pour 2 cm ofstarch solution and continue titration until the disappearance of blue color.

The mass concentration of the solution servational sodium , g/cm, is calculated by the formula

, (7)

where  — volume of the solution servational sodium, spent on titration, sm.

6.3.3.5 in the preparation of 0.001 n solution of iodine suspension to 0.127 g of iodine dissolved in 50 cmof a solution of potassium iodide and dilute the solution with water up to 1 DM. Solution store in a glass container of dark glass.

The titer of the iodine solution, expressed in grams of sulfur, set in four batches a standard sample with known sulfur content. Burning sulfur in this case is carried out according to 6.3.4.

The titer of a solution of iodine sulphur , g, is calculated by the formula

, (8)

where  — mass fraction of sulfur in the standard sample, %;

 — weight of standard sample, g;

 — the volume of iodine solution consumed for titration, sm.

Note — in the absence of standard sample mass concentration of iodine solution are placed on the solution servational sodium mass concentration which is installed in the solution of potassium dichromate.


When establishing the mass concentration of 0.001 n iodine solution is prepared 0,001 n solution of sodium servational with the dilution of 0.025 n solution: pipetted 10 cmof 0.025 n solution of sodium chernovetskogo, placed in a volumetric flask with a capacity of 250 cm, add pre-boiled and chilled water to the mark and mix. The solution is prepared the day of application. In a flask with a capacity of 250 cmpour 18 to 20 cmof water, poured from the burette accurately measured 20 cmof iodine solution, dilute with water to volume from 70 to 80 cm, mixed and titrated with a solution of 0.001 n sodium chernovetskogo to light yellow color, then pour 2 cm ofstarch solution and continue titration until the disappearance of blue color.

The mass concentration of iodine solution , g/cm, is calculated by the formula

, (9)

where is the mass concentration of the solution servational sodium equal to /25, g/cm;

the volume of the solution servational sodium, spent on titration, sm.

The titer of a solution of iodine sulphur , g, is calculated by the formula

. (10)

6.3.4 Performing analysis

6.3.4.1 General requirements for methods of analysis and safety requirements when performing analyses in accordance with sections 3 and 4.

6.3.4.2 Mass fraction of sulfur is determined simultaneously from the two batches of samples.

6.3.4.3 Simultaneously through all stages of sample preparation to the analysis carried out control and experience on the purity of the reagents.

6.3.4.4 a sample of copper with a mass of 2.0 g (at a mass fraction of sulfur up to 0.005%) by weight or 1.0 g (for the mass concentration of sulfur in excess of 0.005%) distributed evenly along the bottom of a preheated boats for burning.

Then in a tube furnace (in the most heated zone) put a boat of linkage of copper with a long hook made of steel wire with a diameter of 2 to 3 mm. a Tube furnace immediately connect with other devices and burned a portion of copper. The rate of transmission of oxygen must be maintained such that the liquid in the absorption vessel (figure 2, left part) were raised to an additional height of 2 to 3 cm When leaving the furnace in the absorption vessel gases begin to decolorize the iodine solution, pour the iodine solution at such a rate that the blue color did not disappear during burning of the sample. Burning sulphur is complete when the color of the solution in the absorption solution* remains constant and the same intensity with the color of the solution in the right part of the vessel for absorption.
________________
* The text matches the original. — Note the manufacturer’s database.

6.3.5 processing of the results of the analysis

6.3.5.1 Mass fraction of sulfur , %, is calculated by the formula

, (11)

where the titer of the iodine solution, expressed in grams of sulfur;

 — the volume of iodine solution consumed for titration, cm;

 — weight of copper,

6.3.5.2 For the result of the analysis taking the arithmetic mean of two parallel definitions, provided that the absolute difference between them in terms of repeatability does not exceed the values (with confidence probability of 0.95) limit of repeatability in table 1.

If the discrepancy between the results of parallel measurements exceed the limit of repeatability, perform the procedure described in the standard [2] (paragraph 5.2.2.1).

6.3.6 the Control of accuracy of analysis results

Control of accuracy of analysis results — for 3.14.

6.3.7 presentation of results of analysis

The results of the analysis include the following 3.15, the values of error analysis results are given in table 1.

6.4 the Method of infrared spectrometry

6.4.1 measurement Means, auxiliary devices, materials, solutions

When performing measurements using the following measuring instruments, auxiliary devices:

analyzer for sulfur, based on the principle of infrared spectrometry with an induction high-frequency furnace;

— the furnace shaft, providing a temperature of at least 1200 °C;

— refractory ceramic crucible, calcined at a temperature from 900 °C to 1200 °C for at least 4 hours;

WITH GOST 8.315 composition of copper or alloys based on copper or iron-based;

— medical forceps according to GOST 21241.

When performing measurements using the following materials:

— technical oxygen gas according to GOST 5583;

magnesium rate (anhydro) of the firm «LECO» or [17];

marshes: tungsten [18], iron [19] and other substances, providing the combustion and the results of control of the experience outlined in 6.4.2.1 above;

— yarn and fiber glass unidirectional GOST 10727;

— Askari of the firm «LECO» or [20].

6.4.2 Method of measurement

The method is based on measuring the absorption of gaseous sulfur dioxide (IV) in the infrared region of the spectrum after selecting it from a sample of metal combustion in high-frequency induction furnace in flowing oxygen.

6.4.2.1 above Measurement of the mass fraction of sulphur (at a mass proportion of from 0,0003% to 0.050%) by infrared spectrometry in the presence of flux

Preparation for measurements

Preparing the analyzer to work and his grading is carried out in accordance with the operation manual. For calibration you must use the standard samples for composition of copper or alloys based on copper or iron-based.

Measurements

General requirements for methods of measurements and safety requirements when performing measurements in accordance with sections 3 and 4.

Mass fraction of sulfur is determined simultaneously from the two batches.

The crucible is placed in a portion of the sample from the mass of 0.2000 to 1,0000 g, add the flux, the weight of which must be the same when conducting the reference experiment, the calibration and analysis, and conduct analysis as indicated in the supplied instructions.

Directly before measuring sample of the sample hold control experience. For this purpose, the crucible is placed a portion of the beach that mass, which is used in the analysis of the samples, and analyze as above.

Control experience should be considered satisfactory if the readings of the mass fraction of sulfur on the digital display does not exceed the error of the method of analysis (table 2). Error analysis method consider the error of the lower range determined intervals a mass fraction of sulfur.

Processing of measurement results

The results of measurements of sulphur mass fraction in percent on the display or printer of the automated analyzer.

The measurement results take the arithmetic mean value of two parallel measurements under the condition that the absolute difference between them in terms of repeatability does not exceed the values (with confidence probability of 0.95) limit of repeatability in table 2.

If the discrepancy between the results of parallel measurements exceeds the limit value of the frequency of occurrence, perform the procedure described in the standard [2] (paragraph 5.2.2.1).

6.4.2.2 Measurement of mass fraction of sulphur (at a mass fraction of from 0.0002% to 0,0050%) by infrared spectrometry without the use of flux

Preparation for measurements

Preparing the analyzer to work and his grading is carried out in accordance with the operation manual. The calibration should be carried out on CRMs for composition of copper from three parallel measurements.

In the case of a calibration analyzer factory re-calibration is not required. In the process of application of the analyzer is carried out, the stability control calibration in accordance with the manual.

Sample and analyze material samples should be the same.

If found, the average value of the mass fraction of sulfur in co differs from the certified value more than the value of error build the calibration characteristic, the calibration is repeated, calculating a linear multiplier for the correction of calibration in accordance with the manual. When you re excess value of the error of the construction of the calibration characteristics analysis of stop to ascertain and eliminate the causes. The value of uncertainty of calibration characteristics construction installed in the laboratory for a specific instance of a measuring instrument.

Measurements

General requirements for methods of measurements and safety requirements when performing measurements in accordance with sections 3 and 4.

Mass fraction of sulfur is determined from two parallel measurements.

The crucible is placed in a weighed test portion mass (1,000±0,200) g, using the tongs, put on the stand avtoagregatnogo the device to further carry out the analysis, as specified in the supplied instructions.

Processing of measurement results

The results of measurements of sulphur mass fraction in percent on the display of the computer.

The measurement results take the arithmetic mean value of two parallel measurements under the condition that the absolute difference between them in terms of repeatability does not exceed the values (with confidence probability of 0.95) limit of repeatability are given in table 3.

If the discrepancy between the results of parallel measurements exceeds the limit value of the frequency of occurrence, perform the procedure described in the standard [2] (paragraph 5.2.2.1).

6.4.3 accuracy Control of measurement results

Accuracy control of measurement results is in accordance with 3.14.

6.4.4 presentation of results of measurements

The results of measurements issued in accordance with 3.15, the values of error measurement results are shown in tables 2 and 3.

7 the Method of determining the mass fraction of phosphorus

7.1 Scope

This section established a definition of the mass fraction of phosphorus in copper in the range from 0,0003% to 0.06% by the photometric method.

The method is not applicable to the determination of the mass fraction of phosphorus in copper, according to GOST 859марок M00k and M00b.

7.2 Requirements for uncertainty analysis

The error analysis results of the mass fraction of phosphorus, the values of the limits of repeatability and reproducibility for a confidence probability of 0.95 shall be as given in table 4.


Table 4

Percentage

7.3 measurement Means, auxiliary devices, materials, solutions

When you perform analysis used the following measuring instruments, auxiliary devices:

— a photoelectric photometer or spectrophotometer with all accessories;

— special laboratory scales of accuracy class according to GOST 24104;

pipettes not lower than 2nd accuracy class according to GOST and GOST 29169 29227;

— volumetric flasks 2−50−2, 2−100−2, 2−1000−2 according GOST 1770;

— glasses-1−250 TC GOST 25336;

— flask KN-1−100−14/23 according to GOST 25336;

— a Buchner funnel according to GOST 9147;

— hour glass.

When you perform analysis used the following materials, solutions:

the filter paper according to GOST 12026;

filters obestochennye [21] or other medium density;

— hydrochloric acid according to GOST 3118;

— nitric acid according to GOST 4461 and diluted 2:1;

— a mixture of hydrochloric and nitric acids in the ratio 1:3, freshly prepared;

— ammonium undeviatingly meta GOST 9336, solution mass concentration of 2.5 g/DM;

— ammonium molybdate according to GOST 3765, recrystallized, solution mass concentration of 100 g/DM.

— hydrogen peroxide according to GOST 10929 and diluted 1:9;

— potassium permanganate according to GOST 20490, solution mass concentration of 0.2 mol/DM(1.);

— copper according to the GOST 859;

— potassium phosphate according to GOST odnosemjannyj 4198, dried at a temperature of from 80 °C to 90 °C for 1 h;

— sodium phosphate disodium GOST 11773, dried at a temperature of from 102 °C to 105 °C for 1 h;

— phosphorus solutions of known concentration;

— ammonia water according to GOST 3760;

— technical rectified ethyl alcohol according to GOST 18300.

7.4 Method of analysis

The method is based on the formation of phosphorus-molybdenum-vanadium heteroalicyclic in 1 M nitric acid solution. Optical density of the solution is measured at a wavelength of from 400 to 413 nm, or from 440 to 453 nm depending on the mass fraction of phosphorus.

7.5 Preparation for analysis

7.5.1 in the preparation of the solution vadeevaloo ammonium mass concentration of 2.5 g/DMweighed 2.5 g vadeevaloo ammonium dissolved in 650 cmof water, add 10 cmof nitric acid, add water to 1000 cmand mixed.

7.5.2 in the preparation of molybdate ammonium solution mass concentration of 100 g/DMinitially carried out the recrystallization of salt in the following manner: a sample of salt weighing 100 to 120 g dissolved in 400 cmof water at a temperature of 80 °C and filtered twice hot solution through a dense obezdolennyh filter «blue ribbon». To the obtained solution is added 250 g of ethyl alcohol, cooled and allowed to settle for 1 h. Precipitated crystals was filtered on a Buechner funnel. The resulting crystals of ammonium molybdate are dissolved, and again recrystallized, the crystals filtered off on a Buchner funnel, washed 2−3 times with ethanol with a volume of 20 to 30 cm, after which they are dried in air. Before application of the recrystallized salt solution is prepared as follows: a portion of 100 g of salt dissolved in water volume from 700 to 800 cmand go from 25 to 30 cmof ammonia. The solution was stirred, then filtered through cotton wool or paper pulp, top up with water to 1000 cmand mixed. Use freshly prepared.

7.5.3 For constructing the calibration graphs prepare solutions of known phosphorus concentration.

In preparing the solution And the mass of the phosphorus concentration to 0.1 mg/cma portion 0,4580 g twosemester sodium phosphate or 0,4390 g of single potassium phosphate is dissolved in water with volume from 50 to 70 cm, add 2 cmof nitric acid, the solution transferred to a volumetric flask with a capacity of 1000 cm, made up to the mark with water and mix.

In the preparation of a solution of mass concentration of phosphorus 0.025 mg/cmof 25 cmof the solution And placed in a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.

Solutions A and B stored in a plastic container. Solution B is freshly prepared use.

7.5.4 the Construction of the calibration graphs

7.5.4.1 When the mass fraction of phosphorus less than 0.001%

In a volumetric flask with a capacity of 50 cmeach are placed 0; 0,4; 1,0; 2,0; 3,0; 4,0 and 5.0 cmof solution B, which corresponds to 0; 10; 25; 50; 75; 100 and 125 mg of phosphorus, add 3 to 4 cmof nitric acid, pour 5 cmvadeevaloo ammonium 5 cmof molybdenic acid ammonium solution and add water to the mark. After adding of each solution the contents of the tubes mixed well. After 20 minutes, measure the optical density of the solution at a wavelength of from 400 to 413 nm in a cuvette with the thickness of the light absorbing layer 30 mm relative to the solution without added phosphorus.

7.5.4.2 When the mass fraction of phosphorus from 0.001% to 0,006% do the same as in 7.5.4.1, however, the amount of solution B is 0; 1,0; 2,0; 4,0; 6,0; 8,0; 10,0 and 12.0 cm, which corresponds to 0; 25; 50; 100; 150; 200; 250 and 300 µg phosphorus.

The optical density of solutions measured at a wavelength of from 400 to 413 nm in cuvettes with the thickness of the light absorbing layer 20 mm relative to the solution without added phosphorus.

7.5.4.3 If the mass fraction of phosphorus from 0.005% to 0.06%

In a volumetric flask with a capacity of 100 cmeach placed 0; 1,0; 2,5; 5,0; 7,5; 10,0; 12,0 and 13.0 cmsolution A, which corresponds to 0; 100; 250; 500; 750; 1000; 1200; 1300 micrograms of phosphorus, add 6 to 8 cmof nitric acid, 10 cmvadeevaloo ammonium 10 cmof a solution of molybdate of ammonium. After adding of each solution the contents of the tubes thoroughly mixed. After this, the solution in volumetric flask immediately topped up to the mark with water and mix. After 20 minutes, measure the optical density of the solution at a wavelength of from 440 to 453 nm in a cuvette with the thickness of the light absorbing layer 30 mm relative to the solution without added phosphorus.

7.5.4.4 When the mass fraction of phosphorus from 0.01% to 0.06% in eight cups with a capacity of 250 cm, each weighted according to 2,0000 g of copper (with a mass fraction of phosphorous is less than 0.0005%), add 0; 1,0; 2,5; 5,0; 7,5; 10,0; 12,0 and 13.0 cmsolution A, which corresponds to 0; 100; 250; 500; 750; 1000; 1200; 1300 mcg phosphorus. The solutions, if necessary, evaporated to a volume of 1 to 2 cm. Then the glasses are poured at 30 cmof nitric acid, diluted 2:1. The solution is heated, without boiling, until complete dissolution of copper. After dissolution of samples in low boiling removes oxides of nitrogen, without removing the watch glass. The solution was cooled, added 1 cmof solution of potassium permanganate (pink color) and leave the solution for 5 min Then heated to boiling, boiled for 1 min and cooled to a temperature of from 30 °C to 40 °C. Add 2 cmof hydrogen peroxide diluted 1:9, boil for 30 seconds, then add 10 cmof a solution of ammonium anadalucia and continue to boil for 1 min.

The solution was cooled and poured into a volumetric flask with a capacity of 100 cm.

Add 10 cmof molybdate ammonium solution with continuous stirring. After this, the solution in volumetric flask immediately topped up to the mark with water and mix. After 20 minutes, measure the optical density of the solution at a wavelength of from 440 to 453 nm in a cuvette with the thickness of the light absorbing layer 30 mm.

Solution comparison in the measurement of the optical density is a solution containing 2 g of copper (with a mass fraction of phosphorous is less than 0.0005%) and all reagents.

7.5.4.5 When the mass fraction of phosphorus from 0.001% to 0.06% with the use of a mixture of acids in ten cups with a capacity of 250 cm, each is placed 0; 0,8; 2,0 cmof a solution; 1,0; 2,5; 5,0; 7,5; 10,0; 12,0; 13,0 cmof solution A, which corresponds to 0; 20; 50; 100; 250; 500; 750; 1000; 1200; 1300 micrograms of phosphorus, flow from 18 to 20 cmof a mixture of hydrochloric and nitric acids in the ratio 1:3. Add 20 to 25 cmof water and boil for 3−4 min. the Solutions were cooled and placed in a volumetric flask with a capacity of 50 cm.

To the obtained solution poured with stirring 5 cmsolution vadeevaloo ammonium and 5 cmof molybdate ammonium solution, made up to the mark with water and mix. After 20 minutes, measure the optical density of the solution at a wavelength of from 440 to 453 nm in a cuvette with the thickness of the light absorbing layer 30 mm.

Solution comparison in the measurement of optical density is the solution not containing phosphorus.

The values of optical densities found in 7.5.4.1−7.5.4.5, and their corresponding values of phosphorus build calibration graphs.

7.6 Performing analysis

7.6.1 General requirements for methods of analysis and safety requirements when performing analyses in accordance with sections 3 and 4.

7.6.2 Determination of phosphorus at a mass fraction it from 0,0003% to 0.06%

A sample of copper weighing from 2.0 to 5.0 g depending on the mass fraction of phosphorus (table 5) were placed in a glass with a capacity of 250 cm, cover with a watch glass and dissolved in 30 cmof nitric acid, diluted 2:1 when heated, not allowing to boil (if necessary, acid is added in portions of 10 cm).


Table 5

Nitrogen oxides are removed by boiling weak solution in a closed volume (without removing the watch glass). The solution was cooled, added 1 cmof solution of potassium permanganate (pink color) and leave the solution for 5 min Then heated to boiling, boiled for 1 min and cooled to a temperature of from 30 °C to 40 °C. Add 2 cmof hydrogen peroxide diluted 1:9, boil for 1 min, add 5 cm(or 10 cmwhen diluted to 100 cm) of a solution of ammonium anadalucia and continue to boil for 1 min. the Solution was cooled and poured into based on the content of phosphorus (table 5) in a volumetric flask with a capacity of 50 cmor 100 cm. With constant stirring are added dropwise 5 cm(10 cm) of a solution of molybdate of ammonium. After this, the solution is immediately topped up to the mark with water and mix.

After 20 minutes, measure the optical density of the solution. The wavelength and the thickness of the light absorbing layer shown in table 5. The comparison solution is a solution containing a sample of copper and all reagents, except molybdate of ammonium.

At the same time carried out two test experience, which in a glass with a capacity of 250 cm30 cm pournitric acid, diluted 2:1, cover with a watch glass and put through a course of analysis.

Solution comparison to reference experiment is a solution containing from 3 to 4 cm(6 to 8 cm) of nitric acid, 25 cmwater and 5 cm(10 cm) solution vadeevaloo ammonium. The solution was transferred to volumetric flask with a capacity of 50 cm(100 cm) and top up with water to the mark.

The average value of the optical density of the solutions of the control experiments is subtracted from the value of the optical density of the analyzed solution. The amount of phosphorus set by the calibration schedule is constructed, as described in 7.5.4.1−7.5.4.3.

7.6.3 Determination of phosphorus at a mass fraction it from 0.01% to 0.06% may be performed as follows.

A sample of copper with a mass of 2.0 g was placed in a beaker with a capacity of 250 cmand carry out the determination in 7.6.2, measure the optical density of the solution at a wavelength of from 440 to 453 nm in a cuvette with the thickness of the light absorbing layer 30 mm. with a Solution of comparison in the measurement of the optical density is a solution containing 2 g of copper (with a mass fraction of phosphorous is less than 0.0005%) held through the course of the analysis. The mass of phosphorus determined according to the calibration schedule, constructed in the presence of 2.0 g of copper (with a mass fraction of phosphorous is less than 0.0005%) as described in 7.5.4.4.

7.6.4 Determination of phosphorus at a mass fraction it from 0.001% to 0.06% may be performed using a mixture of acids.

A sample of copper with a mass of 2.0 g was placed in a conical flask with a capacity of 100 cm, flow 18 to 20 cmof a mixture of hydrochloric and nitric acids in the ratio 1:3, heated to dissolve the sample and then heating is continued until the removal of nitrogen oxides, preventing the boiling point of the solution. Then add 20 to 25 cmof water and boil for 3 to 4 min. the Solution was cooled and placed in a volumetric flask with a capacity of 50 cm.

To the obtained solution poured with stirring 5 cmsolution vadeevaloo ammonium and 5 cmof molybdate ammonium solution, made up to the mark with water and mix. After 20 minutes, measure the optical density of the solution at a wavelength of from 440 to 453 nm in a cuvette with the thickness of the light absorbing layer 30 mm.

Solution comparison in the measurement of optical density is the solution not containing ammonium molybdate.

Simultaneously, through the analysis carried out two test experience. Solution comparison is the solution not containing ammonium molybdate.

The average value of the optical density of the solutions of the control experiments is subtracted from the value of the optical density of the analyzed solution.

The mass of phosphorus determined according to the calibration schedule is constructed, as described in 7.5.4.5.

7.7 Processing of analysis results

7.7.1 Mass fraction of phosphorus , %, is calculated by the formula

, (12)

where is the mass of phosphorus was found in the calibration schedule, mcg;

 — weight of copper,

7.7.2 For the result of the analysis taking the arithmetic mean of two parallel definitions, provided that the absolute difference between them in terms of repeatability does not exceed the values (with confidence probability of 0.95) limit of repeatability shown in table 4.

If the discrepancy between the results of parallel measurements exceed the limit of repeatability, perform the procedure described in the standard [2] (paragraph 5.2.2.1).

7.8 Control of accuracy of analysis results

Control of accuracy of analysis results — for 3.14.

7.9 the results of the analysis

The results of the analysis include the following 3.15, the values of uncertainty analysis results given in table 4.

8 Methods of determining the mass fraction of iron

8.1 Scope

In this section the photometric set (with mass fraction from 0.0005% to 0.100%) and atomic absorption (at a mass fraction of 0.0008% to 0.06%) methods for determination of mass fraction of iron in copper.

8.2 Requirements for uncertainty analysis

Error analysis results the mass fraction of iron, the limit values of repeatability and reproducibility for a confidence probability of 0.95 shall be as given in table 6.


Table 6

Percentage

8.3 Photometric method

8.3.1 measurement Means, auxiliary devices, materials, solutions

When you perform analysis used the following measuring instruments, auxiliary devices:

— a photoelectric photometer or spectrophotometer with all accessories necessary for measurements at a wavelength of 425 nm;

centrifuge with all accessories;

— special laboratory scales of accuracy class according to GOST 24104;

pipettes not lower than 2nd accuracy class according to GOST and GOST 29169 29227;

— volumetric flasks 2−25−2, 2−50−2, 2−1000−2 according GOST 1770;

— glasses-1−250 TS-1−400 TCS according to GOST 25336;

— hour glass.

When you perform analysis used the following materials, solutions:

— hydrochloric acid according to GOST 3118 and diluted 1:1;

— sulfuric acid according to GOST 4204, diluted 1:4;

water mediterreaneo;

— nitric acid of high purity according to GOST 11125, diluted 1:1, or nitric acid according to GOST 4461 (boiled to remove oxides of nitrogen), diluted 1:1;

— ammonia water according to GOST 3760, diluted 1:19;

— aljumokalievyh alum (aluminum-potassium sulphate) according to GOST 4329;

— primary aluminium GOST 11069, grade A 999 or 995;

— a solution of aluminium;

— the oxide of lanthanum;

— lanthanum nitrate shestibalny [22] or lanthanum chloride;

— a solution of lanthanum mass concentration of 1 mg/cm;

— sulfosalicylic acid according to GOST 4478, solution mass concentration of 100 g/DM;

— ammonium chloride according to GOST 3773, solution mass concentration of 200 g/DM;

— iron carbonyl [19] or more, containing not less than 99.9% of the main substance;

— iron trioxide, previously dried at 110 °C;

— iron solution of known concentration.

8.3.2 Method of analysis

The method is based on formation of yellow complex compound of iron with sulfosalicylic acid in an ammonia solution, after separation of iron from copper by precipitation of its hydroxide of aluminum or lanthanum. Optical density of the solution is measured at a wavelength of 425 nm.

8.3.3 Preparing to run the analysis
8.3.3.1 in the preparation of solution of aluminum weighed 1 g of aluminium is dissolved in a volume of 15 to 20 cmof hydrochloric acid or a suspension of 20 g of aluminum sulfate-potassium dissolved in water with the addition of 15 cmof hydrochloric acid. Solution top up with water to 1000 cmand mixed.

8.3.3.2 in the preparation of a solution of lanthanum mass concentration of 1 mg/cmweighed 1.2 g of lanthanum oxide dissolved in 15 cmof hydrochloric acid diluted 1:1, or a portion of 2.7 g of lanthanum chloride or 3.1 g of lanthanum nitrate dissolved in water, add 10 cmof hydrochloric acid diluted 1:1. Solution top up with water to 1000 cm.

8.3.3.3 For constructing the calibration graphs prepared iron solution of known concentration.

In preparing the solution And the mass concentration of iron to 0.1 mg/cma portion 0,1430 g of iron trioxide or a portion 0,1000 g of iron dissolved in 30 cmof hydrochloric acid diluted 1:1, when heated. If necessary, the iron should be docility nitric acid, diluted 1:1. The solution was cooled and transferred into a measuring flask with volume capacity of 1000 cm, made up to the mark with water and mix.

In the preparation of a solution of mass concentration of iron, 0.02 mg/cm20 cmsolution And transferred with a pipette into a measuring flask with a capacity of 100 cm, pour 2 cmof hydrochloric acid diluted 1:1, made up to the mark with water and mix.

8.3.3.4 Construction of calibration curve

In the glasses put 0; 0,2; 0,5; 1,0; 2,0; 3,0; 4,0 and 5.0 cmof solution B, which corresponds to 0; 4; 10; 20; 40; 60; 80 and 100 mcg of iron, add 5 cmof nitric acid, 25 cmwater, 5 cmof a solution of aluminum or lanthanum. The separation of iron, dissolution of hydroxides with hydrochloric acid and measurement of optical density of solutions is performed, as indicated in 8.3.4.2.

According to the obtained values of optical density and corresponding grades of iron to build the calibration graph.

8.3.4 Performing analysis

8.3.4.1 General requirements for methods of analysis and safety requirements when performing analyses in accordance with sections 3 and 4.

8.3.4.2 Determination of iron in its mass fraction from 0.0005% to 0.01%

A sample of copper weighing 1,0000 g placed in a beaker with a capacity of 100 cmand dissolved in 5 cmof nitric acid. Nitrogen oxides can be removed by careful boiling in a beaker covered with a watch glass. The solution is diluted with 25 cmof water, add 5 cmof a solution of aluminum or lanthanum, then with constant stirring, a solution of ammonia in such quantity that all the copper went to the compound (blue solution). Solution and the precipitate is heated to a temperature from 70 °C to 80 °C and kept at this temperature for 20 min. After cooling, the hydroxides are separated by filtration or centrifugation.

For centrifuging the contents of the beaker were transferred to a centrifuge tube and centrifuging for 2 min. Then the solution above the precipitate is drained (sivunirmut), and the residue in the tube twice washed with 10 cmof ammonia solution diluted 1:19, each time draining the flushing solution. To the residue in the test tube and add 2cmof hot hydrochloric acid, diluted 1:1, and after dissolution of the precipitate add 10 cmof water. Then under stirring added dropwise a solution of ammonia until the precipitation of hydroxides. After 10 minutes the contents of tubes tsentrifugirujut, and the solution above the precipitate is drained. The residue in the tube twice washed with 10 cmof ammonia solution diluted 1:19, dissolved in 5 cmof hydrochloric acid diluted 1:1, and the solution was transferred to a beaker, in which was conducted the deposition.

The contents of the glass after deposition of hydroxides is filtered at the filter «white ribbon». The filter cake was washed 5−6 times with a hot solution of ammonia, diluted 1:19. The precipitate is then washed from the filter with a jet of hot water into the Cup, which was held a deposition, add 5 cmof hydrochloric acid and the contents of the beaker is heated to dissolve the precipitate (the solution should be transparent). Solution into the beaker cool, add 25 cmof water and periostat hydroxides by ammonia solution.

The precipitate of hydroxides was filtered on the same filter and washed on the filter 5−6 times a hot ammonia solution, diluted 1:19. Then the precipitate from the filter washed with hot water into a glass, which conducted the deposition. The precipitate of hydroxides on the filter is dissolved in a volume of 5 to 10 cmof hydrochloric acid and collect the solution in the beaker in which the precipitated hydroxides. The filter was washed 2−3 times with small portions of hot water, adding the washings to the main solution in the beaker.

The solution was evaporated to a volume of 2 to 3 cmand, after cooling, is poured into a measuring flask with a capacity of 50 cm. The glass is washed with a solution of ammonium chloride, 2 times 5 cm. To the solution in the volumetric flask, add 2.5 cmof a solution of sulfosalicylic acid, mix, add 5 cmof ammonia solution and add water to the mark. Optical density of the solution is measured within 30 min at a wavelength of 425 nm in a cuvette with the thickness of the light absorbing layer 50 mm Solution of comparison in the measurement of optical density is water.

At the same time carried out two test experience with all the applied reagents.

The average value of the optical density of the solutions of the control experiments is subtracted from the value of the optical density of the analyzed solution.

Weight of iron in the solution set of the calibration schedule, constructed as specified in 8.3.3.4.

8.3.4.3 Determination of iron in its mass fraction from 0.01% to 0.1%

Dissolution and separation of iron perform in the same manner as described in 8.3.4.2. Hydrochloric acid to the solution obtained after dissolution of the hydroxide, add 20 cmof hydrochloric acid diluted 1:1, and the solution transferred to a volumetric flask with a capacity of 50 cm, made up to the mark with water and mix; 5 cmof this solution was transferred by pipette into a measuring flask with a capacity of 25 cm, add 10 cmof a solution of ammonium chloride, 2.5 cmsulfosalicylic acid solution, mix, add 5 cmof ammonia, made up to the mark with water and mix. Next, do the same, as indicated in 8.3.4.2.

8.4 Atomic absorption method

8.4.1 measurement Means, auxiliary devices, materials, solutions

When you perform analysis used the following measuring instruments, auxiliary devices:

— spectrophotometer of atomic absorption with the source of iron;

— air compressor;

— special laboratory scales of accuracy class according to GOST 24104;

pipettes not lower than 2nd accuracy class according to GOST and GOST 29169 29227;

— volumetric flasks 2−25−2, 2−100−2, 2−1000−2 according GOST 1770;

— flasks KN-2−100−14/23 TCS, KN-2−250−19/26 TCS GOST 25336;

— glasses-1−250 TCS according to GOST 25336.

When you perform analysis used the following materials, solutions:

— acetylene according to GOST 5457;

water mediterreaneo;

— nitric acid of high purity according to GOST 11125, diluted 1:1, or nitric acid according to GOST 4461 (boiled to remove oxides of nitrogen), diluted 1:1;

— copper, for spectral analysis, containing 6,8·10% iron, or electrolyte copper is established with a mass fraction of iron;

— iron carbonyl [19] or more, containing not less than 99.9% of the main substance;

— iron solution of known concentration.