ICS 77.080.01
CCS H 11
National Standard of the People's Republic of China
GB/T 223.23-2026
Replace GB/T 223.23-2008 and GB/T 223.25-1994
Iron, steel and alloy - Determination of nickel content - Spectrophotometric method and gravimetric method
钢铁及合金 镍含量的测定分光光度法和重量法
(English Translation)
Issue date: 2026-08-28 Implementation date: 2027-03-01
Issued by the State Administration for Market Regulation of the People's Republic of China
the Standardization Administration of the People's Republic of China
WARNING - Persons using this document shall have formal laboratory practice. This standard does not purport to address all of the safety concerns. It is the responsibility of the user to establish appropriate safety and health practice. and to ensure compliance with the conditions specified in relevant national laws and regulations.
1 Scope
This document describes methods for the determination of nickel content in iron, steel and alloy using dimethylglyoxime spectrophotometric method and dimethylglyoxime gravimetric method.
The applicable scope of this document is as follows: Method 1 (Direct dimethylglyoxime spectrophotometric method) is applicable to the determination of nickel content of 0.030% to 2.00% in pig iron, iron powder, carbon steel and alloy steel; Method 2 (Extraction separation - dimethylglyoxime spectrophotometric method) is applicable to the determination of nickel content of 0.010% to 0.50% in pig iron, carbon steel, alloy steel and precision alloys; Method 3 (Dimethylglyoxime gravimetric method) is applicable to the determination of nickel content above 2.00% in carbon steel, alloy steel, precision alloys and superalloys; Method 4 (Dimethylglyoxime spectrophotometric method) is applicable to the determination of nickel content of 0.10% to 2.00% in steel.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6379.1 Accuracy (trueness and precision) of measurement methods and results - Part 1 : General principles and definitions
GB/T 6379.2 Accuracy (trueness and precision) of measurement methods and results - Part 2:Basic method for the determination of repeatability and reproducibility of a standard measurement method
GB/T 6682 Water for analytical laboratory use - Specification and test methods
GB/T 7729 Chemical analysis of metallurgical products - General rule for spectrophotometric methods
GB/T 12806 Laboratory glassware - One-mark volumetric flasks
GB/T 12808 Laboratory glassware - One-mark pipettes
GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition
3 Terms and definitions
No terms and definitions are specified in this document.
4 Method 1 Direct dimethylglyoxime spectrophotometric method
4.1 Principle
The sample is dissolved in acid, perchloric acid is fumed to oxidize chromium to the hexavalent state, iron is masked with sodium tartrate, and in a strongly alkaline medium, with ammonium persulfate as the oxidizing agent, nickel reacts with dimethylglyoxime to form a red complex, and its absorbance is measured.
In the color development solution, manganese content greater than 1.5 mg, copper content greater than 0.2 mg, or cobalt content greater than 0.1 mg will interfere with the determination.
4.2 Reagents
Unless otherwise specified, only reagents confirmed to be of analytical reagent grade and grade 2 water as specified in GB/T 6682, or water of equivalent purity, shall be used in the analysis.
4.2.1 Ethanol
95% (mass fraction) or above.
4.2.2 Perchloric acid
ρ approximately 1.67 g/mL.
4.2.3 Nitric acid (2+3) solution
Dilute with nitric acid having a ρ of approximately 1.42 g/mL.
4.2.4 Hydrochloric acid⁃nitric acid mixed acid (1+1+2) solution
4.2.5 Sodium tartrate solution, 300 g/L
4.2.6 Sodium hydroxide solution, 100 g/L
Weigh 100 g of sodium hydroxide, dissolve in water, dilute to 1000 mL, and store in a plastic bottle.
4.2.7 Dimethylglyoxime solution, 10 g/L
Prepare with ethanol (4.2.1).
4.2.8 Ammonium persulfate solution, 40 g/L, prepared immediately before use.
4.2.9 Nickel standard solution, 100.0 μg/mL
Weigh 0.1000 g of pure nickel (mass fraction greater than 99.99%), place in a 150 mL Erlenmeyer flask, add 20 mL of nitric acid (4.2.3), heat to dissolve, cool to room temperature, transfer to a 1000 mL volumetric flask, dilute to the mark with water, and mix well.
1 mL of this standard solution contains 100.0 μg of nickel.
4.2.10 Nickel standard solution, 10.0 μg/mL
Pipette 25.00 mL of nickel standard solution (4.2.9) into a 250 mL volumetric flask, add 5 mL of nitric acid (4.2.3), dilute to the mark with water, and mix well.
1 mL of this standard solution contains 10.0 μg of nickel.
4.3 Apparatus and equipment
All glassware shall be of Class A specified in GB/T 12806 and GB/T 12808.
Spectrophotometer, which shall meet the requirements specified in GB/T 7729.
4.4 Sampling and sample preparation
Sampling and sample preparation shall be carried out in accordance with GB/T 20066 or appropriate national standard(s).
4.5 Analysis procedure
Warning: Fuming with perchloric acid may cause an explosion, usually in the presence of ammonia, nitrous fumes, or organic matter.
4.5.1 Mass of test portion
Depending on the nickel content (mass fraction) in the sample, weigh the test portion in accordance with Table 1, to the nearest 0.001 g.
Table 1 Mass of test portion
Nickel content (mass fraction)/% Mass of test portion/g
0.03~0.10 0.50
>0.10~0.50 0.20
>0.50~2.00 0.10
4.5.2 Blank test
Carry out a blank test along with the test portion.
4.5.3 Determination
4.5.3.1 Place the test portion (4.5.1) in a 150 mL Erlenmeyer flask, add 5 mL to 10 mL nitric acid (4.2.3) or hydrochloric acid ⁃ nitric acid mixed acid (4.2.4), heat to dissolve, then add 3 mL to 5 mL perchloric acid (4.2.2), evaporate to fumes of perchloric acid until a moist salt residue is obtained, remove it, and cool slightly.
4.5.3.2 Add a small amount of water to dissolve the salts. After cooling, transfer to a 100 mL volumetric flask (when the mass fraction of nickel is 0.03% to 0.10%, transfer to a 50 mL volumetric flask), dilute to the mark with water, and mix well. If any precipitate is present, remove it by dry filtration.
4.5.3.3 Pipette two 10.00 mL aliquots (when the mass fraction of nickel is 1.00% to 2.00%, pipette 5.00 mL) of the test solution (4.5.3.2), place them separately in 50 mL volumetric flasks, and proceed as described in a) and b), respectively.
a) Color development solution: Add 10 mL sodium tartrate solution (4.2.5), 10 mL sodium hydroxide solution (4.2.6), 2 mL dimethylglyoxime solution (4.2.7), and 5 mL ammonium persulfate solution (4.2.8). Mix well after each reagent addition, dilute to the mark with water, and mix well.
b) Reference solution: Add 10 mL sodium tartrate solution (4.2.5), 10 mL sodium hydroxide solution (4.2.6), 2 mL ethanol (4.2.1), and 5 mL ammonium persulfate solution (4.2.8), dilute to the mark with water, and mix well.
4.5.3.4 After standing at room temperature for 10 min to 20 min, place a portion of the color development solution [4.5.3.3 a)] in a 2 cm or 3 cm cuvette, use the reference solution [4.5.3.3 b)] as reference, and measure the absorbance at a wavelength of 530 nm on a spectrophotometer. Subtract the absorbance value of the blank solution from the measured absorbance value of the color development solution, and read the corresponding amount of nickel from the calibration curve.
4.5.4 Preparation of the calibration curve
Pipette 0 mL, 2.00 mL, 4.00 mL, 6.00 mL, 8.00 mL, and 10.00 mL of nickel standard solution (4.2.10), place each in a 50 mL volumetric flask, develop the color according to 4.5.3.3 a), and measure the absorbance according to 4.5.3.4, taking the zero point of the calibration curve as reference. Plot the calibration curve with the mass of nickel as the abscissa and the absorbance value as the ordinate.
4.6 Expression of results
4.6.1 Calculation method
The nickel content is expressed as a mass fraction wNi, with the value expressed in %, and is calculated according to formula (1):
(1)
Contents
Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Method 1 Direct dimethylglyoxime spectrophotometric method
5 Method 2 Extraction separation -dimethylglyoxime spectrophotometric method
6 Method 3 Dimethylglyoxime gravimetric method
7 Method 4 Dimethylglyoxime spectrophotometric method
8 Test report
Annex A (informative) Constituent parts of GB/T
Annex B (informative) Method 1 Direct dimethylglyoxime spectrophotometric method Additional information on the cooperative precision test
Annex C (informative) Method 2 Extraction separation ⁃ dimethylglyoxime spectrophotometric method Additional information on the cooperative precision test
Annex D (informative) Method 3 Dimethylglyoxime gravimetric method Additional information on the cooperative precision test
Annex E (informative) Method 4 Dimethylglyoxime spectrophotometric method Additional information from international interlaboratory tests
Annex F (informative) Method 4 Dimethylglyoxime spectrophotometric method Graphical representation of precision data
Bibliography
ICS 77.080.01
CCS H 11
National Standard of the People's Republic of China
GB/T 223.23-2026
Replace GB/T 223.23-2008 and GB/T 223.25-1994
Iron, steel and alloy - Determination of nickel content - Spectrophotometric method and gravimetric method
钢铁及合金 镍含量的测定分光光度法和重量法
(English Translation)
Issue date: 2026-08-28 Implementation date: 2027-03-01
Issued by the State Administration for Market Regulation of the People's Republic of China
the Standardization Administration of the People's Republic of China
WARNING - Persons using this document shall have formal laboratory practice. This standard does not purport to address all of the safety concerns. It is the responsibility of the user to establish appropriate safety and health practice. and to ensure compliance with the conditions specified in relevant national laws and regulations.
1 Scope
This document describes methods for the determination of nickel content in iron, steel and alloy using dimethylglyoxime spectrophotometric method and dimethylglyoxime gravimetric method.
The applicable scope of this document is as follows: Method 1 (Direct dimethylglyoxime spectrophotometric method) is applicable to the determination of nickel content of 0.030% to 2.00% in pig iron, iron powder, carbon steel and alloy steel; Method 2 (Extraction separation - dimethylglyoxime spectrophotometric method) is applicable to the determination of nickel content of 0.010% to 0.50% in pig iron, carbon steel, alloy steel and precision alloys; Method 3 (Dimethylglyoxime gravimetric method) is applicable to the determination of nickel content above 2.00% in carbon steel, alloy steel, precision alloys and superalloys; Method 4 (Dimethylglyoxime spectrophotometric method) is applicable to the determination of nickel content of 0.10% to 2.00% in steel.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6379.1 Accuracy (trueness and precision) of measurement methods and results - Part 1 : General principles and definitions
GB/T 6379.2 Accuracy (trueness and precision) of measurement methods and results - Part 2:Basic method for the determination of repeatability and reproducibility of a standard measurement method
GB/T 6682 Water for analytical laboratory use - Specification and test methods
GB/T 7729 Chemical analysis of metallurgical products - General rule for spectrophotometric methods
GB/T 12806 Laboratory glassware - One-mark volumetric flasks
GB/T 12808 Laboratory glassware - One-mark pipettes
GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition
3 Terms and definitions
No terms and definitions are specified in this document.
4 Method 1 Direct dimethylglyoxime spectrophotometric method
4.1 Principle
The sample is dissolved in acid, perchloric acid is fumed to oxidize chromium to the hexavalent state, iron is masked with sodium tartrate, and in a strongly alkaline medium, with ammonium persulfate as the oxidizing agent, nickel reacts with dimethylglyoxime to form a red complex, and its absorbance is measured.
In the color development solution, manganese content greater than 1.5 mg, copper content greater than 0.2 mg, or cobalt content greater than 0.1 mg will interfere with the determination.
4.2 Reagents
Unless otherwise specified, only reagents confirmed to be of analytical reagent grade and grade 2 water as specified in GB/T 6682, or water of equivalent purity, shall be used in the analysis.
4.2.1 Ethanol
95% (mass fraction) or above.
4.2.2 Perchloric acid
ρ approximately 1.67 g/mL.
4.2.3 Nitric acid (2+3) solution
Dilute with nitric acid having a ρ of approximately 1.42 g/mL.
4.2.4 Hydrochloric acid⁃nitric acid mixed acid (1+1+2) solution
4.2.5 Sodium tartrate solution, 300 g/L
4.2.6 Sodium hydroxide solution, 100 g/L
Weigh 100 g of sodium hydroxide, dissolve in water, dilute to 1000 mL, and store in a plastic bottle.
4.2.7 Dimethylglyoxime solution, 10 g/L
Prepare with ethanol (4.2.1).
4.2.8 Ammonium persulfate solution, 40 g/L, prepared immediately before use.
4.2.9 Nickel standard solution, 100.0 μg/mL
Weigh 0.1000 g of pure nickel (mass fraction greater than 99.99%), place in a 150 mL Erlenmeyer flask, add 20 mL of nitric acid (4.2.3), heat to dissolve, cool to room temperature, transfer to a 1000 mL volumetric flask, dilute to the mark with water, and mix well.
1 mL of this standard solution contains 100.0 μg of nickel.
4.2.10 Nickel standard solution, 10.0 μg/mL
Pipette 25.00 mL of nickel standard solution (4.2.9) into a 250 mL volumetric flask, add 5 mL of nitric acid (4.2.3), dilute to the mark with water, and mix well.
1 mL of this standard solution contains 10.0 μg of nickel.
4.3 Apparatus and equipment
All glassware shall be of Class A specified in GB/T 12806 and GB/T 12808.
Spectrophotometer, which shall meet the requirements specified in GB/T 7729.
4.4 Sampling and sample preparation
Sampling and sample preparation shall be carried out in accordance with GB/T 20066 or appropriate national standard(s).
4.5 Analysis procedure
Warning: Fuming with perchloric acid may cause an explosion, usually in the presence of ammonia, nitrous fumes, or organic matter.
4.5.1 Mass of test portion
Depending on the nickel content (mass fraction) in the sample, weigh the test portion in accordance with Table 1, to the nearest 0.001 g.
Table 1 Mass of test portion
Nickel content (mass fraction)/% Mass of test portion/g
0.03~0.10 0.50
>0.10~0.50 0.20
>0.50~2.00 0.10
4.5.2 Blank test
Carry out a blank test along with the test portion.
4.5.3 Determination
4.5.3.1 Place the test portion (4.5.1) in a 150 mL Erlenmeyer flask, add 5 mL to 10 mL nitric acid (4.2.3) or hydrochloric acid ⁃ nitric acid mixed acid (4.2.4), heat to dissolve, then add 3 mL to 5 mL perchloric acid (4.2.2), evaporate to fumes of perchloric acid until a moist salt residue is obtained, remove it, and cool slightly.
4.5.3.2 Add a small amount of water to dissolve the salts. After cooling, transfer to a 100 mL volumetric flask (when the mass fraction of nickel is 0.03% to 0.10%, transfer to a 50 mL volumetric flask), dilute to the mark with water, and mix well. If any precipitate is present, remove it by dry filtration.
4.5.3.3 Pipette two 10.00 mL aliquots (when the mass fraction of nickel is 1.00% to 2.00%, pipette 5.00 mL) of the test solution (4.5.3.2), place them separately in 50 mL volumetric flasks, and proceed as described in a) and b), respectively.
a) Color development solution: Add 10 mL sodium tartrate solution (4.2.5), 10 mL sodium hydroxide solution (4.2.6), 2 mL dimethylglyoxime solution (4.2.7), and 5 mL ammonium persulfate solution (4.2.8). Mix well after each reagent addition, dilute to the mark with water, and mix well.
b) Reference solution: Add 10 mL sodium tartrate solution (4.2.5), 10 mL sodium hydroxide solution (4.2.6), 2 mL ethanol (4.2.1), and 5 mL ammonium persulfate solution (4.2.8), dilute to the mark with water, and mix well.
4.5.3.4 After standing at room temperature for 10 min to 20 min, place a portion of the color development solution [4.5.3.3 a)] in a 2 cm or 3 cm cuvette, use the reference solution [4.5.3.3 b)] as reference, and measure the absorbance at a wavelength of 530 nm on a spectrophotometer. Subtract the absorbance value of the blank solution from the measured absorbance value of the color development solution, and read the corresponding amount of nickel from the calibration curve.
4.5.4 Preparation of the calibration curve
Pipette 0 mL, 2.00 mL, 4.00 mL, 6.00 mL, 8.00 mL, and 10.00 mL of nickel standard solution (4.2.10), place each in a 50 mL volumetric flask, develop the color according to 4.5.3.3 a), and measure the absorbance according to 4.5.3.4, taking the zero point of the calibration curve as reference. Plot the calibration curve with the mass of nickel as the abscissa and the absorbance value as the ordinate.
4.6 Expression of results
4.6.1 Calculation method
The nickel content is expressed as a mass fraction wNi, with the value expressed in %, and is calculated according to formula (1):
(1)
Contents of GB/T 223.23-2026
Contents
Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Method 1 Direct dimethylglyoxime spectrophotometric method
5 Method 2 Extraction separation -dimethylglyoxime spectrophotometric method
6 Method 3 Dimethylglyoxime gravimetric method
7 Method 4 Dimethylglyoxime spectrophotometric method
8 Test report
Annex A (informative) Constituent parts of GB/T
Annex B (informative) Method 1 Direct dimethylglyoxime spectrophotometric method Additional information on the cooperative precision test
Annex C (informative) Method 2 Extraction separation ⁃ dimethylglyoxime spectrophotometric method Additional information on the cooperative precision test
Annex D (informative) Method 3 Dimethylglyoxime gravimetric method Additional information on the cooperative precision test
Annex E (informative) Method 4 Dimethylglyoxime spectrophotometric method Additional information from international interlaboratory tests
Annex F (informative) Method 4 Dimethylglyoxime spectrophotometric method Graphical representation of precision data
Bibliography
