GB/T 38812.1-2020 Direct reduced iron—Determination of iron(Ⅱ) content—The potassium dichromate titrimetric method after decomposition of sample by ferric chloride (English)
GB/T 38812.1-2020 Direct reduced iron - Determination of iron (II) content - The potassium dichromate titrimetric method after decomposition of sample by ferric chloride
WARNING - Persons using this Part shall be familiar with normal laboratory practice. This part does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health measures and to ensure compliance with any national regulatory conditions.
1 Scope
This part of GB/T 38812 specifies the potassium dichromate titrimetric method after decomposition of sample by ferric chloride for the determination of iron (II) content.
This part is applicable to the determination of iron (II) content in direct reduced iron, with the determination range (mass fraction) of 1.00% to 40.00%.
2 Normative references
The following referenced documents are indispensable for the application 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 6682 Water for analytical laboratory use - Specification and test methods
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 12805 Laboratory glassware - Burettes
GB/T 12806 Laboratory glassware - One-mark volumetric flasks
GB/T 12808 Laboratory glassware - One mark pipettes
GB/T 24239 Direct reduced iron and hot briquetted iron - Sampling and sample preparation
3 Principle
The test portion is dissolved in ferric chloride solution. After filtration and separation, the residue on the filter is dissolved in hydrochloric acid and potassium fluoride under air-isolated conditions. In a sulfuric-phosphoric acid medium, with sodium diphenylamine sulfonate as the indicator, titrate with potassium dichromate standard solution until the solution turns purple as the end point. The mass fraction of iron (II) is calculated based on the consumed volume of potassium dichromate standard solution.
4 Reagents and materials
During the analysis, only recognized analytical grade reagents and water with purity of Grade III or higher as specified in GB/T 6682 shall be used.
4.1 Sodium bicarbonate, solid.
4.2 Hydrochloric acid, ρ≈1.19 g/mL.
4.3 Phosphoric acid, ρ ≈ 1.70 g/mL.
4.4 Sulfuric acid, ρ ≈ 1.84 g/mL.
Contents
Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Apparatus
6 Sampling and sample preparation
7 Analytical procedure
8 Calculation and expression of analysis results
9 Test report
Annex A (Normative) Flow chart of procedure for acceptance of specimen analysis results
GB/T 38812.1-2020 Direct reduced iron—Determination of iron(Ⅱ) content—The potassium dichromate titrimetric method after decomposition of sample by ferric chloride (English)
Standard No.
GB/T 38812.1-2020
Status
valid
Language
English
File Format
PDF
Word Count
3000 words
Translation Price(USD)
90.0
Implemented on
2020-12-1
Delivery
via email in 1 business day
Detail of GB/T 38812.1-2020
Standard No.
GB/T 38812.1-2020
English Name
Direct reduced iron—Determination of iron(Ⅱ) content—The potassium dichromate titrimetric method after decomposition of sample by ferric chloride
GB/T 38812.1-2020 Direct reduced iron - Determination of iron (II) content - The potassium dichromate titrimetric method after decomposition of sample by ferric chloride
WARNING - Persons using this Part shall be familiar with normal laboratory practice. This part does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health measures and to ensure compliance with any national regulatory conditions.
1 Scope
This part of GB/T 38812 specifies the potassium dichromate titrimetric method after decomposition of sample by ferric chloride for the determination of iron (II) content.
This part is applicable to the determination of iron (II) content in direct reduced iron, with the determination range (mass fraction) of 1.00% to 40.00%.
2 Normative references
The following referenced documents are indispensable for the application 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 6682 Water for analytical laboratory use - Specification and test methods
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 12805 Laboratory glassware - Burettes
GB/T 12806 Laboratory glassware - One-mark volumetric flasks
GB/T 12808 Laboratory glassware - One mark pipettes
GB/T 24239 Direct reduced iron and hot briquetted iron - Sampling and sample preparation
3 Principle
The test portion is dissolved in ferric chloride solution. After filtration and separation, the residue on the filter is dissolved in hydrochloric acid and potassium fluoride under air-isolated conditions. In a sulfuric-phosphoric acid medium, with sodium diphenylamine sulfonate as the indicator, titrate with potassium dichromate standard solution until the solution turns purple as the end point. The mass fraction of iron (II) is calculated based on the consumed volume of potassium dichromate standard solution.
4 Reagents and materials
During the analysis, only recognized analytical grade reagents and water with purity of Grade III or higher as specified in GB/T 6682 shall be used.
4.1 Sodium bicarbonate, solid.
4.2 Hydrochloric acid, ρ≈1.19 g/mL.
4.3 Phosphoric acid, ρ ≈ 1.70 g/mL.
4.4 Sulfuric acid, ρ ≈ 1.84 g/mL.
Contents of GB/T 38812.1-2020
Contents
Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Apparatus
6 Sampling and sample preparation
7 Analytical procedure
8 Calculation and expression of analysis results
9 Test report
Annex A (Normative) Flow chart of procedure for acceptance of specimen analysis results
