|
US$189.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email.
GB/T 20975.7-2020: Methods for chemical analysis of aluminium and aluminium alloys - Part 7: Determination of manganese content
Status: Valid GB/T 20975.7: Evolution and historical versions
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Standard Title (Description) | Status | PDF |
| GB/T 20975.7-2020 | English | 189 |
Add to Cart
|
3 days [Need to translate]
|
Methods for chemical analysis of aluminium and aluminium alloys - Part 7: Determination of manganese content
| Valid |
GB/T 20975.7-2020
|
| GB/T 20975.7-2008 | English | 399 |
Add to Cart
|
3 days [Need to translate]
|
Methods for chemical analysis of aluminium and aluminium alloys -- Potassium periodate spectrophotometric method
| Obsolete |
GB/T 20975.7-2008
|
PDF similar to GB/T 20975.7-2020
Basic data | Standard ID | GB/T 20975.7-2020 (GB/T20975.7-2020) | | Description (Translated English) | Methods for chemical analysis of aluminium and aluminium alloys - Part 7: Determination of manganese content | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | H12 | | Classification of International Standard | 77.120.10 | | Word Count Estimation | 10,115 | | Date of Issue | 2020-06-02 | | Date of Implementation | 2021-04-01 | | Older Standard (superseded by this standard) | GB/T 20975.7-2008 | | Quoted Standard | GB/T 8005.2; GB/T 8170-2008 | | Issuing agency(ies) | State Administration for Market Regulation, China National Standardization Administration | | Summary | This standard specifies the potassium periodate spectrophotometric method and the Na2EDTA titration method for the determination of manganese content in aluminum and aluminum alloys. This standard applies to the arbitration determination of manganese content in aluminum and aluminum alloys. Determination range of potassium periodate spectrophotometry: 0.004 0%��2.00%; Determination range of Na2EDTA titration method: 8.50%��45.00%. The potassium periodate spectrophotometry in this standard is not applicable to aluminum and aluminum alloys with a mass fraction of cerium > 0.005%. | GB/T 20975.7-2020: Methods for chemical analysis of aluminium and aluminium alloys - Part 7: Determination of manganese content
---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Methods for chemical analysis of aluminium and aluminium alloys--Part 7.Determination of manganese content
ICS 77.120.10
H12
National Standards of People's Republic of China
Replace GB/T 20975.7-2008
Chemical analysis methods of aluminum and aluminum alloys
Part 7.Determination of Manganese Content
2020-06-02 released
Implementation on 2021-04-01
State Administration for Market Regulation
Issued by the National Standardization Management Committee
Foreword
GB/T 20975 "Methods for Chemical Analysis of Aluminum and Aluminum Alloys" is divided into 37 parts.
---Part 1.Determination of mercury content;
---Part 2.Determination of arsenic content;
---Part 3.Determination of copper content;
---Part 4.Determination of iron content;
---Part 5.Determination of silicon content;
---Part 6.Determination of cadmium content;
---Part 7.Determination of manganese content;
---Part 8.Determination of zinc content;
---Part 9.Determination of lithium content by flame atomic absorption spectrometry;
---Part 10.Determination of tin content;
---Part 11.Determination of lead content;
---Part 12.Determination of titanium content;
---Part 13.Determination of vanadium content;
---Part 14.Determination of nickel content;
---Part 15.Determination of boron content;
---Part 16.Determination of magnesium content;
---Part 17.Determination of strontium content;
---Part 18.Determination of chromium content;
---Part 19.Determination of Zirconium Content;
---Part 20.Determination of Gallium Content Butyl Rhodamine B Spectrophotometry;
---Part 21.Determination of calcium content;
---Part 22.Determination of beryllium content;
---Part 23.Determination of antimony content;
---Part 24.Determination of total rare earth content;
---Part 25.Determination of element content by inductively coupled plasma atomic emission spectrometry;
---Part 26.Determination of carbon content by infrared absorption method;
---Part 27.Determination of cerium, lanthanum and scandium content by inductively coupled plasma atomic emission spectrometry;
---Part 28.Determination of cobalt content by flame atomic absorption spectrometry;
---Part 29.Determination of molybdenum content thiocyanate spectrophotometric method;
---Part 30.Determination of hydrogen content by heating extraction thermal conductivity method;
---Part 31.Determination of phosphorus content molybdenum blue spectrophotometric method;
---Part 32.Determination of Bismuth Content;
---Part 33.Determination of potassium content by flame atomic absorption spectrometry;
---Part 34.Determination of sodium content by flame atomic absorption spectrometry;
---Part 35.Determination of tungsten content by flame atomic absorption spectrometry;
---Part 36.Determination of silver content by flame atomic absorption spectrometry;
--- Part 37.Determination of Niobium Content.
This part is Part 7 of GB/T 20975.
This section was drafted in accordance with the rules given in GB/T 1.1-2009.
This Part replaces GB/T 20975.7-2008 "Methods for Chemical Analysis of Aluminum and Aluminum Alloys Part 7.Determination of Manganese Content, Periodic Acid
Compared with GB/T 20975.7-2008, Potassium Spectrophotometry, except for editorial changes, the main technical changes are as follows.
--- Added standard use safety warnings;
--- Added "Normative Reference Documents" (see Chapter 2);
--- Added "Terms and Definitions" (see Chapter 3);
---Added requirements for reagents and water used in analysis (see 4.2, 5.2);
---Modified the precision of the potassium periodate spectrophotometric method (see 4.7, Chapter 8 of the.2008 edition);
--- Added "Na2EDTA Titration Method" (see Chapter 5);
--- Deleted "Quality Assurance and Control" (see Chapter 9 of the.2008 edition);
--- Added "Test Report" (see Chapter 6).
This part was proposed by China Nonferrous Metals Industry Association.
This part is under the jurisdiction of the National Nonferrous Metals Standardization Technical Committee (SAC/TC243).
Drafting organizations of this section. Northeast Light Alloy Co., Ltd., Non-ferrous Metal Technology and Economic Research Institute, Guizhou Province Analysis and Testing Research Institute, China
Aluminum Material Application Research Institute Co., Ltd., Hebei Sitong New Metal Materials Co., Ltd., Guangxi Liuzhou Yinhai Aluminum Co., Ltd.,
Shandong Nanshan Aluminum Co., Ltd., Xi'an Hantang Analysis and Testing Co., Ltd., Shandong Yankuang Light Alloy Co., Ltd., Guangdong Guanglv Aluminum Profile
Limited, China Aluminum Ruimin Co., Ltd.
The main drafters of this section. Liu Shuangqing, Wang Jinhua, Xi Huan, Wang Guojun, Liu Yungui, He Minglan, Wang Wenhong, Zhang Wei, Xu Sheng, Liu Houyong,
Li Yonghui, Chuang Hongyu, Liu Chang, Wu Yun, Su Yulong, Gao Xinyu, Qi Yanhua, Zhou Bing.
The previous versions of the standards replaced by this part are as follows.
---GB/T 6987.7-1986, GB/T 6987.7-2001;
---GB/T 20795.7-2008.
Chemical analysis methods of aluminum and aluminum alloys
Part 7.Determination of Manganese Content
Warning---Personnel using this section should have practical experience in formal laboratory work. This section does not point out all possible safety issues
question. The user is responsible for taking appropriate safety and health measures and ensuring compliance with the conditions stipulated by relevant national laws and regulations.
1 Scope
This part of GB/T 20975 specifies the potassium periodate spectrophotometric method and Na2EDTA titration method to determine the manganese content in aluminum and aluminum alloys.
This section applies to the arbitration determination of manganese content in aluminum and aluminum alloys. Potassium periodate spectrophotometric determination range. 0.0040%~
2.00%; Na2EDTA titration method determination range. 8.50%~45.00%.
The potassium periodate spectrophotometric method in this section is not applicable to aluminum and aluminum alloys with a cerium mass fraction > 0.005%.
2 Normative references
The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this article
Pieces. For undated references, the latest version (including all amendments) applies to this document.
GB/T 8005.2 Terminology of Aluminum and Aluminum Alloy Part 2.Chemical Analysis
GB/T 8170-2008 Numerical rounding rules and the expression and determination of limit values
3 Terms and definitions
The terms and definitions defined in GB/T 8005.2 apply to this document.
4 Potassium periodate spectrophotometry
4.1 Method summary
The sample was dissolved with sodium hydroxide, acidified with sulfuric acid and nitric acid, and oxidized with potassium periodate to develop color in the presence of phosphoric acid. At spectrophotometer wavelength
The absorbance was measured at 525.0nm to determine the manganese content.
4.2 Reagents
Unless otherwise stated, only reagents and laboratory secondary water confirmed to be analytically pure are used in the analysis.
4.2.1 Sulfuric acid (ρ=1.84g/mL).
4.2.2 Phosphoric acid (ρ=1.69g/mL).
4.2.3 Nitric acid (ρ=1.42g/mL).
4.2.4 Hydrofluoric acid (ρ=1.14g/mL).
4.2.5 Sulfuric acid (1 1).
4.2.6 Sodium hydroxide solution (200g/L).
4.2.7 Fluoroboric mixed acid. Put 800mL of boric acid solution saturated at 20℃ and.200mL of hydrofluoric acid (4.2.4) in a plastic bottle
Mix well.
4.2.8 Potassium periodate solution (50g/L). Weigh 5g potassium periodate and dissolve in water, add 20mL nitric acid (4.2.3), and dilute with water to
100mL, mix well.
4.2.9 Sodium nitrite solution (20g/L).
4.2.10 Sodium sulfite solution (10g/L). Weigh 1g sodium sulfite, add sulfuric acid (1 20) to dissolve completely, and dilute with sulfuric acid (1 20) to
100mL, mix well.
4.2.11 Water without reducing agent. Add 10mL sulfuric acid (4.2.5) to each liter of water to acidify and boil, add a small amount of potassium periodate, and continue to boil
About 10min, set aside after cooling.
4.2.12 Manganese standard storage solution. use a certified standard solution for preparation first. Or weigh 1.000g manganese (wMn≥99.99%) in a beaker,
Add 20mL sulfuric acid (4.2.5), about 80mL water, heat to dissolve and boil for 3min, cool, transfer to a 1000mL volumetric flask,
Dilute to the mark with water and mix well. This solution 1mL contains 1mg manganese.
4.2.13 Manganese standard solution. Pipette 50.00mL manganese standard stock solution (4.2.12) into a 1000mL volumetric flask and dilute to the mark with water.
Mix well. This solution 1mL contains 0.05mg manganese.
4.4 Sample
Process the sample into chips with a thickness of not more than 1mm.
4.5 Analysis steps
4.5.1 Sample
According to Table 1, weigh the sample (4.4) of the corresponding mass (m0) to the nearest 0.0001g.
4.5.2 Parallel test
Do two tests in parallel and take the average value.
4.5.3 Blank test
Do a blank test with the sample. In a 250mL beaker, add 8mL nitric acid (4.2.3), 12mL sulfuric acid (4.2.5), and evaporate to dryness
(Be careful not to burn). Dissolve the residue with a small amount of warm water, add 2mL nitric acid (4.2.3), 18mL sulfuric acid (4.2.5), 40mL sodium hydroxide
Solution (4.2.6), mix well, heat until the solution is clear, dilute to about 65mL with water, and proceed according to 4.5.4.3.When the aluminum alloy sample contains silicon
When the mass fraction is >10.0% and the mass fraction of manganese is < 0.040%, follow the steps below. In a 250mL beaker, add 8mL nitric acid
(4.2.3), 12mL sulfuric acid (4.2.5), evaporate to dryness (be careful not to burn), dissolve the residue with a small amount of warm water. Add 2mL nitric acid
(4.2.3), 8mL sulfuric acid (4.2.5), dilute with water to about 60mL, add 2mL fluoroboric acid (4.2.7), dilute with water to about 65mL,
The following shall be carried out according to 4.5.4.3.
4.5.4 Determination
4.5.4.1 Place the sample (4.5.1) in a platinum (or nickel) dish, add a total of 40 mL of sodium hydroxide solution (4.2.6) in portions, and cover with platinum (or nickel).
Nickel) watch dish, after violent reaction, heat to dissolve and evaporate to a paste, slightly cold. Use as little warm water as possible to wash the cup wall and watch dishes.
Dissolve. Carefully transfer the sample solution into a 250mL beaker containing 30mL sulfuric acid (4.2.5) and 10mL nitric acid (4.2.3) in advance;
If there is a precipitate of manganese hydroxide adhered to the wall of the platinum (or nickel) cup, dissolve it with a small amount of slightly boiling sodium sulfite solution (4.2.10), and combine the solution with the sample
In the solution, wash the platinum (or nickel) dish with warm water, heat the sample solution to clear and cool.
4.5.4.2 When the mass fraction of manganese is 0.0040%~0.040%, add acid according to Table 1, and heat and concentrate the sample solution to about
65mL. When the mass fraction of manganese is >0.040%~2.00%, transfer the sample solution (4.5.4.1) into the corresponding volumetric flask (V0) according to Table 1.
Dilute to the mark with water and mix well; pipette the corresponding volume (V1) of the sample solution into a 250mL beaker, add the corresponding amount of acid, and dilute to approximately
65mL.
4.5.4.3 When the mass fraction of silicon in the aluminum alloy sample is> 10% and the mass fraction of manganese is < 0.04%, use the following operations instead of 4.5.4.1 and
4.5.4.2.Place the sample (4.5.1) in a 250mL beaker, add 20mL sulfuric acid (4.2.5), 10mL nitric acid (4.2.3), 2mL fluoroboron
Mix the acid (4.2.7), cover with a watch glass, heat slightly until the sample is completely dissolved, and heat to boiling to remove nitrogen oxides. Dilute with warm water to about 50mL, add
Pour a small amount of filter paper pulp, heat for several minutes, filter with slow filter paper, wash with warm water, and collect the filtrate in a 250mL beaker. Filter the residue together
The paper is placed in a platinum crucible and completely ashed at 500℃~600℃ (do not burn the filter paper), and cool. Add a few drops of sulfuric acid (4.2.1), 2mL~
5mL hydrofluoric acid (4.2.4), add nitric acid (4.2.3) dropwise until the solution is clear, evaporate to dryness, burn at 700°C for several minutes, and cool. Add a few drops
Dissolve the residue in a small amount of warm water with sulfuric acid (4.2.5) and heat it until it is completely dissolved (filter if necessary). Incorporate this solution into the sample solution and concentrate to
About 65mL.
4.5.4.4 Add 5mL phosphoric acid (4.2.2), heat the sample solution to boiling, add 10mL potassium periodate solution (4.2.8), continue to boil until
After the red color appears, continue to add water without reducing agent (4.2.11) to keep the volume of the sample solution unchanged, then boil for another 15 minutes~
30min, heat preservation for 15min~20min, and cool. Transfer the sample solution into 100 mL rinsed with water without reducing agent (4.2.11) in advance
In a volumetric flask, dilute to the mark with water (4.2.11) without reducing agent and mix well.
4.5.4.5 Transfer part of the sample solution (4.5.4.4) and blank test solution (4.5.3) into the corresponding absorption tank, and use water without reducing agent.
(4.2.11) is the reference, and the absorbance (A1, A3) is measured at the wavelength of 525.0nm in the spectrophotometer. The remaining solution in the volumetric flask
Add 2 drops of sodium nitrite solution (4.2.9) and mix to make the permanganic acid fade, and measure the absorbance (A2, A4). According to the absorption of manganese in the solution
Luminosity (A), find the corresponding manganese mass (m1) from the working curve.
4.5.4.6 Calculate the absorbance A of manganese in the solution according to formula (1).
4.5.5 Drawing of working curve
4.5.5.1 Pipette 0mL, 0.80mL, 2.00mL, 4.00mL, 6.00mL, 8.00mL, 10.00mL manganese standard solution (4.2.13) in
In a set of 250mL beakers, add 15mL sulfuric acid (4.2.5), 10mL nitric acid (4.2.3), 5mL phosphoric acid (4.2.2), and dilute with water.
Release to about 70mL, heat to boiling. Add 10mL potassium periodate solution (4.2.8), continue to boil until red appears, continue to add
While keeping the volume of the original water (4.2.11) unchanged, boil it for another 15-30 minutes, keep it warm for 15-20 minutes, and cool. Will melt
The liquid is transferred into a set of 100 mL volumetric flasks rinsed with water without reducing agent (4.2.11), and diluted with water without reducing agent (4.2.11) to
Scale and mix well.
4.5.5.2 Move part of the series of standard solutions (4.5.5.1) and reagent blank solution (without manganese standard solution) into the corresponding absorption pool to
Water without reducing agent (4.2.11) is the reference, and the absorbance (A5, A7) is measured at the wavelength of 525.0nm in the spectrophotometer. Volumetric flask
Add 2 drops of sodium nitrite solution (4.2.9) to the remaining test solution and mix to make the permanganic acid fade, and measure the absorbance (A6, A8) respectively. Manganese
The amount is the abscissa, the solution absorbance (A) is the ordinate, and the working curve is drawn.
4.5.5.3 Calculate the absorbance A of manganese in the solution according to formula (2).
4.6 Test data processing
4.7 Precision
4.7.1 Repeatability
The measured values of two independent test results obtained under repeatability conditions, within the average range given below, these two test results
The absolute difference does not exceed the repeatability limit r, and the case of exceeding the repeatability limit r does not exceed 5%. The repeatability limit r is within the linear range according to the data in Table 2.
Obtained by interpolation or extension method.
4.7.2 Reproducibility
The measured values of two independent test results obtained under reproducibility conditions, within the average range given below, the two test results
The absolute difference does not exceed the reproducibility limit R, and the case of exceeding the reproducibility limit R does not exceed 5%. Reproducibility limit R According to the data in Table 3, the linear internal
Obtained by interpolation or extension method.
5 Na2EDTA titration method
5.1 Method summary
In a weakly acidic solution, manganese is complexed with an excess of Na2EDTA standard titration solution. Use xylenol orange as indicator, titrate with zinc standard
The solution was titrated with the remaining Na2EDTA standard titration solution to orange-red color to determine the manganese content.
5.2 Reagents
Unless otherwise stated, only reagents and laboratory tertiary water confirmed to be analytically pure are used in the analysis.
5.2.1 Ammonia (ρ=0.90g/mL).
5.2.2 Mixed acid. 300mL hydrochloric acid (1 1) and 50mL nitric acid (1 1) mix well.
5.2.3 Hydrochloric acid (1 1).
5.2.4 hexamethylenetetramine solution (300g/L).
5.2.5 Sodium hydroxide solution (150g/L).
5.2.7 Thiourea solution (100g/L).
5.2.8 Hydroxylamine hydrochloride solution (100g/L).
5.2.9 Sodium hydroxide solution (10g/L).
5.2.10 Zinc standard titration solution (c0=0.025mol/L). Weigh 1.6348g zinc (wZn≥99.99%), add 30mL hydrochloric acid
(5.2.3) Heat to dissolve completely, cool, transfer to a 1000mL volumetric flask, dilute to the mark with water, and mix.
5.2.11 Disodium ethylenediaminetetraacetic acid (Na2EDTA) standard titration solution (c1≈0.05mol/L).
---Preparation. Weigh 18.61g disodium ethylenediaminetetraacetic acid (Na2EDTA) in a beaker, add 500mL water, heat to dissolve completely,
Cool, filter in a 1000mL volumetric flask, dilute to the mark with water, and mix.
---Calibration. Pipette volume (V2) of 30.00mL zinc standard titration solution (5.2.10) into a 400mL conical beaker, add 50mL
Water, 10mL hexamethylenetetramine solution (5.2.4), 2 drops of xylenol orange solution (5.2.12), use Na2EDTA standard titration solution
(5.2.11) Titrate until the solution is bright yellow as the end point, record the consumption of Na2EDTA standard titration solution volume (V3).
---Calculation. Calculate the concentration c1 of the Na2EDTA standard titration solution according to formula (4).
5.2.12 Xylenol orange solution (5g/L).
5.2.13 p-nitrophenol solution (2g/L).
5.3 Specimen
Process the sample into chips with a thickness of not more than 1mm.
5.4 Analysis steps
5.4.1 Sample
Weigh the sample (5.3) with a mass (m) of 0.50g to the nearest 0.0001g.
5.4.2 Parallel test
Do two tests in parallel and take the average value.
5.4.3 Determination
5.4.3.1 Place the sample (5.4.1) in a 400mL beaker, slowly add 30mL of sodium hydroxide solution (5.2.5), and heat until the sample is dissolved
Complete, dilute with water to about 100mL boil, filter with medium-speed quantitative filter paper. Wash the precipitate 2 times with sodium hydroxide solution (5.2.9)~
3 times, then wash the precipitate with hot water 5 to 6 times, and discard the filtrate.
5.4.3.2 Add a total of 30 mL of hot mixed acid (5.2.2) to the funnel in batches, dissolve the precipitate in the original beaker, and wash the precipitate with hot water.
Filter paper, cool, transfer the filtrate into a 100mL volumetric flask (V4), dilute to the mark with water, and mix.
5.4.3.3 Pipette volume (V5) of 20.00mL sample solution (5.4.3.2) into a conical beaker, add 25mL ammonium fluoride solution (5.2.6),
3mL thiourea solution (5.2.7), 7mL hydroxylamine hydrochloride solution (5.2.8), 2 drops of p-nitrophenol solution (5.2.13), neutralized with ammonia (5.2.1)
Yellow, then adjust to colorless with hydrochloric acid (5.2.3) and excess 4 drops. Add 40mL hexamethylenetetramine solution (5.2.4), volume (V6) is
20.00mL Na2EDTA standard titration solution (5.2.11), 2 drops of xylenol orange solution (5.2.12), use zinc standard titration solution (5.2.10)
Titrate to orange-red as the end point. Record the volume of the zinc standard titration solution (V7).
Note. When approaching the end point, the titration speed should be slow. After the test solution is orange-red, continue to vibrate for more than 10 seconds until the red color does not fade.
5.5 Test data processing
The manganese content is calculated as the mass fraction wMn of manganese, calculated according to formula (5).
5.6 Precision
5.6.1 Repeatability
The measured values of two independent test results obtained under repeatability conditions, within the average range given below, these two test results
The absolute difference does not exceed the repeatability limit r, and the case of exceeding the repeatability limit r does not exceed 5%. The repeatability limit r is within the linear range according to the data in Table 4
Obtained by interpolation or extension method.
5.6.2 Reproducibility
The measured values of two independent test results obtained under reproducibility conditions, within the average range given below, the two test results
The absolute difference does not exceed the reproducibility limit R, and the case of exceeding the reproducibility limit R does not exceed 5%. Reproducibility limit R is linear within
Obtained by interpolation or extension method.
Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 20975.7-2020_English be delivered?Answer: Upon your order, we will start to translate GB/T 20975.7-2020_English as soon as possible, and keep you informed of the progress. The lead time is typically 1 ~ 3 working days. The lengthier the document the longer the lead time. Question 2: Can I share the purchased PDF of GB/T 20975.7-2020_English with my colleagues?Answer: Yes. The purchased PDF of GB/T 20975.7-2020_English will be deemed to be sold to your employer/organization who actually pays for it, including your colleagues and your employer's intranet. Question 3: Does the price include tax/VAT?Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs): List of DTAs signed between Singapore and 100+ countriesQuestion 4: Do you accept my currency other than USD?Answer: Yes. If you need your currency to be printed on the invoice, please write an email to [email protected]. In 2 working-hours, we will create a special link for you to pay in any currencies. Otherwise, follow the normal steps: Add to Cart -- Checkout -- Select your currency to pay. Question 5: Should I purchase the latest version GB/T 20975.7-2020?Answer: Yes. Unless special scenarios such as technical constraints or academic study, you should always prioritize to purchase the latest version GB/T 20975.7-2020 even if the enforcement date is in future. Complying with the latest version means that, by default, it also complies with all the earlier versions, technically.
|