YS/T 273.12-2024 English PDFYS/T 273.12: Historical versions
Basic dataStandard ID: YS/T 273.12-2024 (YS/T273.12-2024)Description (Translated English): (Chemical analysis methods and physical property determination methods of cryolite - Part 12: Determination of calcium oxide content - Flame atomic absorption spectrometry) Sector / Industry: Nonferrous Metallurgy Industry Standard (Recommended) Classification of Chinese Standard: H30 Classification of International Standard: 71.100.10 Date of Issue: 2024-10-24 Date of Implementation: 2025-05-01 Older Standard (superseded by this standard): YS/T 273.12-2006 Issuing agency(ies): Ministry of Industry and Information Technology Summary: This standard specifies the method for determining the calcium oxide content in cryolite by flame atomic absorption spectrometry. This standard is applicable to the determination of calcium oxide content in cryolite, and the determination range is 0.0050% to 3.00%. YS/T 273.12-2006
YS
NONFERROUS METAL INDUSTRY STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
ICS 71.100.10
H 21
Chemical analysis methods and physical properties of
cryolite - Part 12: The atomic absorption
spectrophotometric method for the determination of calcium
oxide content
ISSUED ON: MAY 25, 2006
IMPLEMENTED ON: DECEMBER 1, 2006
Issued by: National Development and Reform Commission of PRC
Table of ContentsForeword ... 3 1 Scope ... 5 2 Method summary ... 5 3 Reagents ... 5 4 Instruments and apparatuses ... 6 5 Test sample ... 6 6 Analytical procedure ... 7 7 Calculation of analysis result ... 8 8 Precision ... 8 9 Quality assurance and control ... 9 Chemical analysis methods and physical properties of cryolite – Part 12: The atomic absorption spectrophotometric method for the determination of calcium oxide contentScopeThis Part specifies the method for determination of calcium oxide content in cryolite. This Part applies to the determination of calcium oxide in cryolite. Determination range (mass fraction): ≤1.25%. 2 Method summary Use perchloric acid to de-fluorinate the test portion; heat until the smoke of perchloric acid has evaporated, then use hydrochloric acid and water to dissolve it. In the presence of lanthanum chloride, measure the calcium content using an air-acetylene fuel-rich flame at the wavelength of 422.7 nm of the atomic absorption spectrometer. 3 Reagents 3.1 Perchloric acid (ρ1.67 g/mL). 3.2 Hydrochloric acid (1+1): guaranteed reagent. 3.3 Sodium solution (7.5 mg/mL): Transfer 9.5 g of high-purity sodium chloride and use water to dissolve it in a 500 mL volumetric flask. 3.4 Sodium solution (1.5 mg/mL): Transfer 20 mL of sodium solution (3.3) into a 100 mL volumetric flask; use water to dilute to the mark; mix well. 3.5 Lanthanum chloride solution (200 g/L): Take 100 g of LaCl3·nH2O; use water to dilute it in a 500 mL volumetric flask. 3.6 Aluminum solution (4 mg/mL): Weigh 4.00 g of pickled high-purity aluminum; place it in a 500 mL beaker; cover the watch plate; add a total of 120 mL of hydrochloric acid (3.2) in batches; add a drop of mercury to help dissolution; after the violent reaction stops, slowly heat until it is completely dissolved; cool; transfer the solution to a 1 000 mL volumetric flask; use water to dilute to the mark; mix well. 3.7 Aluminum solution (0.8 mg/mL): Pipette 20 mL of aluminum solution (3.6) into a 100 mL volumetric flask; use water to dilute to the mark; mix well. 3.8 Calcium standard stock solution: Weigh 1.248 6 g of calcium carbonate that has been previously dried at 105 °C; place it in a 250 mL beaker; cover it with a watch plate; add 50 mL of water; then add 10 mL of hydrochloric acid (3.2); heat slightly; after the reaction is complete, cool; transfer to a 500 mL volumetric flask; use water to dilute to the mark; mix well. 1 mL of this solution contains 1.00 mg of calcium. 3.9 Calcium standard solution: Pipette 25.00 mL of calcium standard stock solution (3.8) into a 500 mL volumetric flask; use water to dilute to the mark; mix well. 1 mL of this solution contains 0.05 mg of calcium. 4 Instruments and apparatuses Atomic absorption spectrometer, hollow cathode lamp with calcium. Under the best working conditions of the instrument, anything that can achieve the following indicators can be used: - Characteristic concentration: In a solution consistent with the matrix of the measured sample, the characteristic concentration of calcium shall not be greater than 0.24 ug/mL. - Precision: Use the standard solution of the highest concentration to measure the absorbance for 10 times, where the standard deviation shall not exceed 1.0% of the average absorbance. Use the standard solution of the lowest concentration (not the “zero” concentration standard solution) to measure the absorbance for 10 times, where the standard deviation shall not exceed 0.5% of the average absorbance of the standard solution of the highest concentration. - Linearity of working curve: Divide the working curve into five segments according to the concentration, and the ratio of the absorbance difference of the highest segment to the absorbance difference of the lowest segment shall not be less than 0.7. 5 Test sample The test sample shall comply with the requirements of 3.3 in YS/T 273.13. ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of YS/T 273.12-2024_English be delivered?Answer: Upon your order, we will start to translate YS/T 273.12-2024_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 YS/T 273.12-2024_English with my colleagues?Answer: Yes. The purchased PDF of YS/T 273.12-2024_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 Sales@ChineseStandard.net. 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 YS/T 273.12-2024?Answer: Yes. Unless special scenarios such as technical constraints or academic study, you should always prioritize to purchase the latest version YS/T 273.12-2024 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. |