GB/T 11926-2025 Determination of phosphorus in uranium dioxide powder and pellets—Molybdenum blue spectrophotometric method English, Anglais, Englisch, Inglés, えいご
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ICS 27. 120 CCS F 46
GB/T 11926-2025 replaces GB/T 11926-1989
Determination of phosphorus in uranium dioxide powder and pellets—Molybdenum blue spectrophotometric method
Issued on 2025-08-29 Implemented on 2025-08-29
Issued by State Administration for Market Regulation Standardization Administration of China
Contents
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Ascorbic acid-molybdenum blue spectrophotometric method
5 Bismuth salt-ascorbic acid-molybdenum blue spectrophotometric method
6 Test data processing
7 Precision
8 Test report
Determination of phosphorus in uranium dioxide powder and pellets—Molybdenum blue spectrophotometric method
1 Scope
This document describes the molybdenum blue spectrophotometric method for determining phosphorus content in uranium dioxide powder and pellets. This document is applicable to the determination of phosphorus in uranium dioxide powder and pellets, and may also be referenced for the determination of phosphorus in other uranium oxides such as triuranium octoxide. The determination range of this document is 10 μg/g to 300 μg/g, with allowable impurity contents of Co 0.2 mg/g; Ni 0.4 mg/g; Fe, Mn, Cr, Sn, Cu, V, W, Si, Ti, F, Zn all 0.5 mg/g.
2 Normative references
This document does not contain any normative references.
3 Terms and definitions
This document does not require any terms and definitions to be defined.
4. Ascorbic acid molybdenum blue spectrophotometric method
4.1 Principle
The sample is dissolved in hydrochloric acid hydrogen peroxide or nitric acid perchloric acid. In the hydrochloric acid medium, the phosphorus in the sample reacts with ammonium molybdate to form phosphomolybdic yellow heteropolyacid, which is then reduced to phosphomolybdic blue heteropolyacid by ascorbic acid. The absorbance of phosphomolybdic blue is measured at a wavelength of 650 nm. Measure the phosphorus content in the sample using the standard curve method.
4.2 Reagents or materials
Unless otherwise specified, the reagents used in the analysis are high-quality pure reagents that meet national standards, and the water used for analysis has a conductivity (25 ℃) not greater than 0 10 mS/m of deionized water.
4.2. 1 Hydrochloric acid: ρ (HCl)=1.19g/mL.
4.2.5 Ascorbic acid solution: ρ (C6 H8 O6)=10 g/L.
4.2.6 Phosphorus standard reserve solution.
4.3 Instruments and equipment
4.3. 1. Spectrophotometer: The wavelength range is 300 nm to 800 nm.
4.3.2 Electric heating plate: The maximum temperature shall not be lower than 250 ℃.
4.3.3 Electronic balance: The division value is 0 1 mg。
4.3.4 Coloring dish: 2 cm.
4.3.5 Water bath device.
4.4 Samples
4.4. Sample preparation
4.4. one The particle size of the uranium dioxide pellet sample after crushing is not greater than 154 μ m.
4.4. 1.2 Direct sampling and analysis of uranium dioxide powder.
