ISO 12183:2016 describes an analytical method for the electrochemical assay of pure plutonium nitrate solutions of nuclear grade, with a total uncertainty not exceeding ±0,2 % at the confidence level of 0,95 for a single determination (coverage factor, K = 2). The method is suitable for aqueous solutions containing more than 0,5 g/L plutonium and test samples containing between 4 mg and 15 mg of plutonium. Application of this technique to solutions containing less than 0,5 g/L and test samples containing less than 4 mg of plutonium requires experimental demonstration by the user that applicable data quality objectives will be met. For some applications, purification of test samples by anion exchange is required before measurement to remove interfering substances when present in significant amounts.
Tämän julkaisun valmistelusta Suomessa vastaa Metalliteollisuuden Standardisointiyhdistys ry, puh. 09 19 231 (vaihde).
Sisällysluettelo
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents
6 Apparatus
7 Procedure
7.1 Plutonium determination
7.2 Analysis of subsequent test samples
8 Expression of results
8.1 Calculation of the electrical calibration factor
8.2 Calculation of the blank
8.3 Fraction of electrolysed plutonium
8.4 Plutonium content
8.5 Quality control
9 Characteristics of the method
9.1 Repeatability
9.2 Confidence interval
9.3 Analysis time
10 Interferences
11 Procedure variations and optimization
11.1 Accountability measurements and reference material preparation
11.2 Process control measurements
11.3 Measurement cell design
11.4 Electrolyte and electrode options
11.5 Test sample size
11.6 Background current corrections
11.7 Correction for iron
11.8 Control-potential adjustment
11.9 Calibration methodologies
Annex A Purification by anion-exchange separation (normative)
Annex B Determination of formal potential, E0 (normative)