Tentative method for colorimetric determination of technetium in aqueous solutions

Book · Mon Jan 01 04:00:00 EST 1973

OSTI ID:4372069

Quantitative determination of technetium in known volumes of aqueous solutions of nuclear fuel that contain radioactive nuclides is described. These solutions are from the processing of irradiated nuclear fuel and from the laboratory studies on irradiated nuclear fuel. The method is applicable to solutions that contain a minimum of 5 mu g of technetium per sample, but it will detect as little as 0.4 mu g. The method as described is limited to simple volumes of 2 ml or less, but reagent volumes can be scaled to accommodate larger sample aliquots. This method is based on measurement of the absorbance of the technetium thiocyanate complex in chloroform. All the technetium in the measured volume of sample is first oxidized to technetium (VII) by basic hydrogen peroxide. The alkalinity of the solution must be between 2.6 and 3.5 M for quantitative extraction of the technetium-tetrapropyl ammonium ion-association complex into the chloroform solvent. Color development is made in the chloroform phase with the addition of strong sulfuric acid, tetrapropylammonium hydroxide, and potassium thiocyanate. The colored complex absorbs at 513 nm, has a molar extinction coefficient of 46,000, and is stable for several hours. The concentration of technetium in the sample is determined from two comparison standards bracketing the unknown and processed concurrently, or from a standard curve. (LK)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-29-007533
• OSTI ID: 4372069
• Report Number(s): ASTM-E--417-70-T
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*TECHNETIUM-- ABSORPTION SPECTROSCOPY
AQUEOUS SOLUTIONS
CHLOROFORM
N40120* --Chemistry--Analytical & Separations Chemistry-- Chemical & Spectral Procedures
N40421 --Chemistry--Radiochemistry & Nuclear Chemistry--Reactor Fuels
NUCLEAR FUELS
PH VALUE
QUANTITATIVE CHEMICAL ANALYSIS
REPROCESSING
SPENT FUELS
THIOCYANATES