Analytical methods for fissionable materials in the nuclear fuel cycle. Covering June 1974--June 1975

Abstract

REFERENCES i4It* I.I.J S,,,n "",-,1,, nl"TT, ? ANALYTICAL METHODS FOR FISSIONABLE MATERIALS IN THE NUCLEAR FUEL CYCLECompiled by Glenn R. Waterbury ABSTRACT Progress continued on method development for the dissolution of difficult-to-dissolve materials, the automated analysis of plutonium and uranium, the preparation of plutonium materials for the Safeguard Analytical Laboratory Evaluation (SALE) Program, and the analysis of HTGR fuel and SALE uranium materials. The previously developed Teflon-container, metal-shell apparatus was applied to the dissolution of various nuclear materials. Gas-solid reactions, mainly using chlorine at elevated temperatures, are promising for separating uranium from refractory compounds. An automated spectrophotometer designed for determining plutonium and uranium has been tested successfully by the New Brunswick Laboratory. Procedures were developed for this instrument to analyze uranium-plutonium mixtures and the effects of diverse ions upon the analysis of plutonium and uranium were further established. A versatile apparatus was assembled to develop electrotitrimetric methods that will serve as *he basis for precise automated determinations of plutonium. Progress with the first of these methods is reported. Plutonium materials prepared for the SALE Program were plutonium oxide, uranium-plutonium mixed oxide, and plutonium metal. Improvements were made in the methods used for determining uranium in HTGR fuel materials and SALE uranium materials. Plutonium metal samples were 'prepared, characterized, and distributed, and half-life measurements were in progress as part of an inter-ERDAlaboratory program to measure accuracy the half-lives of longlived plutonium isotopes.

Analytical methods for fissionable material determinations in the nuclear fuel cycle. Progress report, October 1, 1976--September 30, 1977

“…These conditions were applied to New Brunswick Laboratory (NBL)-supplied scrap containing zirconium, previously found very resistant to mineral acid dissolution even in the Teflon-container, metal-shell apparatus. 1 Over 95% of the uranium and 40% of the 1-g sample volatilized in 8 h at 1000°C or in 4 h at 1200°C at 1.2-atm chlorine pressure. At 1200°C, the quartz tube deteriorated and had to be replaced after 25 h.…”

“…1 We investigated this reaction for use on nuclear fuel cycle materials. It proved cumbersome and offered no substantial advantages over more conventional dissolution techniques.…”

Evaluation of the LASL automated spectrophotometer for uranium determination at submilligram levels

“…To extend the applicability of the automated spectrophotometer, we are currently adapting another uranium spectrophotometric method that has sensitivity to low microgram levels. 2 Meanwhile, the need to analyze samples from various uranium recovery processes in which the concentrations of uranium generally are within the range of 0.05 to 1 nig/mi prompted an evaluation of the instrument, without chemical or instrumental modifications, for lower level uranium analyses. This evaluation consisted of a 15-day processing of standard solutions containing 0.12 to 1.5 mg of uranium as well as the analysis of 32 uranium samples from a recovery process.…”