ASTM C 1168:2023

1.1 This practice is a compilation of dissolution techniques for plutonium materials that are applicable to the test methods used for characterizing these materials. Dissolution treatments for the major plutonium materials assayed for plutonium or analyzed for other components are listed. Aliquots of the dissolved materials are dispensed on a mass basis when one of the analyses must be of high precision, such as plutonium assay; otherwise they are dispensed on a volume basis. 1.2 Procedures in this practice are intended for the dissolution of plutonium metal, plutonium oxide, and uranium-plutonium mixed oxides. Aliquots of dissolved materials are analyzed using test methods, such as those developed by Subcommittee C26.05 on Methods of Test, to demonstrate compliance with applicable requirements. These may include product specifications such as Specifications C757 and C833 . 1.3 One or more of the procedures in this practice may be applicable to unique plutonium materials, such as alloys, compounds, and scrap materials. The user must determine the applicability of this practice to such materials. 1.4 The treatments, in order of presentation, are as follows: Procedure Number Procedure Title Section 1 Dissolution of Plutonium Metal with Hydrochloric Acid at Room Temperature 9 2 Dissolution of Plutonium Metal with Hydrochloric Acid and Heating 10 3 Dissolution of Plutonium Metal with Sulfuric Acid 11 4 Dissolution of Plutonium Oxide and Uranium-Plutonium Mixed Oxide by the Sealed-Reflux Technique 12 5 Dissolution of Plutonium Oxide and Uranium-Plutonium Mixed Oxides by Sodium Bisulfate Fusion 13 6 Dissolution of Uranium-Plutonium Mixed Oxides and Low-Fired Plutonium Oxide in Beakers 14 7 Open-Vessel (with Reflux Condenser) Dissolution of Plutonium Oxide Powder 15 8 Open-Vessel (with Reflux Condenser) Dissolution of Mixed Oxide Powder 16 9 Closed-Vessel Hot Block Dissolution of Plutonium Oxide Powder 17 10 Open-Vessel (with Reflux Condenser) Dissolution of Mixed Oxide Pellets 18 1.5 The values stated in SI units are to be regarded as standard. The non-SI unit of molarity (M) is also to be regarded as standard. Values in parentheses (non-SI units), where provided, are for information only and are not considered standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

27.120.30