METHOD OF DISSOLVING PLUTONIUM DIOXIDE, MOX-FUEL SCRAP AND EXTRACTING AMERICIUM

摘要

FIELD: nuclear equipment.;SUBSTANCE: invention relates to nuclear engineering, particularly to processes of dissolving plutonium dioxide (PD) during refining thereof for use in producing uranium-plutonium fuel (particularly MOX fuel), dissolving scrap of MOX-fuel (powders and tablets of uranium-plutonium fuel) and separation of americium at their carrying out. When dissolving plutonium dioxide and scrap MOX-fuel cerium is used as an oxidising agent, and for its regeneration in addition to electrochemical method ozone is used. When dissolving scrap MOX-fuel, first dissolving uranium in scrap at temperature 50–80 °C with simultaneous supply of ozone under the solution mirror and with cerium concentration of up to 0.05 M/l, and then at temperature of 30–50 °C is dissolving plutonium also with ozone feed or together with electrochemical oxidant generation. In oxalate deposition, the cerium which is present in the raffinate is used as a coprecipitate of americium. At insufficient concentration of americium in a mixture of americium and cerium oxides mixture is returned to operation of dissolution of PD, and at sufficient concentration of americium – for temporary storage.;EFFECT: invention enables to use cerium as an oxidising agent and coprecipitating americium when dissolving PD and oxalate deposition, respectively.;1 cl