LIQUID-LIQUID EXTRACTION OF MOLTEN URANIUM WITH SILVER

In recent years inte~ea·c in the United States in the nuclear field has been turning towards power reactors. Among the many problems that must be solved before eco~'loraical electrical power can be produced from nuclear reactors are the p~oblems connected with the processing of spent reactor fuels. T~1e only reactor fuel processing methode available at preaent, the aqueous processes, are relatively complex, destroy the metallic cha.ractel" of the fuel, require "long-cooled" fuels necessitating h i gh inventories of fissionable m.ate:"'ial, and J.eave huge volumes of :•ad~oac ti ve waste solutions to be pr·ocessed and sto:"'ed. For these reasons lnterest has been turn:.ng to":rerds othe:i."" processing methods, including 11 pyropJ..~ocess:!.:ng 11 b~yr l:tquid-J.iq_uid ext rae tion of the mol ten fuel with sil ve:;."'. ':L'he purpose of this study was to develop a part of the equipmen'.; e.nd tec!::mology needed to a tudy the ext; rae t:i.on of uranium wi th ail ver• and to asce:"'ta.in some of the . prQbler.lS that m~cght be expected in p:.::>ocessing of spent reactor fuels with a ail ver extraction .. A vacuum system wo.s bui1 t in ~rhich to ca:;-ry out uraniumsilver contacting; induction heating equipment was 3et up to heat the materials. Tempel"'a.tu:;."'e measuring 1ne'chods and techniques for use in liquid metal extrac 'cion WO:i."l{ alBo were studied. Chromel-alumeJ., platinum-platinum !'llodium, and columbj.um-tungsten thermocouples were investigated. G::>a.phi te was selected as the best eontainer material for the molten metals and was used satisfactorily in all of this work . . I A number o.f ~u.r2.nium-sil ver melts wer~ nw.c.le in wh:tc:1 the phase separation and mass trans:fer were studi ed. Phase. sepa:;."ation was sharp but occasional ~roscopic inclusions were found in both phases. Microscopic phase ·separatior. was complete. Uranium