Some observations of Pu(IV)-alkali double chlorides

Abstract

Mixtures of PuCl/sub 3/ and the alkali chlorides, in the mole ratio 1; 2, were melted and saturated with chlorine at 0.80 atm pressure and approximately 50 deg C above the melting point. No reaction of chlorine with the solution PuCl/ sub 3/ + 2LiCl was detected. Products of reaction of chlorine with solutions of PuCl/sub 3/ + 2NaCl and PuCl/sub 3/ + 2RbCl are optically isomorphous with Cs/sub 2/PuCl/sub 6/. Products of reaction of chlorine with the solution PuCl/sub 3/ + 2KCl are too fine grained to establish the isomorphism with certainty. The common reaction must be PuCl/sub 3/(l) + 2MCl(l) + 1/2Cl/sub 2/(g) = M/sub 2/uCl/ sub 6/ ( l); where M = Na, K, Rb, or Cs. Ranges of the non-stationary arrests indicate that the compounds containtng Na and K, and probably the Rb compound, are partly dissociated under the given conditions and that the stabilities of the M/sub 2/PuCl/sub 6/ compounds increase in the order Na, K, Rb, and Cs. Results are believed to confirm the opinion that appreciable quantities of Pu(IV) may be formed in binary solutions of most alkali chlorides with PuCl/sub 3/ when exposed to chlorine gas. (P.C.H.)