CHEMICAL ENGINEERING DIVISION SUMMARY REPORT FOR APRIL, MAY, JUNE 1959

Chemical-Metallurgical Processing. A direct-cycle Pyrometallurgical fuel-reprocessing plant is being designed in conjunction with the EBR-II reactor. Studies were continued on processing of melt-refining residues (crucible skull material). Skull oxlde reductions in Mg--Cd solutions are in progress. Methods of isolation of Pu from EBR-II bIanket material are being examined. Cadmium contafntng ~2% U and 0.2% Mg is betng circulated at 550 deg C by an electromagnetic pump. Solubilities of Ru, Ce, and La in Cd were measured at temperatures from 325 to 625 deg C; the solubility of U fn Zn was measured at temperatures from 425 to 800 deg . The high-Cd covers of the termary systems Cd-- U--Zn amd Cd--U-- Mg were investigated. Sixteen colorimetric combustions in oxygen were completed with natural MoS/sub 2/. Eight successful colorimetric combustions of Mo in F/sub 2/ were completed. Fuel Cycle Application of Volatility and Fluidization Techniques. Studies on the rates of fluorination of UO/sub 2/, as ft would appear in irradiated fuels, are in progress. Equilibrium constants are being obtained at various temperatures for the dissociation reaction of PuF/sub 6/ to F/sub 2/ and PuF/sub 4/. A systematic study of the reaction of Ni with F/sub 2/ is in progress as a part of the study of metal reactions with fluorine. A fluid-bed volatility process for the recovery of U from Iow-U-- Zircaloy-2 fuel alloys is under development. A graphite dissolver- hydrofluorinator was gfven a shake-down test wfth a dummy fuel element. Feasibility studies on the calcination of simulated Purex process wastes were successful in providing a freeflowing, granular solid with a volume reduction factor of 4.7. Preliminary tests of a one-step, continuous fluid-bed process for the conversion of UF/sub 6/ to UO/sub 2/ were made in a l 1/2-in-diam. Monel column. Reactor Safety. The pyrophoric nature of-the reactor metals U, Zr, Th, and Pu are being investigated. The experimental program to determine rates of reaction of molten reactor fuel and cladding metals with water is continuing. A series of runs with U was completed. Reactor Chemistry. The decay characteristics of K/sup 42/ and Te/sup 132/ are being studied. Work has begun on a study of the reactions of superheated steam with metals, such as Zr, Zircaloys, and stainless steel. (For preceding period see ANL-5996.) (W.L.H.