skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: CHEMICAL ENGINEERING DIVISION SUMMARY REPORT, JANUARY, FEBRUARY, MARCH 1961

Abstract

8 7 < 6 ; : : = 8 g developed for recovering fissionable and fertile materials from shortcooled reactor fuels. The second laboratory demonstration of the melt-refining process with highly irradiated EBR- IItype fuel pins was completed. A 392-g charge of U-5% fissium fuel pins irradiated to an estimated burnup of 0.4 total at.% and cooled 28 days was melt refined for three hours at 1400 deg C. Data were not obtained on the behavior of fission products. The effect of N concentration on the nitridation rates of unirradiated U-fissium alloys in Ar-N atmospheres was determined. Experiments on the storage of fuel pins at 350 deg C in Ar atmospheres showed that the presence of 5% N lowered product yields only slightly during subsequent melt-refining operations. Supplementary pouring techniques, such as the use of probes and mashers designed to break crusts over the melts, are moderately effective, but are a less desirable solution to the problem of maintaining high yields than the elimination of contaminants in the Ar atmosphere. A liquid metal process is under development for recovery of the fissionable material contained in melt refining crucible skulls produced in the EBR-II fuel cycle. Information obtained in separate studiesmore » of the individual process steps is listed. A systematic study is underway to ascertain the influence of atomic size, metallic valence, and electronic configuration on the coprecipitation of various metallic elements with the Cd-Ce intermetallic phase CeCd/sub 11/. Values for the coprecipitation coefficient lambda , defined by the equation log (tracer in solution/ total tracer) = lambda log (carrier in solution/total carrier), were determined for Na, Li, K, Y, Ba, lambda = 0; La, lambda = 1.49; Th, lambda = 1.08; Pr, lambda = 0.63; Ga, lambda = 0.23; Sm, lambda = 0.17; U, lambda = 0.13; Sr, lambda = 0.10; Eu, lambda = 0.099; Sc, lambda = 0.05; and Zr, lambda = 0.04. In pilot-plant studies the reaction of 304 stainless steel tube sections with Cl was investigated in a 1 1/2-inchdiameter two-zone fluid-bed reactor. An average penetration rate of 4.6 mils/hr was obtained in a 4.7-hour run at 575 deg C using 87% Cl (in N). At 625 deg C, using the same Cl concentration, a 35-mil tube completely reacted in 3.8 hours. The effect of Cl dilution at 625 deg C was noticeable at concentrations below 48 vol.%. The rate of thermal decomposition of PuF/sub 6/ was studied at 140 to 173 deg C by a static method and from 150 to 250 deg C by a flow method. A study of the kinetics of decomposition established the mechanism of the reaction. The rate of the reaction has been formulated as concurrent first- and zero-order reactions with respect to PuF/sub 6/ pres sure in the range between 50 and 1100 mm at 140 to 170 deg C. The reaction of elemental Br with PuF/sub 6/ has been investigated. The stoichiometry of the reaction was established. Primary products of the reaction are PuF/sub 4/ and BrF/sub 5/. The utility of the reaction for the separation of U and PuF/sub 6/ was demonstrated. In studies of fission product behavior, mixtures of UO/sub 2/ - Ru/sup 106/ were reacted with F at 400 and 500 deg C. It was found that at both of these temperatures Ru was volatilized at a rate equal to or faster than that of U volatilization as UF/sub 6/. However, it was found that RuF/sub 5/ decomposed and was deposited on a colder portion of the walls of the fluorination vessel. Two series of in-pile, metal-water experiments were completed. Meltdowns were conducted on stainless steel-urania cermets, U wires, and on ceramic core, metal-clad fuel specimens. Cermets made of 90 wt.% stainless steel with urania showed similar behavior when submerged in water irrespective of whether the sample was in the form of pins or plates; metal temperatures greater than 1500 deg C were attained. The original geometry was changed into one or two large globules together with many fine particles; the more energetic transients also produced some fine (1-mil diameter) powder. Chemical analyses indicated that a separation of the urania from the stainless steel took place during the melting-quenching cycle of the reactor burst. The larger globules were depleted in U« less

Publication Date:
Research Org.:
Argonne National Lab., Ill.
OSTI Identifier:
4012788
Report Number(s):
ANL-6333
NSA Number:
NSA-15-025734
DOE Contract Number:  
W-31-109-ENG-38
Resource Type:
Technical Report
Resource Relation:
Other Information: Orig. Receipt Date: 31-DEC-61
Country of Publication:
United States
Language:
English
Subject:
GENERAL AND MISCELLANEOUS; ARGON; ATOMIC MODELS; BARIUM; BROMINE; BROMINE FLUORIDES; BURNUP; CADMIUM ALLOYS; CARRIERS; CERIUM ALLOYS; CERMETS; CHEMICAL REACTIONS; CHLORINE; CONFIGURATION; COOLING; DECOMPOSITION; DECONTAMINATION; DEFECTS; EBR-2; EFFICIENCY; ENERGY; EQUATIONS; EUROPIUM; FAILURES; FERTILE MATERIALS; FILMS; FISSION PRODUCTS; FISSIONABLE MATERIALS; FLUIDIZATION; FLUORINATION; FLUORINE; FUEL CANS; FUEL ELEMENTS; GALLIUM; GRAIN SIZE; HEAT TREATMENTS; HIGH TEMPERATURE; IMPURITIES; IN PILE LOOPS; INTERMETALLIC COMPOUNDS; LANTHANUM; LIQUID METALS; LITHIUM; MELTING; METALS; NITROGEN; PHASE DIAGRAMS; PLUTONIUM FLUORIDES; POTASSIUM; PRASEODYMIUM; PRECIPITATION; PRE

Citation Formats

. CHEMICAL ENGINEERING DIVISION SUMMARY REPORT, JANUARY, FEBRUARY, MARCH 1961. United States: N. p., 1961. Web. doi:10.2172/4012788.
. CHEMICAL ENGINEERING DIVISION SUMMARY REPORT, JANUARY, FEBRUARY, MARCH 1961. United States. https://doi.org/10.2172/4012788
. Tue . "CHEMICAL ENGINEERING DIVISION SUMMARY REPORT, JANUARY, FEBRUARY, MARCH 1961". United States. https://doi.org/10.2172/4012788. https://www.osti.gov/servlets/purl/4012788.
@article{osti_4012788,
title = {CHEMICAL ENGINEERING DIVISION SUMMARY REPORT, JANUARY, FEBRUARY, MARCH 1961},
author = {},
abstractNote = {8 7 < 6 ; : : = 8 g developed for recovering fissionable and fertile materials from shortcooled reactor fuels. The second laboratory demonstration of the melt-refining process with highly irradiated EBR- IItype fuel pins was completed. A 392-g charge of U-5% fissium fuel pins irradiated to an estimated burnup of 0.4 total at.% and cooled 28 days was melt refined for three hours at 1400 deg C. Data were not obtained on the behavior of fission products. The effect of N concentration on the nitridation rates of unirradiated U-fissium alloys in Ar-N atmospheres was determined. Experiments on the storage of fuel pins at 350 deg C in Ar atmospheres showed that the presence of 5% N lowered product yields only slightly during subsequent melt-refining operations. Supplementary pouring techniques, such as the use of probes and mashers designed to break crusts over the melts, are moderately effective, but are a less desirable solution to the problem of maintaining high yields than the elimination of contaminants in the Ar atmosphere. A liquid metal process is under development for recovery of the fissionable material contained in melt refining crucible skulls produced in the EBR-II fuel cycle. Information obtained in separate studies of the individual process steps is listed. A systematic study is underway to ascertain the influence of atomic size, metallic valence, and electronic configuration on the coprecipitation of various metallic elements with the Cd-Ce intermetallic phase CeCd/sub 11/. Values for the coprecipitation coefficient lambda , defined by the equation log (tracer in solution/ total tracer) = lambda log (carrier in solution/total carrier), were determined for Na, Li, K, Y, Ba, lambda = 0; La, lambda = 1.49; Th, lambda = 1.08; Pr, lambda = 0.63; Ga, lambda = 0.23; Sm, lambda = 0.17; U, lambda = 0.13; Sr, lambda = 0.10; Eu, lambda = 0.099; Sc, lambda = 0.05; and Zr, lambda = 0.04. In pilot-plant studies the reaction of 304 stainless steel tube sections with Cl was investigated in a 1 1/2-inchdiameter two-zone fluid-bed reactor. An average penetration rate of 4.6 mils/hr was obtained in a 4.7-hour run at 575 deg C using 87% Cl (in N). At 625 deg C, using the same Cl concentration, a 35-mil tube completely reacted in 3.8 hours. The effect of Cl dilution at 625 deg C was noticeable at concentrations below 48 vol.%. The rate of thermal decomposition of PuF/sub 6/ was studied at 140 to 173 deg C by a static method and from 150 to 250 deg C by a flow method. A study of the kinetics of decomposition established the mechanism of the reaction. The rate of the reaction has been formulated as concurrent first- and zero-order reactions with respect to PuF/sub 6/ pres sure in the range between 50 and 1100 mm at 140 to 170 deg C. The reaction of elemental Br with PuF/sub 6/ has been investigated. The stoichiometry of the reaction was established. Primary products of the reaction are PuF/sub 4/ and BrF/sub 5/. The utility of the reaction for the separation of U and PuF/sub 6/ was demonstrated. In studies of fission product behavior, mixtures of UO/sub 2/ - Ru/sup 106/ were reacted with F at 400 and 500 deg C. It was found that at both of these temperatures Ru was volatilized at a rate equal to or faster than that of U volatilization as UF/sub 6/. However, it was found that RuF/sub 5/ decomposed and was deposited on a colder portion of the walls of the fluorination vessel. Two series of in-pile, metal-water experiments were completed. Meltdowns were conducted on stainless steel-urania cermets, U wires, and on ceramic core, metal-clad fuel specimens. Cermets made of 90 wt.% stainless steel with urania showed similar behavior when submerged in water irrespective of whether the sample was in the form of pins or plates; metal temperatures greater than 1500 deg C were attained. The original geometry was changed into one or two large globules together with many fine particles; the more energetic transients also produced some fine (1-mil diameter) powder. Chemical analyses indicated that a separation of the urania from the stainless steel took place during the melting-quenching cycle of the reactor burst. The larger globules were depleted in U},
doi = {10.2172/4012788},
url = {https://www.osti.gov/biblio/4012788}, journal = {},
number = ,
volume = ,
place = {United States},
year = {1961},
month = {10}
}