ORNL-1771 - Oak Ridge National Laboratory

ANP QUARTERLY PROGRESS REPORT
~~ -
TABLE 5.5. EBUlLlBRlUM DATA FOR THE REACTION FeO + 2 U F 4 4 2UF3 + FeF2 IN MOLTEN NaZrF5
.-
Experimental Conditions .-...... I_
Concentration
of
Temperature UF, Added UF3 Added FeF2 Added Fe" in Filtrate K,
(OC) (moles/kg of melt) (rnoledkg of melt) (moles/kg of melt) (PPld
~
600 0.322
0.322
0.326
0.326
0.053 0.03 19
0.053
0.083
0.083
0.0346
0,0347
0.0347
6 20 1.2 x 10-6
735 1.2 x 10-6
660 9.3 x 10-6
6 55 9.3 x 10-6
0.321 0.036 0.0 168 995 2.1 10-~
0,321 0.036 0.0168 9 40 1.9 10-~
800 0.242
0.113
0.206
8600 1.2 x 10-5
0.242
0.1 13
0.103
3210 3.2 10-~
0.242
0.1 13
0.103
3270 3.7
0.277
0.077
0.103
41 10 2.7
0.277
0.077
0.103
4050 2,2 10-~
0.0318 0.322 0.213 3110 3*4 x 10-6
0.0318
0.322 0.210
3300 2.5 10-~
0.103
0.27 1 0.210
4530 1.1 10"~
0.103
0.271 0.207
4645 3.7 10-5
0.207
0.152 0.213
7940 1.3 10-5
0.245 0.1 15 0.053 495 4.2 x
0.245 0.1 15 0.053 435 2.8 x 10-6
_..___.
0.245
__ ..........
0.1 15 0.053
........ ~ _ _ _ _ ..... _
265
. ~
1.3 10-~
....... ____
*Values previously reported: ot 6OO0C, Ku = 1.2 x at 8OO0C, Kr 7 1.5 x lo-'.
K calculated from --/\F0 = RT In K by using Brewer's values for AF0:
' q eq
at 6OO0C, Keq= 2x at 8OO0C, Keq= 1.4~
6QOOC (1 x lom5) agrees with the previously re-
ported value of 1.5 x loa5, although agreement
among the individual determinations was not en-
couraging. The values obtained at 80O0C, however,
$0 not agree well with the value of 1.5 x
reported when UF, and ferrous metal were used as
starting materials.
In an attempt to explain this discrepancy, the
experiments in which UF, and ferrous metal were
used os reactants at 80OOC were repeated. The
values obtained, as shown in Table 5,6, yielded a
mean of 0.9 x and agreed more closely with
the previously reported values. It appears possible
that the reaction of ferrous metal with UF, had
not reochedequilibrium in the reaction time allowed.
62
lo-,.
TABLE 5.6. EQUlLlBRlUM DATA FOR THE
REACTlON OF FERROUS METAL WlTH
UF4 IN MOLTEN NaZrF5 AT 800°C
UF4 added: 0.360 niolekg of melt
.. . -... ~ ___
Concentration*
of ~e++ in Filtrate Kx
(PPm)
520
390
330
480
1.7 x
5.4 x 10-7
2.8 x lo-'
1.1 x 10-6
*Blank of 100 ppm to be subtracted from determined
values in calculations.