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ANP PROJECT PROGRESS REPORT
REDUCTION OF UF, BY STRUCTURAL METALS
J. D. Redman
Further studies were made, by use of the filtration
method, of the reduction of UF b chromium and
4.
by iron in reaction mediums that differed from those
used previously. In the earlier studies, the reaction
mediums used were NaF-ZrF, (50-50mole%,’
x3-47 mole %, 59-41 mole %5), NaF-LiF-ZrF,
(22-55-23 mole %),6 and NaF-LiF-KF (11.5.46.5-42
mole %).’ Other alkali fluoride mixtures containing
ZrF, have been employed as reaction mediums in
the recent studies in order to determine the effects
of various alkali fluorides on the interaction of
UF, with chromium or iron. The results obtained
by using KF-ZrF, or LiF-ZrF, (both 52-48 mole 75)
as reaction mediums are presented in Tables 2.2.1
and 2.2.2.
’J. D. Redman and C F. Weaver, ANP Quat. Pmg.
Rep. June 10, 1954, ORNL-1729, p 50; ANP Qmr-
Prog. Rep. Sepf. 10, 19S4. ORNL-1771, P 60.
4J. V. Redman and C. F. Weaver, ANP Qua?. frog.
Rep. ]me 10, 1955, ORNL-1896, p 60.
5J. D. Redman, ANP Quar. Prog. Rep. March 10, 1956,
ORNL-2061, p 93.
6J. D. Redman and C F. Weaver, ANP Qtrar. bog.
Rep. Sept. 10, 1955, ORNL-1947, p 74.
7J. D. Redman and C F. Weaver, ANP Qwr. Prog.
Rep. March IO, 195s. ORNL-1864, p 56.
TABLE 2.2.1. DATA FOR THE REACTION OF UF,
WITH CHROMIUM IN MOLTEN KF-ZrF, (52-48 MOLE %)
AT 600 AND 800°C
94
Conditions of
Equilibration
Present in Filtrate
Temperature Time Total U Total G* Total Ni
(O C) (hr) (wt %I (PP~) (PPm)
600 3 8.0 1030 35
3 9.4 1060 55
5 9.7 1180 55
5 8.5 1060 235
800 3 8.2 1250 35
3 8.4 1190 25
5 8.1 1150 295
5 8.1 1150 285
16 8.2 1060 30
16 8.2 1140 5
*Blank of 290 ppm of Cr at iO@C
Data for the reaction of UF, with chromium at
600 and 800OC in the reaction medium KF-ZrF4
(52-48 mole %) are given in Table 2.2.1. In these
runs approximately 2 g of chromium was reacted
with UF, (10.6 wt %, 4.0 mole %) dissolved in
approximately 40 g of the KF-ZrF, mixture con-
tained in nickel. Similar studies were made with
LiF-ZrF, (52-48 mole %) as the reaction medium at
a UF, concentration of 12.0 wt % (3.9 mole %). In
these studies chromium from two different sources
was employed; the results are given in Table 2.2.2.
As seen from the data in Table 2.2.2 the equi-
librium chromium concentrations are the same at
both temperatures for the two different chromium
metals used - hydrogen-fired electrolytic chromium
TABLE 2.22. DATA FOR THE REACTION OF UF4
WITH CHROMIUM IN MOLTEN LIF-ZrF, (52-48 MOLE %)
AT 600 AND 80O0C
Conditions of
Equilibration
Present in Filtrate
Temperature Time Total U Total G* Total Ni
(OC) (hr) (wt %I (ppm) ( P P ~
600 3
3
5
5
5
5
12
12
800 3
3
5
5
5
5
12
12
9.9 2550 30
9.8 3000 75
10.0 2980 70
9.4 3060 45
9.5 2800** 50
9.5 2790** 50
9.6 2910 30
9.6 3060 35
10.1 3820 5s
9.2 3830 30
8.9 4070 35
8.6 4040 45
9.2 3810** 40
9.3 3780** 60
9.5 3780 60
9.5 3830 50
*Blank of 250 ppm of Cr at 800°C. Electrolytic chromium
hydrogen-fired at 1200°C was used In all runs except
those noted.
**Blank of 190 ppm of Cr at SOOOC. Very pure iodide
chromium, not hydrogen-fired, was used in these runs.
b,