ORNL-1771 - Oak Ridge National Laboratory

The data obtained are presented in Table 5.8,
which gives the concentration of iron found in the
filtrate, the ratio of the HF concentrations in the
influent and effluent gases, and the equilibrium
constants and corresponding activity coefficients
for the FeF As is evident, the data in Table 5.8
2:
are less precise than those obtained by the dynamic
procedure. The lowered precision is probably due
to the more complex apparatus and technique. How-
ever, when the data are plotted (Fig. 5.8), the
spread of the data is less than the estimated un-
certainty in the AFO values. The agreement be-
tween the values obtained by the two methods is
remarkably good,
TABLE 5.8. EPUlLlBRlUM DATA FOR THE REACTION
FeF2 + H,+Fe' t 2HF AT 800°C IN MOLTEN
NoF-ZrF4 (53-47 mole %)
Concentration
of of FeF,
(ppm Fe)
912
223
915
7 40
360
185
160
27 5
Ratio of HF in
Influent Gas P2HF
to HF in
Effluent Gas
0.79
0.9 1
1.02
0.98
1.00
0.93
0.9 1
0.99
0.40
1.08
2.09
2.12
1.71
1.89
2.14
3.12
YFf2F2
0.4 1
0.74
1.43
1.45
1.17
1.30
1.47
2.14
PERlOD fNDING SEPTfhlBER 10, 1954
at 150 to 200°C. An attempt to prepare AgF by
reacting HF with AgCN was unsuccessful; most of
the AgCN did not react. Several botches of anhydrous
ZnF, were prepared by heating ZnF2.4H20
under HF at 600°C. The compound TeF4 was
prepared by reacting Te and HNO, and reacting the
resulting TeO, with aqueous H F to give Te02F2.H 20p
which was thermally decomposed to yield Te02,
HF, H20, and the product TeF,. The TeF, was
collected in a condenser held at 130 to 140°C.
Small quantities of Rb,CrF, and Li,RbCrF4 were
prepared by heating the proper quantities of CrF3,
RbF, and LiF in sealed capsules ai 900°C. The
Rb,CrF, has properties approximating those of a
corrosion product found in a rubidium-base fuel.
The compound RbCrF, was prepared by heating
CrF, and RbF at 800°C in a sealed capsule.
Numerous batches of structural metal fuel- or
coolant-type fluoride complexes were prepared.
Among these (prepared by methods previously
described) were: K,CrF,, K,Ni F, and KNi F,.
The compounds NiF,, FeF,, and FeF2 were prepared
in a high state of purity by hydrofluorination
of the corresponding chlorides.
FUNDAMENTAL CHEMISTRY OF FUSED SALTS
EMF Measurements
L. E. Topol
Mater i a1 s Cherni s try Di vi s ion
-
Av 1.84 1.25
Additional measurements of decomposition potentials
of KCI and of various chlorides in molten
KCI at 850T were mude. Morganite (AI 0 )
? 3
crucibles were employed with all the melts studied.
Preparation of Various Fluorides
Platinum and nickel were used as cathodes, and
B. J. Sturm E. E. Ketchen
the anodes were of nickel, carbon (graphite),
Materials Chemistry Division
chromium, and zirconium.
The solutions of various chlorides in KCI were
The simple structural metal fluorides have conprepared
by melting 2 moles of KCI with 1 mole of
tinued to be used extensively for numerous purthe
anhydrous chloride in a sealed, evacuated
poses. A limited interest also has been maintained
quartz tube. More dilute solutions were prepared by
in several of the complex fluorides formed by the
adding appropriate quantities of KCI to the 33.3%
interaction of alkali fluorides with structural metal
KCI mixtures so obtained. The data obtained
fluorides. Some effort also has been expended on
recently are given in Table 5.9.
the preparation of other simple fluorides, as well as
The value of 1.5 v found upon electrolysis of KCI
on the purification of small quantities of the strucwith
an anode of electrolytic chromium agrees with
tural metal fluorides. The identity and purity of
the value previously reported for chromium-plated
these fluorides have been established mainly by
gold wire in an atmosphere of helium,20 The more
chemical analysis supplemented by x-ray and petrorecent
value of 1.27 v for electrolytic chromium in
graphic data in some cases.
- _I___ - __
The with an ratio Of T. E. Topol, ANP Quar. Pmg. Rep. MUF. 10, 1954,
0.98, was prepared by heating Ag,CB, mder HF ORNL-1692, p 63.
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