ORNL-1816 - the Molten Salt Energy Technologies Web Site

P
as its chief impurity about 0.2 wt % sulfur. Purification
of the RbF has proved to be difficult due to
attack of the nickel purification equipment by the
sulfur. It has been found possible by rigorous HF
5
f and H, treatments to reduce the sulfur content to
0
- t
.- %.
an acceptable value, but in the process a large
amount of nickel is picked up by the melt. Con-
siderable treatment time is required to reduce the
resulting nickel fluoride so that it may be removed
from the product.
Preparation of Various Fluorides
B. J. Sturm E. E. Ketchen
structural metal fluorides and several complex
from these and alkali
ed. These materials a
fluorinated UF, are being utilized at increasing
rates for various investigations of interest to the
ANP program. Chemical analysis, supplemented
by x-ray and petrographic examination, has been
utilized to determine purity and identity of the
materials.
Uranium tetrafluoride, as received, may contain
small amounts of oxides, moisture, and higher-
ce uranium, Hydrofluorination at 6OOOC is
carried out as a satisfactory method of re-
P moving these impurities. During the quarter, 11 kg
of the purified material was supplied for studies
requiring high-purity UF,. Additional batches of
NiF, were prepared by the hydrofluorination at
6OOOC of partially dehydrated NiCl ,*6H,O. Anhydrous
AIF, was prepared by the thermal de-
c
,.
PERIOD ENDING DECEMBER 70,1954
Fluorination of NiF,, CrF,, and FeF, has been
discontinued because the analytical [methods
available are not able to establish the fluorine-to-
metal ratios accurately enough to determine the
effectiveness of the BrF, treatment in r'emoving
small amounts of oxides that may be present.
CHEMISTRY OF ALKALI HYDROXIDES
L. G. Overholser F. Kertesz
Materials Chemistry Division
Purification of Hydroxides
E. E. Ketchen
Materials Chemistry Division
Approximately 5 kg of NaOH was purified either
by filtering a 50 wt % aqueous solution through a
fine sintered-glass filter or by decantinci a 50%
solution to remove insoluble Na,CO,. 111 either
case the material was then dehydrated at 400OC.
Both methods produced material of desired purity
(-0.1 wt % each of H,O and Na2C03). About
1.8 kg of high-purity KOH (-0.1 wt % each K,CO,
H,O, and Na) was prepared by reacting pure po-
tassium with water, It is not planned to prepare
more hydroxides in the near future because the
material on hand should supply the present limited
requirements.
Effect of Additives on Hydrogen Pressure
Over NaOH-Ni System
F. A. Knox
Materia I s Chemistry Di vis ion
The effects of small additions of NiO, Na,O,
and mixtures of the two on the hydrogen pressure
by using a modification rev i ou s I y desc r i bed
the formation of
Three batches of FeF, were fluorinated as a
,,ANP Quar. Prog. Rep. Sept. 10, 1953, ORNL-1609,
means of removing small amounts of impurities. p 84.
71