ORNL-1816 - the Molten Salt Energy Technologies Web Site

It should be noted that of the types of reactions
discussed above only a few examples have been
studied experimentally in a detailed or quantitative
way; most have not been studied at all or else
are represented experimentally by some of the
more obvious and less interesting examples.
kali Metal Solutions at
High Temperatures
G. P. Smith M. E. Steidlitz
rgy Division
In the prece port12 data were given for
the flammability of alloys of the sodium-bismuth
system. Additional data have now been obtained
for bismuth-rich alloys that provide a much more
complete picture of the reactivity of this system.
The relative reactivity of sodium-bismuth solutions
with dry air at 700°C as a function of the mole
fraction of sodium is shown in Fig. 6.17. The
relative reactivity scale is arbitrary. Pure sodium
was assigned a reactivity of four units. Unreactive
solutions were assigned a reactivity of
zero. No measurements were made for mole
fractions of sodium between 0.6 and 1.0 because
a solid compound of composition Na,Bi precipitates
from solution at a male fraction of sodium
somewhat greater than 0.6.
A temperature-composition diagram for liquid
sodium-bismuth solutions is presented in Fig.
6.18, on which is plotted a curve that approxi-
12M. E. Steidlitz, L. L. Hall, and G. P. Smith ANP
Quar. Prog. Rep. Sept. 10, 1954, ORNL-1771, p 105.
5
I
PERIOD ENDlNG DECEMBER 70,1954
mately separates the region of reaction from the
region of no reaction. The circles and triangles
on this diagram represent the temperature-compo-
sition values at which tests were conducted.
Most of the circles represent two to folur tests
each. The open circles represent tests in which
reaction occurred, while the black circles repre-
sent those which showed no reaction. The black
triangles represent conditions under whiich part
of the tests showed no reaction, while the rest
of the tests showed a slight reaction. ‘The two
open triangles represent tests which showed an
exceedingly slight amount of reaction. The broken
portion of the curve is poorly defined, inasmuch
as it may actually pass beneath the open triangles
rather than above them, as shown. It may be noted
that jets of pure bismuth showed appreciuble re-
activity at 800°C but not at 75OOC.
When air was saturated with water vapor, the
line of zero reactivity was shifted toward lower
sodium concentrations by a smal I but appreciable
amount for sodium-bismuth solutions. This effect
is shown for sodium-bismuth solutions at 700°C
in Fig. 6.19. It may be seen that, although data
for moist air scatter badly, there is unquestionably
a small shift toward lower sodium concentrations.
Combustion studies have been run on four of the
six alkali metal-alkali halide systems far which
, , , I ORNL-LR-rWG
9oo
800
700
600
UNCLASSIFIED
4654,
500 I
0 0.2 0.4 0.6
MOLE FRACTION OF SODIUM
Bismuth Solutions with Cry Air at 700°C as a Bismuth Solutions Did and Did Not React with
Function of the Mole Fraction of Sodium. Dry Air.
97