ORNL-TM-2316.txt

 

RECEIVED BY m'"“ A1n 971988 =

 

_OAK RIDGE NATIONAI. I.ABORA'I'ORY
| , operated by - L
UNION CARBIDE CORPORATION - '
: for ihe- Loy -
U S. ATOMIC ENERGY COMMISSION

ORNI. TM 2316

   

 

PHXSICAL PROPERTIES OF MOLTEN~-SALT REACTOR FU'EL,
- COOLANT, AND FLUSH SALTS

© Eaited by S. Cantor

 

o - Contributors:

L . 8, Cantor ,
e - J. W. Cocke =
: :“: A. S. Dworkin -

G, M. Watson |

 

 

1
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ORNL-TM~ 2316
Contract No. W-7405-eng-26
REACTOR CHEMISTRY DIVISION

PHYSICAL PROPERTIES OF MOLTEN-SALT REACTOR FUEL
COOLANT, AND FLUSH SALTS ’

Edited by S. Cantor

Contributors:

. Cantor

. W. Cooke

. 5. Dworkin
. Robbins
. Thoms

. Watson

W eYm

=

AUGUST 1968

CAK RIDGE NATIONAL LABCRATORY
Oak Ridge, Tennessee
opergted by
UNION CARBIDE CORPORATION
for the
U.S5. ATOMIC ENERGY COMMISSION

LEG AL NOTICE

red work. Neither the United

 

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Ag uged in the sbove, ‘‘person acting on behalf of the Commigsion” includes any em= ; Mfi«::}{ C}F Thir
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iii

a4 CONTENTS

Page
ADEETECE o v v i e e e e e e e e e e e e e e e s e e e e e e e e e 1
Compesition of Salt Mixtures 2
Introduction 3
Basis for Selectlng the Salts 3
Uncertainties Listed with the Phy81cal Propertles Values 6
For Further Informgtion 7
Viscosity . . 8
Thermal Conductiviiy .« ¢ ¢« ¢ o ¢ ¢ ¢ ¢ ¢ o o« o o o« o o ¢ o o ¢ « + o 11
Electrical Conductivity . . ¢ ¢ v ¢ ¢« o o o o o 4 o « o o o + ¢ o« + « 14
Phase Transition Behavior . . . P I -
Phase Diagram of LiF- Bng—ThF4 e e e e e s e e e e e e e e e e . 20
Phgse Disgram of NaBF,-NaF e e e e e e e e e e e e e e e e e e 21
Heat Capacity (at constant pressure) . . . + « « « o v o ¢ v o« o « + 22
Heat of FUSION . « v ¢ v v v ¢ 4 & ¢ o s o & o o o o « o« v s e o o« 25
Density of Liguid e e e e e e e e e e e e e e e e e e e e e e e . 28
Expansivity (Volume Coefficient of Thermal Expansion) . . . . . . . . 30
Compressibility P
Vapor Pressure e e e e e e e s e e e e e e e 4 e e e e e e e e . 33
Surface Tension Gt e e e e e e s e e e s e e e e e e e s e s e s . . 36
Solubility of Helium, Krypton, and Xenon . . . . . « « « « + « « « & 38
Solubility of BF3 Ga88 . ¢ o ¢ & o o« 4 « « o o ¢« 4 4 ¢ 4 o s 0 o o . 4l

Appendix

A. Isochoric Heat Capacity (C,), C /Cv, and Sonic Veloecity . . . 43
B. Thermal Diffusivity, Klnematlc V1800$1ty, and Prandtl Number . 41
C. Conversion FactOTs « + « o ¢ « « o o « o o« o o o o o ¢ o o « o« 45

Composition of Salt Mixtures . . . . + « « v ¢ « ¢ ¢ ¢« « ¢ v « ¢« « . 46
 

 
From the foregoing properties,
calculated and appended:

ABSTRACT

For seven molten salt mixtures:

four fuel mixtures, each containing LiF, BeF,, ThF,, UF,
one flush salt, LiF-BeF, (66-34 mole %)
two coolant salts, NaBF,-NaF (92-8 mole %) and single-

component NaBF,

estimates and/or experimental values are given for the follow-
ing properties:

viscosity,

thermal conductivity,
electrical conductivity,
phase transition behavior,
heat capacity,

heat of fusion,

density,

expansivity,
compressibility,

vapor pressure,

surface tension,

solubility of the gases, He,Kr,Xe,BF, .

isochoric heat capacity (CV)
sonic velocity

thermal diffusivity
kinematic viscosity

Prandtl number.

the following have also been
Composition of Salt Mixtures

Symbol

F
Fuel- F,
Breeder
Mixtures ¥

Fy
Flush Salt L,B
(present MSRE
coolant)
Coolants C,

C;

 

 

 

 

Mole % Liquidus
LiF BeF, ThF, UF, Temp. (°C)
73 16 10.7 0.3 500° + 5©
72 21 6.7 0.3 500° + 5°©
68 20 11.7 0.3 480° + 50
63 25 11.7 0.3 500° + 50
66 34 - - 458° + 1°
(peritectic)
NaBF, NaF
g2 8 3850 + 1©
' {(eutectic)
100 - — 407° + 1°
(melting
point)
'3
_________ INTRODUCTION

In this document we have compiled physical property infor-
mation, either measured or estimated, on seven salt mixtures
that are presently of importance in the design of advanced
molten salt reactors. The primary user of this compilation
will, no doubt, be the nuclear reactor engineer who requires
these data for the design and development of molten salt re-
actors. Specialists in the chemistry of molten salts may be
another audience interested in this report. We earnestly hope
that all who critically examine or otherwise use these data
will give us the benefit of their advice so that future ver -
sions of-'this document can be greatly improved.

Basis for Selecting the Salts

 

The choice of salt mixtures has been primarily governed
by recent changes in the Molten Salt Reactor Program: (a)
the combining of fissile and fertile material within the same
circuit (the "single-region" concept), and (b) the testing of
coolant salts which are mainly NaBF,.

Four mixtures have been selected for possible use as
single-region fuel melts. These are:

Composition (mole %)

 

 

Salt Mixture LiF BeF, ThF, UF,
F, 73 16 10.7 0.3
F, 72 21 6.7 0.3
F, 68 20 11.7 0.3
F, 63 25 11.7 0.3
4

Salts F;, and F; are fuel mixtures appropriate toa .
prismatic configuration of the graphite moderator; the lesser
concentrations of BeF, and ThF; in F; may be more favorable
with respect to rare-earth fission product removal by reduc--
tive extraction.

Salt F,, containing a relatively low concentration of
thorium, might be used in a reactor (e.g., with random-packed
graphite spheres) where good breeding performance is not a
prime consideration. Mixture F,, on the other hand, could
contribute to improved breeder performance mainly because
the higher the beryllium concentration, the greater the
opportunity to increase neutrons by the (n, 2n) reaction.

It is worthwhile noting that for the purposes of
estimating physical properties of salts F,-F,, the effects
of the small concentration of UF, was almost always assumed
to be the same as for the corresponding increase in the ThF,
concentration.

Although no firm decision has been reached as to the
exact composition of the fuel salt for the next molten salt
reactor, it is highly probable that the concentrations of
LiF, BeF, and ThF, will be within the limits given for these
components by the above four mixtures.

Physical property information is also provided for:

LiF-BeF, (66-34 mole %) symbolized as L;B.
This mixture has been used in the MSRE as the coolant and as

the flush salt for the fuel circuit. The inclusion of L;B
e

5
in this report is justified by the good possibility that it
will be a flush salt (and perhaps a coolant) in future molten
salt reactors.

As intermediate coclant (in this case the fluid which
transports heat from the fuel salt to the steam generators)
the salts which presently appear attractive contain mostly
NaBF,. Two such salts are considered:

Composition (mole %)

Coolant NaBFg NaF
C, 100

The salt symbolized as C; is a eutectic composition
which melts at 385°C (725°F). Although a lower melting
fluoroborate mixture would be desirable, it is not presently
clear how much and which additive will substantially depress
the melting temperature. Moreover, it seems likely that
lower melting fluoroborate mixtures will not be very differ-
ent from C, ; hence mixture Cg seems, at present, the leading
candidate for the next coolant to be tried in a molten salt

reactor.

Another salt for which estimates are tabulated in this
report is '"'pure' NaBF,, symbolized as C,. Since stoichio-
metric NaBF, does not exist in the molten state without a
very high partial pressure of BF; gas, C, cannot be considered
a practical coolant. However, estimations of the physical
properties of hypothetically pure molten NaBF; are useful

for evaluating the contributions of NaBF, as a component in
a salt mixture. In solution, [BF,] ion may be imagined to s
behave like a halide ion, slightly larger and more polarizable
than iodide ion. By applying this analogy, several properties
of C, were estimated from the measured properties of molten
Nail.

For convenience, a list of salt compositions and their
corresponding liquidus temperatures are given after the

abstract (page 2) and at the end of this report (page 46).

Uncertainties Listed with the Physical Property Values

Each contributor has stated what he believes is the
error associated with the experimental result or with the
estimated quantity. For most cases, the uncertainty repre-
sents considerably more than either '"goodness of fit'" of an
interpolation or internal consistency available from thermo-
dynamics. Instead, the uncertainty may be considered as the
largest probable combination of systematic and random errors
associated with the value given for the property. Where the
listing is a property-temperature equation, the uncertainty
is for the property calculated  at the temperature substituted
in the equation. In properties where the number of signifi-
cant figures are not justified by the specified uncertainties,
the extra significant figures are given to aid the reader in
judging whether a particular salt is '"less than" or ''greater
than' another salt for the property in question.

Although the magnitudes of the uncertainties are highly

intuitive and often disappointingly large, they should be
.......

L taken seriously. Each contributor, while not necessarily
qualifying as "expert' in the physical property, either
possesses long experience in measuring the property or has
carefully (and usually critically) reviewed the literature
for that property. In other words, for each property the
person whose name is given is at least a very interested

observer and may also be an active participant,

For Further Information ---

It is best to contact the person (or persons) listed
under the property heading. The editor hopes to provide
addenda to this report as newer, more reliable, data become

available.

R
VISCOSITY | i’

S. Cantor

Viscosity-Temperature Equation

 

 

Salt n in Centipoise, T in °K Uncertainty
F; n = 0.084 exp (4340/T) 25%

F, nmn = 0.072 exp (4370/T) 25%

F, n = 0.077 exp (4430/T) 25%

Fyu \ n = 0.0444 exp (5030/T) 25%
L,B n = 0.116 exp (3755/T) 15%

C

C, n = 0.04 exp (3000/T) 50%

Sources of Data and Methods of Estimation
Salts ¥, -F,: Estimated empirically from viscosities in the
system LiF-BeF,-UF, (ref. 1) and also from measurements of
LiF-BeF, -ThF, (71-16-13 mole %).° It was assumed that the
effect of ThF, concentration on viscosity was the same as
that observed for UF,.
L,B: Measured3
C; and C,: The equation was derived from (a) preliminary
measurements of NaBF4,4 and (b) assuming that the temperature
variation of viscosity for NaBF, is equal to that of NaI.5

Given the rather large uncertainty, the contribution of NaF

(in C;) to the viscosity may be considered negligible.
9
Discussion

Viscosities of Reactor Fuel Mixtures

 

From the reported viscosity measurementsl of the system
LiF-BeF, -UF,, two trends can be observed:

(a) for LiF concentrations of 60 mole % or greater, substitu-
tion of UF, for BeF, (at const. temp.) causes an increase in
viscosity,

(b) increasing LiF from 60 to 70 mole %, at const. temp. and
at const. UF, concentration, decreases the viscosity by, at
most, a factor of 1/2; for most compositions the factor is
closer to 3/4.

The data and trends observed for the system LiF-BeF, -UF,
can servé to predict reliably (i.e., to within 25%) the
viscosities in the slightly different system, LiF-BeF,-MF,

(M is Th and/or U). Assuming that all single-region fuel
mixtures will be restricted to the following ranges of component
composition:

62 - 73 mole % LiF

15 - 30 mole % BeF,

6 - 16 mole % MF, ,
then one may conclude that the predicted viscosities have a

rather narrow range of values, e.g.,

 

at 60000, 9 - 16 Centipoise

at 700°C, 5 - 9 Centipoise
10

References

1. B. C. Blanke et al., "Density and Viscosity of Fused
Mixtures of Lithium, Beryllium, and Uranium Fluorides,"
MLM-].OSé, DeCo 19560

2. Molten Salt Reactor Program Quar. Progr. Rept. Oct. 31,
1959, ORNL-2890, p. 21.

 

3. 8. Cantor and W, T. Ward, Oak Ridge National Laboratory,
unpublished measurements.

4, L. J. Wittenberg, Mound Laboratory, Miamisburg, Ohio.
Oscillating-cup viscometry.

5. G. J. Janz et al., ""Molten Salt Data. Electrical Conduc-
tance, Density and Viscosity,;" Technical Bulletin Series
Rensselaer Polytechnic Institute, Troy, N. Y., July 1964,
p. 79.
11

s THERMAL CONDUCTIVITY

J. W. Cooke

Thermal Conductivitya

 

 

Salt in watt/(cm-OC) Uncertainty
Fy 0.01," > + 257
R, 0.01, " >t 25%
F, o.oosab > 1 25%
Fy 0.007," >t 25%
L,B 0.010 + 10%
C, 0.005, + 50%
C, 0.005, + 50%
a

As a first approximation, the temperature dependence of
thermal conductivity may be neglected. Although the
"thermal conductivity of molten salts does vary somewhat
with temperature, uncertainties in measurements at a
given temperature are usually greater than the tempera-
ture dependence over the whole range of temperature
(usually an interval of 200°C).

bBefore assuming anything about the relative values of

the four fuel melts, please read the caveat in the
Discussion.

Sources of Data and Methods of Estimation

 

Salts F, - F,: Estimated by means of a theoretical
expression derived by Rao1 and adapted to molten salts by
Turnbull.2 The expression is

T 1/2 2/3

k (in w em™ ©C!') = 11.9 x 107> 'm  Pm

(M/n)'?:E

where_Tm = melting point (OK), Py = liquid density in g cm™? at

o T,» M = average molar weight and n = average number of discrete
12

ions per molecule. Part of the expression,

11.9 x 103 Tml/2 o173/ u/ny %6

is a good approximation to the average maximum Debye lattice
frequency for single ionic salts.Z It was found for eleven
melten mixtures (nitrates or chlorides) that the above
expression agreed with experimental results, on the average,
to within 15%. For two fluoride melts, one LZB,3 the other,
LiF-BeF, -ThF, -UF, (71.2-23-5-.8 mole %),° the theoretical
expression yielded values approximately 25% less than experi-
mental. Note that the latter is very similar in composition
to F, .

In applying the theoretical expression the liquidus tem-
perature was substituted for Tm; in computing n, the following
ions were assumed: Li+, F, (BeF,)?%", (ThFS)_I, (UFS)'I.
Assumption of the more plausible ions, (ThF,)™® and (UF,)"3
leads to a lower and less reliable estimated thermal conduc-
tivity. Also, 15% was added to the estimated value because of
the previously noted discrepancy for the cases of the two
similar fluoride mixtures.

L,B: Measured’

C;, C: Very preliminary measurement3 on C, agrees with

the theoretical expression.
Discussion

The relative conductivities of the four fuel mixtures,

Fy-F,, are not more reliable than the absolute values. The

tabulated condubtivities were obtained from a theoretical
13

equation that was greatly extended to apply to these mixtures.
The dearth of accurate experimental data prevents adequate
testing of the extended theoretical expression either absolutely

or relatively.

References

1. M. Rama Rao, Indian Journal of Physiecs 16, 30 (1942).

Z. A. G. Turnbull, Australian Journal of Applied Science 12,
324 (1961).

3. J. W. Cooke, Oak Ridge National Laboratory, unpublished

experimental results. The method of measurement is given
on p. 15 in Proceedings of the Sixth Conference on Thermal

Conductivity, Dayton, Ohio, Oct. 19-21, 1966,

 
14

ELECTRICAL CONDUCTIVITY

G. D. Robbins

Salt Specific Conductivity - Temperature Equation Uncertainty

 

« in (ohm-cm)™', t in °C
F; k = 1.72 + 8.0 x 103 (t-500) + 20%
F, = 1.63 + 7.3 x 10~3 (t-500) + 20%
F, = 1.66 + 6.4 x 10-3 (t-500) + 20%
F, = 1.94 + 7.1 x 1073 (t-500) + 20%
L,B = 1.54 + 6.0 x 103 (t-500) + 10%
C, = 2.7 + 13 x 1073 (t-500) + 50%
C, = 1.92 + 2.6 x 10™3 (t-500) + 20%

Sources of Data and Method of Estimation

 

For 6 salts « was estimated empirically from data on related
or analogous salt melts. Often the assumptions employed were not
those which seemed physically most reasonable, but those which
resulted in the most self-consistent correlation of the data. .
Therefore, estimated k's are believed to have relatively large
uncertainties. The number of significangt figures in the equations
for « vs. t are not meant to contradict the listed uncertainties,
but rather are intended to show differences between salt mixtures
whose conductivities are predicted to be very similar.

Salts F;, - F;: The following equations were employed in

 

these estimates:

M

 

— e
A.e Ke.—-——
Po
T, (°K)
o - © _
Tliquidus (°K)
_ L L
Mo XLifLiF * Etnr, Mnr, * #%Ber, MBer, s
15.

e Ag = e€aquivalent conductivity at a corresponding temperature o
Kg = specific conductivity at ©
Po = density at ©
Me = equivalent weight of a mixture
M = formula weight of a component
X = mole fraction
X' = equivalent fraction

At several values of O smoothed curves of Ag VS thF4 were
obtained from conductivities of the system LiF-ThF, measured by
Brown and Porter,1 Ligquidus temperatures reported in references
2 and 3 were used in calculating ©. Similar curves for LiF-BeF,
were derived by plotting the experimental results for a single
composition (66 mole % LiF)4 and assuming that the variation of Ag
with X' in the LiF-BeF, system was equal to that in LiF-ThF,.

(For these estimates UF, was treated as indistinguishable from
ThF, .) The equations of « vs. t given above were then derived
by assuming that Ae is additive in X%hF4 and Xéer for a given

concentration of LiF.

L,B: Preliminary measurements.4

C,: The rati AE AE appeared relativel onstant in

2 io aI/ [ pp relatively c

the range © = 1.05 - 1.20 (data for Nal and KI from ref. 5).

Assuming that = specific conductance
& Aonapr, Poxpr, ~ Dewar’Mexr’ SP © '

data of Winterhager and Werner6 for KBF, were combined with

density estimates for KBF, and NaBF47 to obtain values of

AGNaBF4 vs. © (liquidus temperatures, from reference 8).
16

C;: Specific conductivity data in the range 47 to 77 mole

? were combined with those calcu-

% NaBF, in the NaF-NaBF, system
lated for pure NaBF, (see C,) to interpolate « for the composi-
tion NaBF,-NaF (92-8 mole %). The large uncertainty listed

reflects a lack of confidence in the data reported in reference

9.

Discussion

Specific conductivity is determined from resistance measure-

ments according to the relation
1
k = — (g/a)
\“‘

where (4/a) is the cell constant. For a given apparatus and

set of experimental conditions, the measured value of resistance
can vary with the frequency of the applied potential wave form.lo
The values of ¢ listed above are valid for resistance extra-
polated to infinite frequency (denoted as R®). Thus predicting
the resistance of the melt which will be measured in a particu-
lar experimental arrangement not only requires a value for

conductivity «, but also presupposes a knowledge of the

frequency dispersion characteristics of the measuring device.
17

REFERENCES
1. Brown, E.A. and B. Porter, U.S. Bureau of Mines Report of
Investigations 6500 (1964).

2. Thoma, R.E., H. Insley, B. S. Landau, H. A. Friedman, and
W. R. Grimes, J. Phys. Chem. 63, 1266 (1959).

 

3. Thoma, R. E., et al, ibid., 64, 865 (1960).

4. Robbins, G. D. and J. Braunstein, Molten Salt Reactor
Program Semiannual Progress Report for Period Ending
February 29, 1968, ORNL-4254.

 

 

 

5. Yaffe, I. S. and E. R. Van Artsdalen, J. Phys. Chem.,
ég, 1125 (1956).

 

6. Winterhager, H. and L. Werner, "Forschungsber. des
Witschafts u. Verkehrsministeriums Nordrhein - Westfalen,
No. 438, 1956.

7. Cantor, S., this report.

8. Bartomn, C. J., L. 0. Gilpatrick, J. A. Bornmann, H. Insley,
and T. N. McVay, Molten Salt Reactor Program Semiannual
Progress Report for Period Ending August 31, 1967,
ORNL-4191, p. 158.

 

 

9. Selivanov, V. G. and V. V. Stender, Russian J. Inorg. Chem.,
4, 934 (1959).

 

10. Robbins, G. D., "Electrical Conductivity of Molten Fluorides.
A Review,'" ORNL-TM-2180, March 26, 1968.
 

PHASE TRANSITION BEHAVIOR

Type of
Salt Transition
Liquidus
Fy
Solidus
Liquidus
F,
Solidus
Ligquidus
F, .
Solidus
Liquidus
Solidus
Peritectic
L,B ,
Solidus
¢ Eutectic
Solid-Solid
C; Melting Point
Solid-Solid
a.

18

R. E. Thoma

Temp .
(°C).

500+5

 

444+5

500+5

4445

480+£5

440°

500+£5

448+£5
458+1
360+£3

3851
2451

407+1
245+1

Crystallization Sequence
at Equilibrium

 

Lig = LiF + L,T® + Lig
Btwn 500-444: LiF+L,T+Liq
LiF+L; T+Ligq = LiF+L;T+Li, BeFy

Ligq = LiF + Ligq
Btwn 500-495:
Btwn 495-444:
Same as for F,

LiF + Liq
LiF+L;T+Liq

Lig = L,T + LT° + Ligq
Btwn 480-448: L;T+LT+Lig
Btwn 448-440: L,T + Liq
L;T + Liq = LyT + L,B

Liqg #=LTzd + Liq

Btwn 500-495: LT, + Liq
Btwn 495-490: LT, +LT+Liq
490: LT, +LT+Liq = L;T+Liq
Btwn 490-448: LT + Lig
Lig + LyT = Li,BeF, + L;T

Liq = Li,BeF, + Liq
Btwn 458-360: Li,BeF,+Liqg
Li,BeF,+Ligq = Li,BeF, +BeF,

Liq = NaBF, (cubic) + NaF

NaBF, (cubic) +NaF- ¥ NaBF, (or-
thorhombic) + NaF

Ligq == NaBF, (cubic)

NaBF, (cubic) = NaBF, (ortho-
rhombic)

L, T is an abbreviation for the solid solution, Li; (Th,Be)F,,
shown as the peppered triangle in the accompanying phase

diagram of LiF-BeF,-ThF, system.

LT is the abbreviation for LiThF;.

No precision has been assigned because this temperature
has not been experimentally established.

LT, is the abbreviation for LiTh,F,.
19

Sources of Data

 

Phase equilibria in the system, LiF-BeF,-ThF; - see next
page.

Phase equilibria in the system, LiF-BeF, - R. E, Thoma,
H, Insley, H. A. Friedman, and G. M. Hebert, Journal of
Nuclear Materials 27, in press 1968.

Phase equilibria in the system, NaBF,-NaF - C, J. Barton,
L. O. Gilpatrick, et al,, MSRP Semiann. Progr. Rept. Feb. 29,
1968, USAEC Report 0RNLw4254. The phase diagram is given

on page 21.
 

    

TEMPERATURES IN °C
COMPOSITION IN maois %

 

 

 

 

 

 

 

'X‘ .
BLIFsThF, / *
&73 f(..’;
N X

 

 
 
 
 

   

 

auFew, P-a88

Tha LiF ~BaF, - ThF, System.

 
  
  
  
 
  
     

: -_‘vfi‘.@.uvmuufififih‘

REF. J. PHYS. CHEM., 64, 883 ({580}

ORNL-DWG 88-24a2

580,

e 5\
\7
'e'e'*'e"‘*“"e'e.
wn‘x“flfi'i's‘&'fluv‘uuu
W % % W3 W
AVAVAVAVAVAVAVAVA' m

k-237

 

0¢
TEMPERATURE (°C)

ORNL-DWG 67—-9423A
1000 ¢

900 \#

 

 

 

800 ~

700 e
500 N
500 - \

 

 

 

 

400

 

 

 

 

300

i Tttt

NaF 20 40 60 80 NaBF
NaBF, (mole %)

The System NaF —NaBF,.

 

 

 

 

 

 

 

 

 

 

 

 

 

12
22

HEAT CAPACITY (at constant pressure)

 

A. S. Dworkin

 

 

 

Salt Cp in cal. g=! °c-'; t in °C  Uncertainty
F, liquid 0.34 + 4%
solid 0.22 + 12.7 x 1075 t + 10
F, liquid 0.39 + 4
solid 0.27 + 12.7 x 10”% ¢t + 10
F; liquid 0.33 + 4
solid .21 + 12.7 x 107° t + 10
F, liquid 0.33 + 4
solid 0.2 + 12.7 x 1075 t + 10
L,B liquid 0.57 + 3
solid 0.317 + 3.61 x 10™% ¢t + 3
C; liquid 0.360 + 2
solid (243-381°C) 0.34 + 3
solid (25-243°C) 0.23 + 5.8 x 107 t + 6
C, liquid 0.36 + 2
solid (243-406°C) 0.33 + 3
solid (25-2439C) 0.23 + 6.0 x 107% t + 6
Sources of Data and Methods of Estimation
Salts F; - F,: Liquid heat capacities were estimated by
assuming mole-fraction additivity and assigning 16, 24, and 44

cal mole™! ©C-1 for the respective contributions of LiF, BeF,,
and ThF,. The heat capacities for the solids were estimated by

assuming that (a) temperature coefficient and (b) difference in

Cp between liquid and solid are the same as that measured for

LiF-BeF, -ThF, (72-16-12 mole %) .-

L,B: Liquid Cp is the average of two independent sets of

——

2
measurements. Hoffman

and Payne3 obtained 0.56 cal g-! Oc-!. The solid heat capacity

obtained 0.577 cal. g!

O

C-!; Douglas
23.

s is that of Douglas and Payne.
Cy Measured1
C,: Meaéured}, Agrees within experimental error with
that derived from C, by subtracting enthalpy contribution of NaF*
assuming negligible heat of mixing between NaBF, and NaF.
Discussion
The values of 16 and 24 cal mole~! ©C-! were chosen for
the respective Cp contributions of LiF and BeF, because 8 cal
(g-atom) ™! OC"1 is the average observed for alkali and alkaline
earth halides.” The Gy of 44 cal mole™ °c-! for the contribu-
tion of ThFy; was assumed from the average value of 8.8 cal
(g-atom)~! ©C-! for lanthanide halides.6
The validity of using the indicated additive contributions

for estimating liquid heat capacities was checked by comparing

with measured values of three related salts:

Salt Mixture Estimated qg Measured Qp References
L,B 0.57 cal g-tocC-! 0.57 2,3
LiF-BeF, -ThF,

72 - 16 - 12 m % 0.32¢ 0.324 1
LiF-ThF,

75 — 25 m % 0.24 0.25 7
24
References

A. S. Dworkin, Oak Ridge National Laboratory, unpublished
measurements.

H. W. Hoffman and J. W. Cooke, Oak Ridge National Labora-
tory, unpublished measurements.

T. B. Douglas and W. H. Payne, Natl. Bur. Std. Report
No. 8186, Washington, D. C., pp. 75-82.

K. K. Kelley, U. S, Bureau of Mines Bulletin 584, (1960)
p. 171.

S. Cantor, Reactor Chem. Div., Ann. Progr. Rept. Dec. 31,
1965, ORNL-3913, pp. 29-32.

A. S. Dworkin and M. A. Bredig, J. Phys. Chem. 67, 697
(1963); 67, 2499 (1963).

R. A. Gilbert, Oak Ridge National Laboratory, unpublished
nmeasurements.
........

25

HEAT OF FUSION

A. S. Dworkin

 

 

Salt AHfusion (cal g~1) Uncertainty
F, 62 + 10%
F, 67 + 15
F, 58 + 15
F, 63 + 15
L,B 107 + 3
G, 31 +
C, 29 +

AH of solid transition (cal g~t)
C 14.5 (at 243°C) + 2%
C, 14.7 (at 243°C) L 2

Sources of Data and Methods of Estimation

 

Salts F; - F,: Although there is no isothermal heat of

 

fusion, estimations were made as if all the melting (or
freezing) occurred at 500°C. The salts were treated as
additive mixtures of the components, Li,BeF,, Li,ThF,;, and
LiF or ThF,. Li,BeF,; was considered to be "formed" first
from the BeF, present and the appropriate quantity of LiF.

The remainder of the mixture was then considéred to consist
of Li,ThF, and either LiF or ThF,, whichever was 'in excess."
For example, for 1 mole of salt F,, .16 moles of BeF, and .32
moles of LiF form .16 moles of Li,BeF, while..1ll moles of ThF,
and the remaining .41 moles of LiF give .11 moles of Li,ThF,
and .08 moles of LiF. The estimation is then made on the basis

of .16 moles Li,BeF,, .11 moles ThF, and .08 moles LiF.
26

The following heats of fusion were used in making the =
estimations:

Li, BeF, 10,600 cal mole~! (ref. 1)

Li; ThF, 13,960 cal mole~! - (ref. 2)

LiF 6,470 cal mole-! (ref. 3)

ThF, 11,000 cal mole™! estimated by

assuming the entropy of fusion
is the same as that of UF, (ref. 4)

L,B: Measured.l
C, and C,: Méasured;5 .C, agrees within experimental

error with that calculated by subtracting the .contribution
of the heat of fusion of NaF6 from C, .

Discussion
Although the assumptions used in estimating AHfusion
for salts F; - F, are highly intuitive, it is encouraging to

note that the estimated and measured7 AH are respec-

fusion
tively 57.5 and 59 cal g~! for the salt mixture LiF-BeF, -ThF,
(72-16-12 mole %) .

For salts F; - F4, to obtain the heat necessary to convert
the solid at the solidus temperature fo the melt at the
liquidus temperature, an additional 10 to 15 cal g-! should
be added to the above listed heats of ffision. For convenience
in calculating the quantity of heat necessary to raise the
salt from room temperature to any desired temperature, the

following heat content equations (based on measurements) are

included:
27

LiF-BeF, -ThF, (72-16-12 mole %) - ref. 5
Solid: H ~H;s; (cal g=l) = -5.28 + .207t + 6.33 x 10-5t%;

(25 - 440°0)

Liquid: H,-H,, (cal g=!) = 11.34 + .324t (500 - 750°C)

t

LiF-BeF, (66-34 mole %)
Solid: H -H (cal g~1)

i

0.3179t ~.1.806 x 107%t?;

0oC o
(0 - 472°C) - ref. 1

(cal g=') = 32.632 + 0.561t; (472 - 600°C) -
ref. 1
33.62 + 0.577 (t=-30); ref. 7

Liquid: Ht'HOOC

I

H -H;p (cal g™)

NaBF, ~NaF (92-8 mole %) ref. 5
Solid: H,~H,; (cal g™') = -5.90 + .230t + 2.90 x 107*t?;
(25 - 243°0)
H -H,5 (cal g=') = 0.40 + .337t; (243 - 381°C)

Liquid: H,-H,; (cal g™') = 22.1 + .360t; (381 - 600°C)

References

1. T. B. Douglas and W. H. Payne, Natl. Bur. Std. Report

No. 8186, Washington, D. C., pp. 75-82.

2. R. A. Gilbert, J. Chem. Eng. Data, 7, 388 (1962).
3. T. B. Douglas and J. L. Dever, J. Am. Chem. Soc. 76,

—

4826 (1954).

4, E. G. King and A. U. Christensen, U. S. Bureau of Mines

Report of Investigations 5709, 1961.

5. A. S. Dworkin, Oak Ridge National Laboratory, unpublished

measurements.

6. K. K. Kelley, U. S. Bureau of Mines Bulletin 584, (1960)

p. 171.

7. H. W. Hoffman.and J. W. Cooke, Oak Ridge National Labora-

tory, unpublished measurements.
 

28

DENSITY OF LIQUID

(S. Cantor)

Density-Temperature Equation

o (in g/cm3)

 

 

salt t (in ©¢) Uncertainty
Fy p = 3.628 - 6.6 x 10™% t 3%

F, = 3.153 - 5.8 x 10™* t 3

F, = 3,687 - 6.5 x 107* t 3

F, = 3.644 - 6.3 x 107 t 3

1,B = 2.214 - 4.2 x 107 t 2

C =2.27 - 7.4 x 107% t 5

C, = 2.26 - 7.4 x 107 t 5

Sources of Data and Methods of Estimation
Salts F, -~ F, - Estimated by additivity of molar volumes

(see Ref. 1).

LiF
BeF,

Th¥, a

The following molar volumes were used:

 

600°C 800°C
13.411 cm? 14.142 cm?
23.6 24 .4
nd UF, 46.43 47.59

 

Ref.

 

2
1,3

2

Salt L,B - Three experimental determinations have been

reported; refs. 5 and 6 were over a wide temperature range

with the densities of

ref. 6 averaging 3% higher than ref. 5.

Reference 4 reports densities at 64900 which vary from 1.87

to 2.02 g ecm™3,

The density-temperature equation given above
29

s was derived from additive molar volumes; this equation yields

densities that are approximately the average of the densities
of refs. 5 and 6.

Salt C; = Preliminary pyknometric measurements.7

Salt C, - The relatively small concentration of NaF in
C, would be expected to increase the density slightly over
that for 'pure" NaBF,. The density-temperature equation was
calculated by subtracting the contribution of NaF (ref. 1)

from the molar volume of C;.

References

1. 8. Cantor, Reactor Chem, Div., Ann, Progr. Rept. Dec. 31,
1965, USAEC Report ORNL-3913, pp. 27-=29.

2. D. G. Hill, S. Cantor, and W, T, Ward, J. Inorg. Nucl.
Chem. 29, 241 (1967).

3. C. T. Moynihan, S. Cantor, unpublished measurements at
Oak Ridge National Laboratory, 1966.

4, MSR Program Semiann. Progr. Rept. Aug. 31, 1965, USAEC
Report ORNL-3872, p. 31.

5. B. C. Blanke et al., "Density and Viscosity of Fused
Mixtures of Lithium, Beryllium and Uranium Fluorides,"
USAEC Report MLM-1086, Dec. 1956, p. 18.

6. B. J. Sturm and R. E. Thoma, Reactor Chem. Div. Ann.
Progr. Rept. Dec. 31, 1965, USAEC Report ORNL-3913,
pp. 50-=51.

7. 8. Cantor and J. Bornmann, unpublished measurements at
Oak Ridge National Laboratory, 1968.
30

EXPANSIVITY (VOLUME COEFFICIENT OF THERMAL EXPANSION)

 

 

S. Cantor

Salt Estimated Value at 600°C2 Uncertainty
F, 2.0, x 107*/9C 25%

F, 2.0, 25

F, 1.9, 25

Fy 1.9, 25

L,B 2.1, 20

c, 4., 40

c, 4., 40

a .

For estimating the expansivity at other temperatures,
please substitute in the appropriate density-temperature
equation. (see discussion below).

Sources of Data and Methods of Estimation

 

The expansivity is defined as

1 98V
a = — (—
where V, T and P are volume, temperature and pressure. Since

density is inversely proportional to volume, the expansivity

is usually derived from density-temperature data:

o)

=£ (P ordinarily one atm.)

R
il
|
|
o

Most density data for liquids are linear with and decrease
with temperature, i.e.,

po and a are constants; t is usually in degrees Celsiwus. Thus, e
31

g expansivity is very simply
a
o = 2 (2)
P

The tabulated expansivities are consistent with the
corresponding density-temperature equations in the "Density
of Liquid" Section of this report, To calculate the expansivity
for any temperature, substitute in equations (1) and (2). As a
rough approximation, the expansivity is one half to one third
of the temperature coefficient of density as given by the

constant a in eqn. (1).

References

Same as for the '"Density of Liquid" section, page 29.
32

COMPRESSIBILITY (ISOTHERMAL)®? s
S. Cantor

Compressibility-Temperature Equation

Bp in cm?dyne~!, T in °K

 

 

I

F, Bp = 2.3 x 107'% exp (1.0 x 107 T)

i

C, BT 9.0 x 10712 exp (1.6 x 107% T)

The compressibilities pertain to the liquid and are all

estimated; the uncertainty is a factor of 3.

 

Zfsothermal compressibility is a function of pressure
as well as temperature. The tabulated equations are
less reliable at higher pressures (>50 atm).

Methods of Estimation

 

Salts F,-F,, L;B: Estimated empirically from the com-
pressibility-temp. equations of LiF and Li, SO; (see ref. 1).

C, and C,: Assumed to be slightly more compressible
than Nal (see ref. 1).

Reasonable values derived for Cp/CV and for sonic veloc-
ities (see Appendix A of this report) lend support to these

estimated compressibilities.

References

1. S. Cantor, Reactor Chem. Div. Ann. Progr. Rept. Dec. 31,

 

1966, ORNL-4076, pp. 24-25.
33

VAPOR PRESSURE
S. Cantor

Pressure-Temperature Equation Uncertainty

 

 

Salt@ o
(P in torr, T in “K) in Pressure
Fy
v log P = 8.0 - 10, 000 A factor of
2 ' T fifty from
F, 500-700°C
Fy
I,B log P = 9.04 - 19%299 A factor of
ten from 500-
700°C
b
¢, log P (of BF, vapor) = + 10% from
9.024 - 22720 400-700°C
’ T
C, Pressure of BF, depends on

amount of salt and on vapor
volume (see Discussion below)

a
In no case is the composition of the vapor congruent
with the composition of the melt,

bThe pressures given by the equation are those in

equilibrium with a melt whose composition is fixed
at NaBF,-NaF (92-8 mole %).

Sources of Data and Methods of Estimation
Salts F,-F,: Estimated empirically from vapor pressure
data of the LiF-BeF, systeml and of LiF-UF; (73-27 mole %mz
Although the uncertainty is relatively large, please note that
the vapor pressures for the 500 - 700°C temperature range are
quite low (between 107? and 10~5 torr).

IL,B: Estimated from data in the LiF-BeF, system.z

 
34

Cy: Experimentally determined.3

Discussion - The Dissociation Pressure of NaBF,

When NaBF,; is thermally equilibrated at a temperature
above its melting point the following dissociation occurs:

NaBF, () = NaF(z) + BF;(g) (1)

The dissociation product, NaF, dissclves in the NaBF,. The
system described by the above equation is bivariant; thus,
a constant partial pressure of BF,; above the melt requires
that the temperature and the melt composition both be
constant. For reaction (1) the BF, pressure is related to

the composition of the melt by the equation:

a
K NaBF, (2)

P =
BF
3 aNaF

where K is the equilibrium constant and a; is activity. The
temperature dependence of K has been derived from experimental
data3 and is given by

-29,800 + 26 .41

RT (in °K) R

 

1n K (in atm) = (3)

29,800 cal and 26.41 cal (°k)~! are the enthalpy and entropy
of the reaction; R, the gas constant, is 1.98717 cal (9K)-!
(g-mole)~!}.

A consequence of the bivariance of the NaBF,-NaF system
is that the equilibrium BF; vapor pressure is difficult to
predict for melts in which the concentration of NaBF,; is very
large (>98 mole %). For these concentrations, aNaBF4 is

virtually unity, but ANaF is very small (<0.1); hence, by i
equation (2), P

35

BF tends to be quite high. Thus for any
3

experiment in which crystalline NaBF,; is encapsulated, the

temperature of the sample should be kept as low as necessary

or else sufficient vapor space should be included so as to

permit the dissociation reaction (1) to occur.

1.

References

5. Cantor, D. S. Hsu, and W. T. Ward, Reactor Chem. Div.

 

Ann. Progr. Rept. Dec. 31, 1965, ORNL-3913, pp. 24-6.
S. Cantor, Reactor Chem. Div. Ann. Progr. Rept. Dec. 31,

5. Cantor, C. E. Roberts, and H. F. McDuffie, Reactor Chen.

 

Div. Ann. Progr. Rept. Dec. 31, 1967, ORNL-4229, pp. 55-57.

 
36

SURFACE TENSION

J. W. Cooke, S. Cantor

Surface Tension-Temperature Equation S
Uncertainty

 

 

 

Salt v in dynes/cm, t in °C
Fy
Fa
F, y = 260 - 0.12 t +30,-10%
Fy
L,B
C, v = 130 - 0.075 ‘t * 30%
C, v = 120 - 0.075 t + 25%
Sources of Data and Methods of Estimation

Salts F,-F,, L,B: Estimated primarily from maximum bubble

pressure measurements on NaF-—Ber,1 LiF—BeFZ—ThF4—UF4,2 LiF,3

and ThF43 melts. Measurements at one temp. (4800C) of LiF-BeF,
(63-37 mole %94 by the ring method tends to support bubble pres-
sure values. Sessile drop measurements5 on L,B, on LiF-
BeF, -ZrF, -ThF, -UF, (70-23-5-1-1), and on other fluoride melts
would have led to higher predicted values. The higher
uncertainty in the positive direction expresses the possibility
that the sessile drop investigations might have yielded more
accurate surface tensions.

Salt C, and C,: Assumed that NaBF, (C,) and Nar®

exhibit (a) equal surface tensions at their melting points,

(b) equal temperature coefficients of surface tension. Then
37

s it was assumed that NaF in C,; increased the surface tension

over that of C, by 10%.

References

1. MSRP Quar, Progr. Rept, July 31, 1960, ORNL-3014, p. 83.

 

2. MSRP Quar. Progr. Rept. April 30, 1959, ORNL-2723, p. 42.

 

3. G. J. Janz and J. Wong, *"Molten Salts: Surface Tension
Data,' Troy, N. Y., Nov., 1967. Preprint of critical
review of surface tension data of single-salt melts for
the Standard Reference Data Project of the National
Bureau of Standards.

4. B. J. Sturm, MSRP Quar. Progr. Rept. Oct. 31, 1958,
0RNL“’2626, po 940

5. P. J. Kreyger, S. S. Kirslis, F. F. Blankenship,
Reactor Chem. Div, Ann. Progr. Rept. Jan, 31, 1964,
ORNL-3591, pp. 38-42.

6., R. B, Ellis, 'Surface Tension, Viscosity, and Raman
Spectra of Fused Salts,”" U. S. Atomic Energy Commission
Report ORO-2073-12, April 14, 1967, p. 3.
38

SOLUBILITY OF HELIUM, KRYPTON, AND XENON

G. M. Watson

Unit of solubility =~ 10~8 moles of inert gas per (cm° melt-atm).

 

 

 

Salt Temperature (°C)
F
1 -\ 500
F
2 600
F, }
700
Fy
800
LB J
500
600
¢y 700
800
500
600
¢, 700
800

He

 

6.6
10.6
15.1

20,1

44
52
60

52
61
69
75

Kr

 

0.13

.55

20
40
69
106

32
61
100
148

Xe

 

12
28
54
91

21
46
84
136

 

All solubilities are estimated;

is a factor of ten or greater.

 

the uncertainty

 
39

Sources of Data and Methods of Estimation

 

Sclubilities of noble gases were estimated by a method
originally proposed by Blander et al.l The expression used

in estimating the wvalues given above is:

- 1 : . : -18,08 ri~y
Kp BT (pclarization correction) exp ( RT >

moles of gas/(cm3 melt-atm)

=
I

r is the radius of the noble gas in Angstroms

v is the surface tension of the liquid in dyne cm_l

R in the pre-exponential term = 82,0561 cm3—atm (O‘K)m1
(g—mole)“l; in the exponential term R = 1.98717 cal
)"t (g-mole)”!

T is the absolute temperature in °k .

The numerical values for the radii and for the '"polarization

corrections' are:

 

He Kr Xe
Radius (Angstroms) 1.22 2.0 2.18
Polarization correction 0.14 1.0 1.34

 

The polarization corrections were determined empirically by
comparison of experimental and calculated noble gas solu-
bilities in NaF-ZrF, (53-47 mole %fl,z Na¥-KF~LiF eutectic,l’3
and LiF-BeF, (64-36 mole %9.3 The surface tensions used
appear in this report on page 36.

The rather large uncertainty in the gas solubilities can

be rationalized from the following considerations:
40

Experimenta,ll"3 and calculated (using the equation
given in the previous paragraph) solubilities agreed
to within a factor of three,

Calculated solubilities depend exponentially on the
assumed value of the surface tension; for the salts
of this report the surface tension, in each case

estimated, has a large uncertainty.

References

M. Blander, W. R, Grimes, N. V. Smith, and G. M. Watson,

J. Phys. Chem. 63, 1164 (1959).

W. R.
Chem.
G. MO

N. V.

Grimes, N. V. Smith, and G. M. Watson, J. Phys.
62, 862 (1958).
Watson, R, B. Evans III, W. R, Grimes, and

Smith, J. Chem. Eng. Data 7, 285 (1962).

S
41

SOLUBILITY OF BF; GAS

S. Cantor, G. M. Watson

Unit of Solubility - 10~ % moles BF; per (cm® melt-atm)

Temperature (°c)

 

 

Salt 500 600 700 800

Fl 3.4 1.1 0.44 0.19
F2 3.4 1.1 0.44 0.19
F3 2.8 0.95 0.39 0.20
F, 2.4 0.83 0.35 0.18
LZB 3.2 1.0 0.38 0.18
¢y

c See section on Vapor Pressures, page 33.

 

All solubilities are estimated; the uncertainty
is a factor of ten or greater. '

 

 

Sources of Data and Methods of Estimation

Solubilities of BF; were assumed to be analogous to
solubilities of HF. For LiF-BeF,-ZrF,-ThF,~UF, (65-28-5-1-1
mole %) the measured BF31 and HF2 solubilities both exhibited
negative temperature dependence (inert-gas solubilities in
fluoride melts are much smaller and show positive temperature
dependence). The ratio of BF; to HF solubility in the range

500-800°C for this melt was the multiple used to estimate the
42

BF; solubility in L;B from the measured values of HF solu-
bility.3

Solubility of HF in F;-F, was estimated by assuming the
same ''free fluoride' concentration dependence as had been
observed for LiF-BeF, mixtures.,* (For F,-F,, free fluoride
+ 3X

is defined as X, .. minus (2X ), where X is mole
LiF 4

BeF, MF
percent; for LiF-BeF, mixtures, free fluoride equals XLiF
minus ZXBer)' The BF; solubilities were then calculated
by multiplying the estimated HF solubilities by the same
ratios that were derived from the melt where both gas solu-

bilities had been measured.

References

1. J. H. Shaffer, W. R. Grimes and G. M. Watson, Nucl. Sci.
Eng. 12, 337 (1962).

2. J, H., Shaffer and G. M. Watson, Reactor Chem. Div. Ann.
Prog. Rept. Jan. 31, 1961, ORNL-3127, pp. 13-14.

3. P. E. Field and J. H. Shaffer, J. Phys. Chem. 71, 3218
(1967).

4. J. H. Shaffer and G. M. Watson, Reactor Chem. Div. Ann.

Prog. Rept. Jan. 31, 1960, ORNL-2931, pp. 31-32.

e

 
43

APPENDIX A

ISOCHORIC HEAT CAPACITY (C), cp/cv, AND SONIC VELOCITY

Ca

 

 

v
Salt Temp. cal cal cal p?
O O 0 O C /C -1
C g K (g-mole)k (g-atom) K p Vv (m sec ™)
; ggg 8.295 17.8 7.15 1.15 2620
1 .29 17.6 7.08 .1z 2560
700 0.288 1.7.5 6.97 l.1g 2480
500 0.337 16,9 6°98 1.1g 2850
F, 600 0.33, 16.6 6,88 1.17 2760
700 0.32g 16‘4 6.79 1.19 2670
500 0.289 18.5 7.2, 1.1, 2610
F3 600 0.285 18,5 7.15 1.1 2520
700 0.285% 18.1 7.0% 1,17 2LL0
n de o0 189 % T R
) .28 = 7. : 1.15 2530
700 OGQSM 18,5 7.03 1.1z 2Lho
500 o,&89 16.2 6.91 1.17 2L20
L2B 600 o,u82 15.9 6.8l 1.1g 3310
700 0,475 1,5.7 6.72 1.2, 3200
500 0.31, 52.6 5.7}, 1.15 1400
C, 600 0.30g 325 5.6 1.17 1330
700 0.30g 3l.g 5.63 1.1g 1260
Theoretical CVC
cal mole"l(oK)ml
500 0,512 Bh,g 30.47 1.16 1400
C, 600 0.30g 35.8 30.92 1.17 1330
700 0.30) 35.5 31.46 1.19 1260

 

a. Calculated from the equation,

P
C.=C - %L yhere q is expansivity; p, density; B isobhermal

V. P PP compressibility. T
b. Calculated from the equaticn,
M= (ET;E**)l/Q where p is sonic velocity.
VP

c. Calculated by assuming

g Cy = 6.R (harmonic oscillation of 2 ions) + 1.5R (free rotation of

BFL ion) + Vibrational*heat capacity of BFi#.

* Vibraetional frequencies obtained from K. Nakamoto, Infrared Spectra of
Inorganic and Coordination Compounds, John Wiley and Sons, N. Y., 1963, p. 106.
44

APPENDIX B

THERMAL DIFFUSIVITY,® KINEMATIC VISCOSITY,® AND PRANDIL NUMBER®

 

Salt Temp. Therm. Diffy. Kin. Vise. Prandtl
(°c) (cm? sec™t) (e gec”l) Number
500 2.153 x 1072 6.9 x 1072 32.3
By 600 2.17 3.75 17.5
700 2.22 2.2 10.5
500 2.35 x 1073 7.1lw x 1072 30.4
Fa 600 2.4¢ 3.8 15.4
700 2.45 2.3, 9.5
500 1.7¢ x 1077 7.05 x 1072 39.,
Fi 600 1.8 3.7 20. 5
700 1.8¢ 2.2¢ 12.,
500 1.5, x 1077 8.9, x 1072 58.¢
F, 600 1.5 4.3z 27. 8
700 1.5 2.4y 15.,
500 2.0¢ x 1073 7.4 x 1072 35.¢
L,B 600 2.1, 4.3¢ 20.4
700 2.1g 2.8¢ 13.4
500 1.8, x 10-7 1.0, x 107% 5.4
o 600 1.8 0.6g 3.6
700 1.97 Oo5o 2¢5
500 1.79 x 1073 1.0, x 10-2 5.
Ca 600 1.8¢ 0.6g 3.9
700 1.95 Q.50 2.6

 

Calculated from the equations:

k
a X = 5
P ¥p
b, v =
P
c Pr = Y =

where k is thermal conductivity; p, density; Cp, specific

heat.

wvhere n is viscosity in poise (g ecm™ sec-?).

%
k
45

APPENDIX C

CONVERSION FACTORS

 

Multiply By To Obtain

Viscosity centipoise 2.419 Ib_/hr-ft
Thermal Conductivity watts/°Cecm 57.8 Btu/hr-ft-°F
Heat Capacity cal/gm°°C 1.0 Btu/lby- °F
Heat of Fusion cal/gm 1.8 Btu/lbp
Density gm/cm3 62.43 1bm/ft3
Compressibility em?/dyne  6.894x10" in 2/1b .
Pressure torr 0.019337 1bf/in2 (psia)
Surface Tension dyne/cm 6.85 x 107 lbg/ft

dyne/cm 2.203 x 107° 1b_/sec?
46

Composition of Salt Mixtures

 

 

Mole % Liquidus
Symbol LiF BeF, ThF, UF, Temp. (°C)
F, 73 16 10.7 0.3 5009 + 50
Fuel- F, 72 21 6.7 0.3 500° + 5°
Breeder o o
' +
Mixtures F, 68 20 11.7 0.3 480° + 5
Fu 63 25 11.7 0.3 5000 = 5°
Flush Salt L,B 66 34 - -- 458% + 1°
{present MSRE (peritectic)
coolant)
NaBF, NaF
Coclants C 92 8 3850 + 1°
(eutectic)
C, 100 - 4079 + 1°
(melting

point)

.............
b7

T

ORNL-TM~ 2316

INTERNAL DISTRIBUTION

1. R. K. Adanms 78. L. T. Corbin
2. G. M. Adamson 79. B. Cox
3. R. G. Affel 80. J. L. Crowley
4. L. G. Alexander 8l1. F. L. Culler
5. J. L. Anderson 82. D. R. Cuneo
6. R. F. Apple 83. J. M. Dale
7. C. F. Baes 84. D. G. Davis
8. J. M. Baker 85. R. J. DeBakker
g. S. J. Ball 86. J. H. DeVan
10. C. E. Bamberger 87. S. J. Ditto
11. C. J. Barton 88-92. A. S. Dworkin
12 H. F. Bauman 93. I. T. Dudley
13. S. E. Beall 94. D. A. Dyslin
14. R. L. Beatty 95. W. P. Eatherly
15. M. J. Bell 36. J. R. Engel
16. M. Bender 97. E. P. Epler
17 C. E. Bettis 98. D. E. Ferguson
18. E. S. Bettis 99. L. M. Ferris
19. D. S. Billington 100. A. P. Fraas
20. R. E. Blanco 101. H. A. Friedman
21. F. F. Blankenship 102. J. H. Frye, Jr.
22. J. 0. Blomeke 103. C. H. Gabbard
23. R. Blumberg 104. R. B. Gallaher
24, E. G. Bohlmann 105. R. E. Gelbach
25. C. J. Borkowski 106. J. H. Gibbons
26. G. E. Boyd 107. L. O. Gilpatrick
27. C. A. Brandon 108. H. E. Goeller
28. M. A. Bredig 109. W. R. Grimes
29. R. B. Briggs 110. A. G. Grindell
30. H. R. Bronstein 111. R. W. Gunkel
31. G. D. Brunton 112. E. D. Gupton
~32. D. A. Canonico 113. R. H. Guymon
33-62. S. Cantor 114. J. P. Hammond
63. W. L. Carter 115. B. A. Hannaford
64. G. I. Cathers 116. P. H. Harley
65. 0. B. Cavin 117. D. G. Harman
66. A. Cepolino 118. W. O. Harms
67. F. H. Clark 119. C. S. Harrill
68. W. R. Cobb 120. P. N. Haubenreich
69. C. W. Collins 121. R. E. Helms
70. E. L. Compere 122. P. G. Herndon
71. K. V. Cook 123. D. N. Hess
o 72. W. H. Cook 124. J. R. Hightower
"""" J. W. Cooke 125. M. R. Hill
126.
127.
128.
126G,
130.
131.
132,
133.
134.
135.
136.
137.
138.
139.
140,
141.
142.
143.
144,
145,
146.
147,
148.
149.
150,
151,
152.
153,
154,
155,
156.
157,
158.
159.
160.
161.
162.
163.
164.
165.
166.
167.
168.
169.
170.
171.
172.
173.
174.
175.
176.

v—:}t:fl:u.:mi;:fqt-oom%:::wmaodcq:umwwgmmmmguuouqbgmmflozgow*usmr-amvuwmm

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cC

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Hitch
Hoffman
Holmes
Holz
Horton
Hudson

nouye

Jordon
Kasten
Kedl
Keller
Kelley
Kelly
Kennedy
Kerlin
Kerr
Kirslis
Koger
Krakoviak
Kress
Krewson
Lamb

Lane
Lawrence
Lin
Lindauer
Litman
Llewellyn
Long
Lundin
Lyon
Macklin
MacPherson
MacPherson
Mailen
Manning
Martin
Mauney
lain
McClung
MeCoy
McDuffie
McGlothlan
McHar gue
McNeese
McWher ter
Metz
Meyer
Moore
Moulton
Mueller

418

177.
178.
179.
180.
181.
182.
183.
184.
185.
186.
187.
188.
189.
190-194.
195.
196.
197.
198.
199.
200.
201.
202.
203.
204.
205,
206.
207.
208.
209.
210.
211.
212.
213,
214,
215.
216.
217.
218.
219.
220.
221.
223,
224,
225.
226-230.
231.
232.
234.
235.
236-220.
241.

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Nelms
Nichols
Nicholson
Nogueira
Qakes

atriarca

Perry
Pickel
Piper
Prince
Ragan
Redford

ichardson

Robbins
Rober tson
Robinson
Roller
Romberger
Rosenthal
Ross
Savage
Schaffer
Shilling

ap Scott

Scott
Seagren
Sessions
Shaffer
Sides
Skinner
Slaughter
Smith
Smith
Smith
Smith
Smith

piewak

Steffy
Stoddard
Stone
Strehlow
Tallackson
Taylor

erry

Thoma
Thomason
Toth
Trauger
Watson
Watson
Watts
49

242. C. F. Weaver 251. Gale Young
243, B. H. Webster 252. H. C. Young
244. A. M. Weinberg 253. J. P. Young
245. J. R. Weir 254. E. L. Youngblood
246, W. J. Werner 255. F. C. Zapp
247. K. W. West 256=-257. Central Research Library
248. M. E. Whatley 258-259. Document Reference Section
249. J. C. White 260-285. Laboratory Records (LRD)
250. L. V. Wilson 286. Laboratory Records -
Record Copy (LRD-RC)
EXTERNAL DISTRIBUTION

287-288. D. F. Cope, AEC-ORNL, R.D.T. Site Office
289. J. W. Crawford, AEC-RDT, Washington
290. C. B. Deering, AEC~ORO
291. A, Giambusso, AEC,Washington
292. W. J. Larkin, AEC-QORO
293. C. L. Matthews, AEC-0ORO

294-295. T. W. McIntosh, AEC, Washington
296. C. E. Miller, Jr., AEC, Washington
297. B. T. Resnich, AEC, Washington
298. H. M. Roth, AEC-0ORO
299, Milton Shaw, AEC, Washington

300. W, L. Smalley, AEC-ORO
301, R. F. Sweek, AEC, Washington
302~317. Division of Technical Information Extension (DTIE)