-. .r

J 3 7

W F 0

io 0 W 5

i ' f

\*# .

-.

FRACTIONAL

-

O A K RIDGE NATIONAL LABORATORY operated by

UNION CARBIDE CORPORATION NUCLEAR DIVISION

for the U.S. ATOMIC ENERGY COMMISSION

ORNL - TM-2596

4 3 COPY NO. -

CRYSTALLIZATION REACTIONS IN THF, SYSTEM LiF-BeFz-ThF4 1 R. E. Thoma and J. E. Ricci

ABSTRACT

Equilibrium and non-equilibrium crystallization reactions in the system LiF-BeFz-ThF4 are analyzed in relation to their potential application to molten salt reactor fuel reprocessing.

temperature range from the liquidus at 59OoC to the solidus at 35OoC are

described qmtitatively and in detail by means of ten typical isothermal

sections and by three temperature-composition sections. The implications of metastable fractionation'4n this temperature interval are discussed

as a possible feed control step in reductive extraction reprocessing of molten salt breeder reactor fuels.

Heterogeneous equilibria in the

NOTICE This document contains information of a preliminory nature and was prepared primarily for internal use a t the Oak Ridge National Laboratory. I t is subject to revision or correction and therefore does not represent o final report.

LEGAL NOTICE -- -

This report was prepared as an account of Government sponsored work.

nor the Commission, nor any person acting on beholf of the Commission:

A. Makes any warranty or representation, expressed or implied, with respect t o the accuracy,

completeness, or usefulness of the information contained in th is report, or that the use of ony information, apparatus, method, M process disclosed in th is report may not infringe

privately owned rights; or

6. Assumes any l iabi l i t ies wi th respect t o tha use of, or for damages resulting from the use of any information, apparatus, method, or pocess disclosed in th is report.

Neither the United States,

As used in the above, "person acting on behalf of the Commission" includes ony employee or contractor of the Commission, or employee of such contractor, to the extent that such employee

or contiactor of the Commission, or employee of such contractor prepares, disseminates, or

provides access to, any information pursuant to h is employment or controct wi th the Commission,

or his employment wi th such contractor.

r

3

CONTENTS

Abstract . . . . . . . . . . . ' . * " ' . . . " . ' * " ' * . ' ' * ' ' g

In t roduct ion . . . . . . . . . . . . . . . . Liquid-Solid Phase Reactions I n The System LiF-BeFa-ThFL , . . . -

P o t e n t i a l Application of F rac t iona l Czys ta l l iza t ion I n Chemical

Reprocessing . . . . . . . . . . . . . . . . . . . . . . . . .

c

Page 1

4

5

24

INTRODUCTION -- The ORNL Molten Salt Reactor Program is devoted to the development

of molten salt breeder reactors which employ mixtures of molten fluorides as core fluids. Until recently, the most promising approach to the development of molten salt breeder reactors appeared to be a two-

region reactor with fissile and fertile materials in separate fuel and

blanket streams. Thorium would be carried in the blanket salt, in a salt stream which would consist of a 7LiF-E3eF2-ThF4 mixture.

in chemical reprocessing have provided evidence recently that possibly the rare earth fission products can be separated from mixed

thorium-uranium salt by reductive extraction methods employing liquid bismuth. This development, along with other design developments, makes

possible a single-fluid breeder reactor, one which has greater simplicity and reliability than the two-fluid reactor. The fuel for the single fluid reactor would be composed of 7LiF, BeF2, ThF4, and 233UF4, and

might be expected to contain - 12 mole $ ThF4. and BeF2 concentrations is not complete, because the trade-off values of several significant factors have not yet been established. These include selection limitations imposed by the equilibrium phase behavior

of the LiF-BeF2-ThF4 system (233uF4 concentration will be only 0.2 mole $, and is therefore of little consequence in this connection), physical properties such as viscosity, vapor pressure, thermal conductivity, and the relations of LiF-BeFz-ThFb composition to the development of

chemical processes for removal of protactinium and the lanthanides.

Advances

3Pa and

Optimization of the 7LiF

Effective separation of the rare earth fission products from fluoride salt streams which contain thorium fluoride is the keystone to

development of semi-continuous reprocessing in single-fluid molten salt

reactors. Several methods for reprocessing spent LiF-BeF2-ThF4-UF4 fuels

are currently under investigation.

tractable for engj-neering development involves the selective chemical re- duction of the var'ious components into liquid bismuth solutions at about 6OO0C, utilizing multistage countercurrent extraction operations.

current status of engineering development of this process has been

The method which is regarded as most

The

described by Whatley et al.' protactinium by reductive extraction. A strong incentive then exists to remove the rare-earth fission products from the remaining salt. The most

nearly feasible approach to this separation seems to be their extraction

The initial steps remove uranium and

1

5

.- into bismuth even though the recycle volumes of extractant are

marginally acceptable. The efficiency of this separation step would

be greatly enhanced if the concentration of the rare earths in the salt mixture were increased by at least tenfold, and if the residual salt solutions were of a much lower concentration of thorium fluoride.

That the LiF-BeF2-ThF4 phase diagram4 shows the occurrence of low melting mixtures of low thorium fluoride content which are producible from MSBR single-core fluids by metastable crystallization has suggested the possibility that non-equilibrium fractionation reactions might be

exploited as a feed control step in the reductive extraction process. Because of its relative complexity, the unpublished version of the

LiF-BeFa-ThF4 phase diagram may experience less frequent or less

effective application in molten salt reactor technology than is warranted by the developments cited above. this report further detailed aspects of equilibrium and non-equilibrium

behavior in the system.

We therefore describe in

LIQUID-SOLID PHASE REACTIONS IN TKE SYSTEM LiF-BeFz-ThF4

Methods for interpreting polythermal and isothermal phase diagrams

are described extensively in an earlier report5 where the phase relation- ships in a number of fluoride systems were analyzed in detail. Interpre- tation of the equilibrium' behavior in the system LiF-BeF2-ThF44 (Figure 1) is somewhat more complex than for the systems analyzed because of the

occurrence of an unusual s o l i d solution which is produced as the compound 3LiF.ThF4 crystallizes from LiF-BeFz-ThF4 melts. nominal composition, 3LiFeThF4, precipitates as a ternary solid solution

which, at its maximum in composition variability (near the solidus),

is described by a composition triangle with apices at LiF-ThF4 (75-25 mole $), LiF-BeFz-ThF4 (58-16-26 mole $), and LiF-BeF2-ThF4 (59-20-21

mole $,).

single phase solid solution area: (1) a substitution of one Be2+ ion

for a Li ion with the simultaneous formation of a Th vacancy for every

four Be2+ ions substituted for Li

( 2 ) substitution of a single Be ion for a Li ion with the simultaneous

formation of a Li vacancy. Model (1) would afford a solid solution

The crystal phase of

Two substitution models may provide an explanation for the

+ 4+ 4- ions to provide electroneutrality and

2+ + +

3LiF.1

ORNL-LR-DWG 37420AR6 ThG 44t4

P 458 E i60

TEMPERATURE IN OC COMPOSITION IN mole To

526

BeF2 548

Fig. 1. Polythermal Projection of the LiF-EkF,-ThF4 Equilibrium Phase Diagram .

I - .

7

W limit in good agreement with the leg of the triangular area with the lesser ThF4 content whereas model (2) would give a line extending from

3LiFaThF4 toward BeFz-ThF4 (60-40 mole 4). which permits considerably higher ThF4 content than that found experi-

mentally. Accordingly, it appears that both models are simultaneously applicable for the crystallization behavior of 3LiF*ThF4 as it zqystallizes from LiF-BeFz-ThF4 melts.

been established (a study of the structure is currently in progress )

it w i l l be possible to appraise the validity of these models.

This is a limiting line

Once the crystal structure of 3LiFeThF4 has 6

Application of ternary phase diagrams to technology often requires

a knowledge of the identi-tlies and compositions of the various phases in

equilibrium at specific temperatures. by equilibrium phase diagrams. Typically, phase diagrams of ternary systems are presented as projections of temperature-composition prisms

on their basal planes. liquidus temperatures, equilibrium crystallization and melting reactions can be described in a quantitative manner.

sections is often valuable, particularly if the phase diagram is complex.

The chief feature of the isothermal section is that it provides informa- tion both about the identity and relative masses of coexisting phases.

Such information is represented

When such schematic representation includes

Here, the use of isothermal

The crystallization behavior of the 3LiF.ThF4 ternary solid solution

determines the composition sequence as LiF-BeFz-ThF4 melts are cooled. A series of equilibrium isotherms is shown in Figs. 2 to 11, which describe a11 the equilibrium reactions in the temperature interval from 59OoC to 35OoC, i .e,, the Liquidus-solidus interval of chief relevance

to the compositions which are likely to have application in molten salt reactor technology, and in which all 3LiFsThF4 solid solution melting- freezing reactions occur. Within this interval all the solid phases

of the system are involved, The equilibrium behavior of chief importance to us is described further by the temperature-composition sections, 3LiF-ThFq-2LiFaBeF2, LiF.ThF4-2LiF-BeF2, and LiF*2ThF4-2LiF*BeF2, shown

in Figs. 12-14 (schematic, not to scale).

8

-- a

E!

k 0

0

[II H

ORNL-DWG 68-f4678R

LiF- 2ThF4

LiF ThG

LiF

3LiF ThF4 ss

TEMPERATURE IN OC COMPOSITION IN mole '%

T = 57OoC

P 458 E 360

Fig. 3. Isothermal Section of the System LiF-BeF2-ThF4 at 570OC.

ORNL- DWG 68- 11679R

LiF - 3LiF l ThF4

LiF-k \ Li

2LiF l BeF,

3LiF l ThF,

TEMPERATURE COMPOSITION IN

IN “C mole %

\\\\\

848 2LiF l BeF2<001450 4007 400 450 500 P 458 E 360

Fig. 4. Isothermal Section of the System LiF-BeFz-'J!hFk at 562'C.

,E 526 BeF2 555

.

ORNL-DWG 68-11677R2

3LiF

-l LiF* 2ThFq

1 2LiF BeF,

TEMPERATURE IN OC COMPOSITION IN mole YO

BeF2 555

Fig. 5. Isothermal Section of the System LiF-BeFz-ThF4 at 49OOC.

ORNL- DWG 68 - 1 1680R2

TEMPERATURE IN O C COMPOSITION IN mole '70

BeF2 555

Fig. 6 . Isothermal Section of the System LiF-BeFZ-ThFb at 457OC.

,

LiF

ThF, 1111 ORNL-DWG 68-11675R

TEMPERATURE IN O C COMPOSITION IN mole %

BeF, 848 2LiF *BeF2’ 555

Fig. 7 . Isothermal Section of t h e System LiF-BeFz-ThF,: a t 447OC.

LiF 848

Thh t f t l ORNL- DWG 69 - 5297

TEMPERATURE IN OC COMPOSITION IN mole Ye

44OOC

2LiF - BeF2’

Fig. 8. Isothermal Section of the System LiF-BeFZ-ThF4 a t U O O C .

BeF 55g

ORNL-DWG 68-14674

LiF 2ThF4

TEMPERATURE IN OC COMPOSITION IN mole Yo

BeF2 555 / LiF

848 2LiF BeFz

Fig. 9. Isothermal Section of the System LiF-BeFz-ThF4 at 43OoC.

ORNL-DWG 68-If673 Thb 1111

LiF 848

LiF l 2ThFq

x

2LiF l BeF,’ 500

Fig. 10. Isothermal Section of the System LiF-BeFz-ThF4 at 43O'C.

BeF2 555

.

.

ORNL-DWG 68-11672

LiF 848

TEMPERATURE IN OC COMPOSITION IN mole %

8eF2 555

Fig. 11. Isothermal Section of the System LiF-BeF2-ThF4 at 350°C.

The isothermal sections included in Figs. 2 to 11 are drawn to scale and represent the experimental results which were the basis of the

4 previously published phase diagram. Composition-temperature relations

in the LiF-BeFZ-ThFL system for LiF concentrations greater than 50 mole $, are shown in detail in Fig. 15.

The straight lines appearing in Figs. 2 to 11 are tie-lines (or "conodes") connecting two phases which are in equilibrium. point P, as a point on such a tie-line joining points b and z, represents a mixture of the phases (or compositions) b and z with the mole fraction of b equal to the ratio of line lengths zP/zb.

In Fig. 16,

In the case of a mixture of three phases, such as the points a, b, c making up the total composition at point P (Fig. 16), the relative amounts of the phases a, b, c making up P may be determined as follows, with t h e three fractions defined as x of a, y of b, 1-x-y of c. Then:

(1) Graphically: extend the line bP to fix the point z on the

line ac. Then y = zP/zb, and x = (zc/ac) (1-y) . (2) Analytically: let the fractions of the components A and B

at each of the four points (a, b, c, P) be

Aa % Ac A.~7

Ba Bb 'P* Then by similar triangles, we have

Then BZ = % - (3% + BAz = Ba - CXAa + CXAz

Hence A = (B a - $) + p% - CXAa B - a :

Z

Then y = B - B Z

% - BZ

A A

A - A m d x = z - c (1 - y).

C a

-.

573

565

19

ORNL - DWG 69 - 5294

LIQ

L3Tss+ LiF + L2B T -3 ss

3 LiF. ThF4 (L3T)

P - 458O

P, - 444O

Fig. 12. The Section 3LiF*ThF4-2LiF-BeFz

c

20

ORNL-DWG 69-5295

-.

P-762O

P-597O

LT = LiF - ThF4 LT2 = LiF * 2ThF4 LT4 = LiF - 4ThF4 L2B = PLiF * BcF,

L la

LIQ+LT2

LIQ t LT

L I Q t LT + L,T,, . L I Q t L i F

+ LIO t L iF + L2B P-458O

P - 4 4 4 0

P-4330

Fig. 13. The Section LiF*ThF,!,-2LiF*BeF2

21

?-897'

?-762a

P-4480

OANL- DWG 69 - 5296

LT = L i F . T h F4 LT2= LiF. 2ThF4 LT4= LiF. 4ThF4 L2B = 2Li F Be F2

LIQ + LT2

/LIQ+ LiF

P-458O

ZLiF.BeF2 (12b)

Fig. 14. The SecCion LiF.2ThF4-2LiF.BeF2

22

ORNL-DWB (18-942A

TEYPERATUIKS IN *C COMPOSITION IN mob X

Fig. 15. Phase Diagram of the LiF-BeFz-ThFq System for Compositions 50 - 100 mole $ LiF.

23

ORNL DWG. 69-7559

c

Fig. 16. Schematic Drawing for Use in Calculating Relative Fractions of Coexisting Phases at Point P.

24

POTENTIAL APPLICATION OF FRACTIONAL CRYSTALLIZATION -- IN CHEMICAL REPROCESSING

Under equilibrium conditions, the crystallization end-point in three component systems such as in the LiF-BeFz-ThF4 system, depends on the "compatibility" or three solid phase triangles of the equilibrium diagram. As an example, compositions in the triangle LiF - 3LiF.ThF4- 2LiF eBeF2 have their crystallization end-point at the 444'C peritectic reaction point. LiF-BeFz-ThF4 mixtures does not follow the equilibrium crystallization

diagram exactly; instead, non-equilibrium crystallization proceeds characteristically by sub-cooling (i.e., delayed crystallization under

dynamic cooling), and by incomplete recombination of liquid and solid phases at the peritectic reaction points. Thus, liquids are produced from mixtures which are of interest to us, primarily those containing high concentrations of LiF, which are richer in BeF2 than their equilibrium counterparts, and which crystallize as described by the lower melting areas of the phase diagram. equilibrium fractionation is thus to produce liquid residues which are lower in ThF4 content than at equilibrium.

As noted previously: dynamic crystallization of

The consequence of non-

Let us examine the difference between equilibrium and non-equilibrium

crystallization behavfor of a liquid composition that would partially typify the reactions of MSBR salts.

BeF2-ThF4 (63-32-5 mole @, undergoes equilibrium crystallization. On complete solidification, the frozen salt w i l l consist of the three crystalline phases, 3LiFaThF4 ss, 2LiFoBeF2 and LiF.2ThF4 in proportions given by the position of point c in the corresponding triangle of Figs.

9, 10, and 11.

Suppose the composition c, LiF-

For non-equilibrium crystallization this triangle has no signifi-

cance. The non-equilibrium process consists of four consecutive steps,

seen on the basis of the following diagram:

25

LiF

Step (1): freezing starts at - 446OC for composition c, and the liquid travels on the solid solution liquidus surface to reach curve PI - P3 at some point R (at - 44OoC), while precipitating some solid

solution of composition between a and b, say a' as average. Step (2): liquid travels on curve Pl-P3, to reach P3 (433OC),

while precipitating a mixture of solia solution (of composition between b and s, say b' as average) and 2LIFoBeF2.

Step ( 3 ) : liquid travels on curve P3-E, to reach E(356') while precipitating mixture of LiF02ThF4 + 2LiFoBeF2.

Step ( 4 ) : liquid at E(356') freezes to mixture of LiF-2ThF4 + 2LiFaBeF2 + BeF2.

Qmntities involved for 1 mole of starting composition c :

26

Step (1): draw s t r a i g h t l i n e a ' c and extend it t o curve PI-P,,

t o f i x poin t a :

a

. Moles of l i q u i d reaching a = = m l ;

Moles of ThF4 p rec ip i t a t ed ( i n s t e p 1, or between 446 and 440')

a ' a

= x (1-ml) = p1, a ' i n which x = mole f r a c t i o n of ThF4 a t a ' , e t c .

a ' Step (2): d r a w s t r a i g h t l i n e b'-H, and extend s t r a i g h t l i n e JP3

back t o f i x point y on l i n e b'-H:

27

Moles of liquid reaching P3 = (ml) = m2;

Moles of ThF4 precipitated (in step 2, or between 440' and 433') YP3

- yH (ml-mz) = p2. - % ' b'H Step ( 3 ) : draw straight line DH and extend straight line P@

back to fix point z on the l i n e DH:

LiF

2LiF.BeF2 (=HI

ZP Moles of liquid reaching E = $ (m2) = m3;

Moles ThF4 precipitated (in step 3 , or between 433' and 356')

= 2 zH - 3 (-) DH (m2-rn3) = p3,

since x = 2/3. D Step ( 4 ) : moles ThF4 precipitated in this step (at 356')

= x - (PI + p2 + p3). C Thus, given the original composition c on the phase diagram as we

have it, one can make estimates regarding what happens in steps (1) and

(2), and these estimates fix what happens in steps (3) and ( 4 ) , for the

limit of non-equilibrium behavior. is never any interaction between precipitated solid and solution.

behavior w i l l of course be somewhere between this and the equilibrium

process.

This means a process in which there

Actual

Since non-equilibrium fractionation of LiF-BeF2-ThF4 melts

produces final liquids which are low in thorium, and since the concentrations of rare earths in the solutions are expected to be about

20 ppm at the time when fuel processing is economically mandatory, one might anticipate that a semi-zone refining step might w e l l produce

and transport liquids of low thorium concentration and containing a relatively high concentration of rare earths (the solubility of the lanthanide trifluorides in any of the melts one might encounter is

almost certainly to be at least 200 ppm at the low temperatures which would be present in this part of the feeder apparatus), of this concentration step could possibly be impaired seriously if the

rare earth trifluorides either formed intermediate compounds (such

compounds are formed only for the lanthanides of = 63) which interacted with the crystallizing phases or otherwise formed solid solutions with any'of the crystallizing phases. The structure of 2LiF.BeF2 and LiFeThF? are known and believed to be incapable of serving as solid

state hosts for the rare earth fluorides. The 3LiFeThF4 solid solution is an unknown factor in this consideration and could conceivably act as a solvent for lanthanide ions.

possibility that LiF92ThF4 might also serve as a solid state solvent

for lanthanide ions could be examined easily through a small scale laboratory program.

The efficiency

>

8

This possibility a$ well as the

--

29

1. Consultant, Department of Chemistry, New York University, University Heights, New York.

2. M. E. Whatley et al., Nuclear Applications, (in press).

3. J. H. Shaffer and D. M. Moulton, Reductive Extraction Processing of MSBR Fuels, in Reactor Chemistry Division Annual Report for Period Ending February 28, 1968, ORNL-4396.

4 . R. E. Thoma, H. Insley, H. A. Friedman, and C. F. Weaver, J. Phys. Chem. 64, 865 (1960).

5. J. E. Ricci, Guide to the Phase Diagrams of the Fluoride Systems, ORNL-2396, 1958.

6. G. D. Brunton, ORNL, Unpublished work, 1969.

7. C. F. Weaver, R. E. Thoma, H. Insley, and H. A. Friedman, Phase Equilibria in Molten Salt Breeder Reactor Fuels, I. The System LiF-EkF2-UF4-ThF4, ORNL-2896, December, 1960.

8.

9. G. D. Brunton, 21, 814 (1964).

J. H. Burns and E. K. Gordon, Acta Cryst. - 20, 135 (1966).

31

DISTRIBUTION

1. 2 . 3 . 4 . 5 . 6 . 7 .

9 . 10. 11. 12 . 1 3 . 14. 15. 16. 17 . 1 8 . 19 . 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49.

a.

R . K. Adam G . M. Adamson R . G. Affel J . L. Anderson R . F. Apple C. F. Baes J. M. Baker S. J. Ball C. E . Bamberger C. J. Barton H. F. Bauman S. E . Beall R . L. Beatty M. J. B e l l M. Bender C. E. Bettis E. S. B e t t i s D. S . Bi l l ing ton R. E. Blanco F. F. Blankenship J. 0. Blomeke R. Blumberg E. G . Bohlmann C. J. Borkowski G . E. Boyd J. Braunstein M. A. Bredig R. B. Briggs H. R. Bronstein G . D. Brunton D. A. Canonico S. Cantor D. W. Cardwell W. L. Carter G. I. Cathers J. E. Caton 0. B. Cavin J . M. Chandler F. H. Clark W. R. Cobb H. E. Cochran C. W. Collins E. L. Compere K. V. Cook W. H. Cook J. W . Cooke L. T. Corbin B. Cox J. L . Crowley

50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. 72 73. 74. 75 . 76 . 77. 78. 79. 80. 81. 82. 83. 84. 85. 86. 87. 88. 89. 90. 91. 92. 93. 94. 95. 96. 97. 98.

F. L . Culler D. R. Cuneo J. M. Dale D. G . Davis R. J. DeBakker J . H. &Van S. J. Di t to A. S. Dworkin I. T. Dudley W. P. Eatherly J. R. Engel E. P. Epler D. E. Ferguson L. M. F e r r i s A. P. Fraas J. K. Franzreb H. A. Friedman D. N. Fry J. H. Frye, Jr. W. K. Furlong C. H. Gabbard R. B. Gallaher R. E. Gehlbach J. H. Gibbons L. 0. Gi lpa t r ick W. R. G r i m e s A. G. Grindell R . W. Gunkel R . H. Guymon J. P. Hammond B. A. Hannaford P. H. Harley D. G . Harman W. 0. Harms C. S. Harrill P. N. Haubenreich G. M. Hebert R . E. H e l m s P. G . Herndon D. N . Hess J. R. Hightower M. R. H i l l H. W. Hofflnan D. K. Holmes P. P. Holz R. W. Horton A. Houtzeel T. L. Hudson W. R. Huntley

32

DISTRIBUTION

99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. 110. 111. 112. 113. 114. 115. 116. 117, 118. 119. 120. 121. 122. 123. 124. 125. 126. 127. 128. 129. 130. 131. 132. 133. 134. 135. 136. 137. 138. 139. 140.. 141. 142. 143. 144. 145. 146. 147.

H. Inouye W. H. Jordan P. R. Kasten R. J . K e d l M. T . Kelley M. J. Kelley C. R . Kennedy T. W. Kerl in H. T. Kerr J. J . Keyes D. V. Kiplinger S. S. K i r s l i s J . W. Koger R. B. Korsmeyer A. I. Krakoviak T. S. Kress J. W. Krewson C. E. Lamb J. A. Lane J. J. Lawrence M. S. Lin R. B. Lindauer A. P. Litman E . L. Long A. L. Lot t s M. I . Lundin R. N . Lyon R . L . Macklin H . G . MacPherson R . E . MacPherson J . C. Mailen D. L . Manning C. D. Martin W. R . Martin H. V. Mateer C. Matthews T . H . Mauney R. W . McClung H. E. McCoy D. L. McElroy C. K. McGlothlan C. J . McHargue H. A. McLain L . E. McNeese J. R. McWherter H. J. Metz A. S. Meyer R . L . Moore D. M . Moulton

148. 149. 150. 151. 152. 153. 154. 155. 156. 157. 158. 159. 160. 161. 162. 163. 164.

165-167 168. 169. 170. 171. 172. 173. 174. 175. 176. 177. 178. 179. 180. 181. 182. 183. 184. 185. 186. 187. 188. 189. 190. 191.

192-201. 202. 203. 204. 205. 206. 207.

T. R. Mueller H. H. Nichol J. P. Nichols E. L. Nicholson L. C. Oakes P. Pa t r i a r ca A. M. Perry T. W. P icke l H. B. Piper B. E . Prince G. L. Ragan J. L. Redford M . Richardson G . D. Robbins R. C. Robertson W. C. Robinson K. A. Romberger M. W. Rosenthal R. G. Ross H. C. Savage W. F. Schaffer C . E. Sch i l l i ng Dunlap Sco t t J. L. Sco t t H. E. Seagren C. E. Sessions J. H. Shaf fer W. H. Sides M. J. Skinner G . M. Slaughter A. N. Smith F. J. Smith G. P. Smith 0. L. Smith P. G. Smith I. Spiewak R. C . S t e f fy H. H . Stone R . A. Strehlow J . R. Tallackson E. H. Taylor W. T e r r y R. E. Thoma P. F. Thomason L. M . Toth D. B. Trauger W. E . Unger G . M. Watson J . S. Watson

33

DISTRIBUTION

208. 209. 210. 211. 212. 213. 214. 215. 216. 217. 218. 219. 220. 221. 222. 223.

224-225. 226-227 228-230.

231.

H. L. Watts C. F. Weaver B. H. Webster A. M. Weinberg J. R. Weir W. J. Werner K. W. West M. E. Whatley J. C. White R. P. Wichner L. V. Wilson Gale Young H. C. Young J. P. Young E. L . Youngblood F. C. Zapp Cent ra l Research Library Document Reference Section Laboratory Records Laboratory Records (LRD-RC)

EXTERNAL DISTRIBUTION

232. C. B. Deering, AEC-OSR 233. A. Giambusso, AEC-Washington

234-235. T. W. McIntosh, AE+Washington 236. H. M. Roth, AEC-OR0 237. M. Shaw, AEC-Washington 238. W. L . Smalley, AEC-OR0

239-253. Division of Technical Snfonnqtion Extension (DTIE)

Y