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Table 27. Sources and rates Sf
production of tritium in a
1000-m~e MSBP
Soharce
Production rate
MBq/s ci/a
Ternary fission 13 31
6Li (*,a) 3H 518 1210
%i (n 9 na> 3H 501 1170
1 9 ~ ~ ~ , 1 7 ~ ) 3 ~ 4 9
Total 1036 2420
“From ~ef. 77.
through hot metals will permit a Parge fraction of the ’82 to penetrate
the primary heat exchanger to enter the secondary coolant. This phenome-
non and its consequences are described briefly in Sect. 3.3.3.2,
Fission products with soluble stable compounds. Rubidium, cesium,
strontium, barium, yttrium, the lanthanides, and zirconium all form quire
stable fluorides that are relatively soluble in molten fluoride mixtures
such as MSBR and DMSR fuels. Isotopes of these elements that have no
noble-gas precursors, as expected, appeared almost entirely in the circu-
lating fuel s€ the MSRE.19,2Q,22*72 Very small quantities appeared at ~r
near the surface of exposed graphite spec5mens; most of this deposition
evidently resulted from fission recoil. Isotopes such as 89Sr and 14’Ba,
whose volatile precursors have appreciable half-lives and which were par-
tially stripped from the reactor, were found in samples of the cover gas
and within specimens of moderator graphite as well as in the fuel of the
MSRE. Along with behavior of other isotopes, Fig. 14 shows the profiles
observed for 1 3 . p ~ and ~ 14o~a in graphite specimens through diffusion of
their respective (137xe, 3.9 min; 140xe, 16 s> precursors.
Bromine and iodine would be expected to appear in the fuel as soluble
Br- and I-, particularly in the ease where the fuel contains an apgre-
ciable concentration of UP^.
NQ analyses for ~ rwere - performed during