92 Nuclear Forensic Analysis
Both of these procedures have been a focus of some industrial development, but they
a
re
n
ot
c
onsidered
m
ainstream
a
nd
w
ill
n
ot
b
e
d
iscussed
f
urther
he
re.
H
owever,
s
ee
R
ef. [8].
Other
me
thods
f
or
s
eparating
T
h
f
rom
t
he
r
are
e
arths
i
nvolve
t
he
s
elective
d
isso-
lution
o
f
T
h
i
n
e
ither
s
odium
ca
rbonate
o
r
a
mmonium
o
xalate.
I
n
b
oth
ca
ses,
t
he
l
an-
thanides
are efciently precipitated, whereas the soluble Th complexes, Na
6
Th(CO
3
)
5
a
nd
(
NH
4
)
4
Th(C
2
O
4
)
4
, remain in solution. After ltration, the complexes can be
d
estroyed by the addition of sulfuric or hydrochloric acid.
The
g
oal
o
f
m
ost
o
f
t
he
p
rocedures
d
iscussed
i
s
t
he
c
oncentration
o
f
T
h
i
nto
a
n
i
ntermediate
f
raction,
w
ith
t
he
r
emoval
o
f
p
hosphate,
s
ulfate,
a
nd