he batch and radiotracer technique was ap-
plied to monitor the sorption of traces of silver on
to PUF. An aqueous solution (5 cm
3
) of known
pH or acid concentration was taken in a glass
culture tube and silver radiotracer was added and
mixed thoroughly. A 1 cm
3
aliquot was with-
drawn to measure the initial activity (
A
0
). The
remaining solution was agitated with washed PUF
plugs (
29 mg) for 20 min on a wrist action
shaker. After phase separation, a 1 cm
3
aliquot
was again withdrawn and assayed radiometrically
(
A
F
) on a Tennelec gross-gamma counter
equipped with a 30 cm
3
well type NaI (Tl) crystal.
The sorbed concentration of silver onto PUF and
of distribution ratio (
K
d
) were computed using the
following equations [5].
%Sorption
A
0
A
F
A
0
100 (1)
K
d
A
0
A
F
A
F
V
:
W
(2)
The percent sorption and
K
d
can be correlated by
the following relationship:
%Sorption
100
K
d
K
d
(
V
:
W
)
(3)
where
V
is the volume of solution (cm
3
) equili-
brated with ‘
W
’ g PUF. All the experiments were
carried out at 23
9
2°C as specified otherwise, at
least in triplicate. The results were the average of
these independent measurements and precision in
most cases was
9
3%. The linear regression anal-
ysis was carried out for statistical treatment of the
data