Distribution Coefficients—The distribution coeffi-

cients for the partition of cesium and rubidium be-

103

eee ony ay an ne

tween zirconium ferrocyanide and aqueous solutions

of ammonium nitrate and nitric acid are shown in
Figure 19.

Using nitrie acid, the values of the distribution coefficient decrease from 3143 at zero acid concentration to 1.8 with 9 M acid. The rubidium is not at all
strongly adsorbed, and the values of distribution coefficients decrease from 23.8 at zero acid concentration to 0.56 with 9 M acid. The differences between
the distribution coefficients for cesium and rubidium
for every acid concentration are large.

102

io!

Similarly, there is a very sharp drop in the dis-

Ceen a an rN meeps ear oe

NH4NO3z SOLUTIONS

HNO3 SOLUTIONS

-

Ka

tribution coefficients for cesium from 3143 at zero
NH,4NOz concentration to 123 with 2 M ammonium

nitrate, and then a gradual decrease to 17 for 9 M.
The distribution coefficients for rubidium decrease
from 23.8 at zero ammonium nitrate concentration to

°
io" =
f= CESIUM

The value of the distribution coefficient of 23.8 for
the partition of rubidium between water and zirconium ferrocyanide is lower by a factor of almost one

io!

0.95 at 8 M ammonium nitrate and show poor reproducibility.

hundred for other heavy metal ferrocyanides investi-

|
L

o

+ RUBIDIUM

[odo
i0 8 6

Fic. 17-—Distribution coefficients for partition of cesium

gated.

and rubidium between copper ferrocyanide and nitric acid or

Separation of Cesium and Rubidium from Columns
of Zirconium Ferrocyanide—The short ion exchange

ammonium nitrate.

0.6

NeiRES oidRE ee ae. arta

0.51r—

z
°
Ee 0.4;r—
<
a
ra
z

6 MNH4NO3
Rb

1 PRE that ee, AEPBA

YERe AN REayer RA mE re

an

org

tad

his
age
ves
ure
ite,

2
Zz 03
0.
Oo
ul

>

a 02
a
uJ

rd

8M NH4NO3

0.1

Cs

4
OQ

oO

|

2

°

|

4

l

6

|

8

oO
Oo

g
Lobo
4 2 0 2 4 6 8 10
MOLARITY

FM

gee ae AT RN eT

TT TTET

Zirconium Ferrocyanide

TT TTT

1o*

TT TTTTF

but there appears to be a little contamination with
ceslum.

POT TTT

oe Mae See A RAeR EECNR te IRS

23

oO
|

Io

|

{2

|

14

|

{§

VOLUME {milliliters}

Fic. 18.—Separation of rubidium and cesium using copper ferrocyanide

|

t8

Select target paragraph3