eichrom

Application Note: 1001

Tritium Columns

Expertise in Sample Preparation

Introduction: Eichrom's Tritium Column is designed to replace distillation for most routine
tritium analyses of aqueous samples. Methods using the Tritium Columns have been developed
to shorten the preparation time and decrease waste generation for a variety of sample matrices.
The Approach: The Tritium Column works by removing potential interferences in the LSC
spectrum, just as distillation does. It is not intended to be an enrichment procedure, and as such,it should be used only in situations where the required detection limit can be achieved by thedirect counting of a 5-10 mL aliquot of the sample (plus cocktail) processed through the tritiumcolumn.
Shown in Figure 1 are the three components in
the Tritium Column. Table 1 below explains
the target contaminates and capacity each of thecomponents in the column. The Diphonix®
Resin removes cations in exchange forhydrogen ions and its theoretical capacity is 0.8
mEq per column. The anion resin is standard
chloride form analytical grade 1X8 resin. It
exchanges anions in the sample for chlorideions. (It is recommended that the sample pH be>1.) The polymethacrylate component removes
organically bound tritium and carbon-14.
Table 2 shows the average spike recoveries fora variety of sample matrix types passed through Figure 1: Composition of Tritium Column
the tritium column.

Diphonix® Resin

Anion Resin
Prefilter Resin

Table 2
Spike Recovery Results using Tritium Column

Table 1
Component

TargetCapacity

Diphonix® Resin

Cations

0.8 mEq

Anion Exchange
Resin

Anions

0.8 mEq

Polymethacrylate
Resin

OrganicMolecules

50 mg

Sample TypeVolume3H Spike% Recovery

Distilled water

15 mL

97.2 Bq

96.4% (n=4)

Distilled water

25 mL

20.2 Bq

87.6% (n=4)

Distilled water

25 mL

19.5 Bq

94.9% (n=7)

Ground water

25 mL

17.1 Bq

91.2% (n=5)

Sea water

25 mL

4.0 Bq90.0% (n=6)

Urine

25 mL

85.1 Bq

91.1% (n=4)

The column successfully removes potential radioactive interferences. In a study performed at
Eichrom, a mixture of radioisotopes (60Co, 137Cs, 233U, 90Sr/90Y, 210Pb, 230Th, total activity 16.9Bq) was spiked into eight tritium-spiked solutions (distilled and sea water samples). In every
case, after passing the sample through the Tritium Column, the number of counts in the region
above the tritium window was not different than the number of counts in the same region of an
un-spiked sample. (See Table 3 on the next page)

08/27/2010

Application Note: 1001

Sample Type

Table 3Results of contamination study by Eichrom
3
H Spike (Bq) Contaminant spiked (Bq)
VolumeDistilled Water

25 mL

19.5

16.9

<MDA (N=2)

Distilled Water

25 mL

20.2

16.9

<MDA (N=2)

Sea water

25 mL

4.0

16.9

<MDA (N=4)

In another experiment, Daniel Cahill ofCarolina Power & Light measured theactivity of fission and activation products in
PWR and BWR reactor coolant samples
before and after passing through Eichrom'sTritium Column. Table 4 summarizes thebefore column activity of each sample. Afterthe column, no measurable activity wasdetected in the BWR sample and only a tracelevel of activity of 60Co with > 50% counting
error was detected in the PWR sample.
Because the amount of 60Co measured was solow and the error so high, and because theBWR sample contained more than 10 times
the 60Co before the column and none after
the column, it is assumed that the trace
amount measured in the PWR sample is anartifact due to the background of the gammacounter.

Contaminant found (Bq)

Table 4Carolina Power & Light Samples
Isotope
Cr-51
Mn-54
Co-58
Fe-59
Co-60
Sn-113
Nb-95
Zr-95
I-131
Cs-134
Cs-137
La-140Ce-144PWR Sample
BWR Sample
2,900
1,900
518
5,590
4,740
4,960
109
--392
5,990
230
--4,220116
2,210--14,200--1,1200--1,320----1,550--203
D. Cahill, Carolina Power & Light, New Hill NC

See our newsletter archive for additional data on the performance of Eichrom's Tritium Column.
The studies reported here, and elsewhere on our website, conducted in Eichrom and customer
laboratories, demonstrate that the Tritium Column performs equivalently to the traditional
distillation technique. We encourage you to try using the Tritium Column as a substitute for
distillation of your aqueous tritium samples.

eichrom
Eichrom Technologies LLC
1955 University Lane
Lisle, Illinois
60532 USA
Phone: (630) 963-0320
Fax:(630) 963-1928
Email: info@eichrom.com

08/27/2010

www.eichrom.com
Eichrom Europe Laboratories
Campus de Ker Lann
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