Ch i l ti th dChemical separation methods apimplications on detection

LTDE Sorption Dif(LTDE

Johan Byegård / Magnus GeosigmaGeosigma

li d l t lpplied on complex water samples, limits for -spectrometry

ffusion ExperimentE-SD)

Kronberg / Kersti NilssonAB / SKBAB / SKB

LTDE at ÄSPÖ HRLNASA3067 (z -410 m)

KA3065A03

LTDE-SD, experimentelltexperimentelltkonceptp

LTDE-SD händelserLTDE SD, händelser Uttag av 16 st 24 mm dia provkätestsektionentestsektionen

d = 10 mmn = max 8 st per snitt

20072007ärnor i matrisberget runt

Tracers injected in maTracers injected in maexperiment

T G T GTracer Group Tracer G

Na-22 B1 Nb-95 B S-35

A Tc-99 B

Cl-36 A Pd-102 BCl-36

A Pd-102 B

Co-57 B2 Cd-109 B Ni-63

B2 Ag-110m B

Se-75 ? Sn-113 B Sr-85

B1 Ba-133

B

Zr-95

B2

A non-sorbing tracer, B1 cation exchange, B2 mainly surf

ain sorption diffusion ain sorption diffusion

G T GGroup Tracer Group

B2 Cs-137 B1

B3 Gd-153 B2

B2 Hf-175 B2B2 Hf-175 B2

B2 Ra-226 B1

B2 Pa-233 B2

B2 U-236 B3

B1 Np-237 B3

face complexation, B3 electrochemical reduction dependent

Gammasectru

eV4 ke

V

56 k

eV3

keV

103

keV

37, 6

62 k

e

Sr-8

5, 5

14

Ba-

133,

3H

f-175

, 343

Gd-

153,

Cs-

1H

E t d t d >99%Expected to decrease >99%Expected to decrease 10-90%

um injected tracers

275

keV

Na-

22, 1

E t d t d <10%%

Expected to decrease <10%

Proposed separation meProposed separation me

• Addition of DTPA lower cAddition of DTPA, lower cconcentration of Ca, will fosome of the tracers

• Passing the solution throu(Dowex Wx8)( )

• Expected outcome:Tri and tetra valent catio– Tri- and tetra-valent catioto DTPA than to the sulfoexchanfer

– Mono- and divalent will foand will be adsorbed to th

ethod:ethod:

concentration than the naturalconcentration than the naturalorm negative complex with

ugh a cation exchanger

ons will be stronger complexedons will be stronger complexedonic acids of the cation

orm weak complex to the DTPA he cation exchanger

Result of the Cation Exchang

Log K (DTPA)

Result of the Cation Exchang

Na-22 ? <3

Sr-85 9.77

Cs-137 ? <3

Ba-133 8.87

Co-57 19.27

Cd-109 19.2

Ag-110m 8.61g

Gd-153 22.56

Hf 175 35 4Hf-175 35.4

ge/DTPA separation process

% in cation % in eluate

ge/DTPA separation process

exchanger

99.9 0.08

99.98 0.02

99.98 0.02

99.93 0.07

4 96

16 84

19 81

8 92

<7 >93<7 >93

Gamma spectrum

10000000

514

keV

eV

100000

1000000

Sr-8

5, 5

Ba-

133,

356

ke

10000

100000

s

1000

coun

ts

keV

100

Gd-

153,

103

, 343

keV

1

10

Hf-1

75,

1-200 0 200 400 60

Energy

m after separation

eV662

keV

Eluate from cation exchangerCation Exchanger

Na-

22, 1

274

ke

Cs-

137,

6

00 800 1000 1200 1400

y (kev)

Sorption of Gd-153 duriSorption of Gd 153 duri1.00E-03

1.00E-04

(g-1

)

1 00E 05

C/A

tot

1.00E-05

1.00E-060 50 10

Elapsed

ing the exeperimenting the exeperiment

Na-22Gd-153Gd-153, separation process

00 150 200

d time (h)

Sorption of Hf-175 duriSorption of Hf 175 duri1.00E-03

1.00E-04

(g-1

)

1 00E-05

C/A

tot

1.00E-05

1.00E-060 50 1000 50 100

Elapsed t

ng the experimentng the experiment

Na-22Hf-175Hf-175, separation process

0 150 2000 150 200

time (h) Lets look closer on this

-spectrum Hf-1 spectrum Hf 1

10000

1000cond

s

1000

3200

0 se

100

unts

per

3co

u

10336 338 340 342

-en en

175 343 4 keV175, 343.4 keV

Non-processed sample(sum)Sorbed in cation echangerSorbed in cation echanger

Eluate from cationexchangerg

2 344 346 348 350

nergy (keV)nergy (keV)

-spectrum Hf spectrum Hf

180

200

140

160

180

econ

ds

Eluate from cationexchanger

100

120

3200

0 se

60

80

unts

per

3

20

40cou

0336 338 340 342

-en en

f-175, 343.4 keVf 175, 343.4 keV

2 344 346 348 350

nergy (keV)nergy (keV)

-spectrum Hf- spectrum Hf

10000co

nds

3200

0 se

Detection limit reported: 2.5 Bq-> 1440 net pulses

unts

per

-> 1440 net pulses

cou

1000336 338 340 342

-e

-175, 343.4 keV175, 343.4 keV

q

Measured non-processedsmaple + reported detectionlimit contsM d dMesured non-prcessedsample

2 344 346 348 350

energy (keV)gy ( )

-spectrum Hf spectrum Hf

8000

9000

6000

7000

8000

econ

ds

4000

5000

6000

3200

0 se

2000

3000

4000

unts

per

Detection limit reported: 2.5 Bq -> 1440 net pulses

1000

2000co

0336 338 340 342

-e

f-175, 343.4 keVf 175, 343.4 keV

Measured non-processedsmaple + reported detectionlimit contsM d d

q

Mesured non-prcessedsample

2 344 346 348 350

energy (keV)gy ( )

Summary and Conclusi

• A chemical separation meto detect and measure trato detect and measure trameasurable

• Detection limits?

ons

ethod has made it possoble acers atherwise notacers atherwise not