Malmö, ABM meeting May 2012 Mineralogical investigations of the alternative buffer material test...

Malmö, ABM meeting May 2012

Mineralogical investigations of the alternative buffer material test – II. Exchangeable cation population rearrangement

Dohrmann, R., Kaufhold, S., BGR/LBEGSiv Olsson, Clay TechnologyPatrik Sellin, SKB


Motivation and questions• Large differences of initial and final exchangeable cation population of 10 blocks reported during 2010 meeting

• Open questions: - confirm this trend for more blocks - vertical profiles- Ca2+ dominating in the top region?- influence of cement at the top - combination of all data sets available


BGR sampling


Available blocks Block Material/abbreviation NH4Cl-ethanol Cu-trien Cu-trien5xcalcite horizontal vertical

30 MX80 29 MX80 28 Ikosorb (IKO)27 Dep. CAN 26 Ibeco Seal (IBE) 25 Friedland (FRI) 24 Asha 505 23 Calcigel (CAL) 22 Callovo-Oxfordian 21 Febex 20 MX80 granulate19 MX80 granulate +quartz18 MX8017 Kunigel V1 (JNB) 16 Rokle (Rawra) 15 Dep. CAN 14 Asha 505 13 Rokle (Rawra) 12 Callovo-Oxfordian11 MX80 10 Ikosorb (IKO) 9 Friedland (FRI) 8 Febex 7 MX80 granulate +quartz6 Ibeco Seal (IBE) 5 Calcigel (CAL) 4 Kunigel V1 (JNB)3 MX80 granulate2 MX80 1 MX80

samplingCEC method


I. horizontal variation


values of JNB-17 can be averagedMethod Bentonite Position Na+ K+ Mg2+ Ca2+ sum/CEC CEC

(cm) from contact (meq/100 g)

NH4Cl-ethanol JNB-Ref reference 86 2 1 9

NH4Cl-ethanol JNB-17 1 41 2 9 47



Cu-trien5xcalcite JNB-Ref reference 91 0 1 6 1.06 62Cu-trien5xcalcite JNB-Ref reference 92 0 1 6 1.00 64Cu-trien5xcalcite JNB-17 3 43 3 9 44 1.00 63Cu-trien5xcalcite JNB-17 3 44 2 9 44 1.02 61Cu-trien5xcalcite JNB-17 5 44 2 10 43 1.00 61Cu-trien5xcalcite JNB-17 5 45 3 10 42 1.02 61

Cu-trien JNB-Ref reference 102 1 3 36 1.41 59Cu-trien JNB-Ref reference 100 1 2 28 1.30 60Cu-trien JNB-17 0.1 41 0 9 86 1.37 49Cu-trien JNB-17 0.1 40 1 9 83 1.31 48Cu-trien JNB-17 1 45 1 9 74 1.29 58Cu-trien JNB-17 1 47 2 9 65 1.23 57Cu-trien JNB-17 3 43 1 10 74 1.29 58Cu-trien JNB-17 3 45 1 10 70 1.27 56Cu-trien JNB-17 5 43 1 10 74 1.29 58Cu-trien JNB-17 5 45 1 10 70 1.25 56Cu-trien JNB-17 7 46 2 10 68 1.25 59Cu-trien JNB-17 7 46 1 10 68 1.25 57

methods 1-3 JNB-Ref 94 1 2 17 1.19 61methods 1-3 JNB-17 1-7 44 2 10 58 1.18 59methods 1 and 3 JNB-Ref 7 1.03methods 1 and 3 JNB-17 1-7 45 1.01

average

(% / CEC)

(% / sum of cations)

contact

xx xx

possibly clinoptilolite dissolution?


Typical lateral variation

0

20

40

60

80

100

0 1 2 3 4 5 6 7 8 9 10 11 12

cm

exch

ang

eab

le c

atio

ns

(%/C

EC

or

%/s

um

)

Na+ K+ Mg2+ Ca2+

typical lateral cation distribution after retrieval

refe

renc

e va

lues

c

on

tact

Ca2+

Na+


No horizontal variation found for non-contact samples.

This trend was confirmed for the other blocks.

-> avarge values of reacted blocks were calculated and

compared with initial composition


values of reference blocks• All values were measured, some were corrected:

• CEC%EC ‘MX80 granulate + quartz’ = MX80 x 0.7 according to a quartz content of 30 wt.%.

• Na+ (Ca2+) values of blocks 9 and 25 were corrected to give Na+=100‑K+‑Mg2+-Ca2+

• Ca2+ values of block 22 were corrected to give Ca2+=100‑Na+‑K+‑Mg2+.


values of reacted blocks

• Ca2+ values of blocks 9, 22, and 25 were corrected to give Ca2+=100‑Na+‑K+‑Mg2+.

• Ethanolic NH4Cl-EC values of such samples were recalculated using the measured reference CEC to avoid largely inflated Ca2+ percentages and accordingly diminished percentages for Na+, K+, and Mg2+.


Na+ K+ Mg2+ Ca2+ sum CEC Na+ K+ Mg2+ Ca2+ sum CECBlock Material/abbreviation (meq/100 g) (meq/100 g)

30 MX80 69 2 8 24 103 85 49 3 7 41 10029 MX80 69 2 8 24 103 85 41 2 13 44 10028 Ikosorb (IKO) 56 2 24 19 100 9027 Dep. CAN 27 2 27 46 102 84 25 2 10 63 10026 Ibeco Seal (IBE) 87 3 4 7 100 88 24 1 11 63 10025 Friedland (FRI) 69 8 22 2 101 23 37 6 11 46 100 2124 Asha 505 67 1 15 20 103 91 23 1 13 63 10023 Calcigel (CAL) 3 2 22 72 100 65 23 2 13 65 102 6422 Callovo-Oxfordian 24 11 29 35 100 12 44 8 26 22 100 1221 Febex 25 1 39 34 100 98 23 1 16 60 10020 MX80 granulate 69 2 8 24 103 8519 MX80 granulate +quartz 69 2 8 24 103 5918 MX80 69 2 8 24 103 8517 Kunigel V1 (JNB) 87 2 1 10 100 61 42 2 9 47 100 5716 Rokle (Rawra) 1 2 21 76 100 74 34 1 14 51 10015 Dep. CAN 27 2 27 46 102 84 36 2 17 50 104 7614 Asha 505 67 1 15 20 103 91 33 1 21 49 103 8313 Rokle (Rawra) 1 3 24 71 99 74 41 3 21 44 109 7112 Callovo-Oxfordian 24 11 29 35 100 1211 MX80 69 2 8 24 103 85 54 1 17 37 109 7610 Ikosorb (IKO) 56 2 24 19 100 90 45 2 18 36 100 879 Friedland (FRI) 69 8 22 2 101 23 59 9 19 13 100 218 Febex 27 3 37 33 100 101 42 3 23 34 102 957 MX80 granulate +quartz 69 2 8 24 103 596 Ibeco Seal (IBE) 90 4 6 8 109 88 40 4 12 50 106 805 Calcigel (CAL) 4 2 19 76 100 65 44 2 8 47 1004 Kunigel V1 (JNB) 87 2 1 10 100 613 MX80 granulate 69 2 8 24 103 852 MX80 69 2 8 24 103 85 60 2 10 28 1001 MX80 69 2 8 24 103 85

1-30

average (only of those blocks which were analysed after retrieval; exchangeable cations: n=21; CEC: n=12)

48 3 18 32 66 39 3 15 45 62

1-30 MIN 1 1 1 2 12 23 1 7 13 121-30 MAX 90 11 39 76 101 60 9 26 65 95

reference material

(%) (%)

retrieved samples 1-9 cm (averages)


-80% -60% -40% -20% 0% 20% 40% 60% 80%

exchangeable cation population (%)

MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)

MX80 granulate +quartz

Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+

0% 20% 40% 60% 80% 100%


MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+

0% 20% 40% 60% 80% 100%


MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+a b c

-80% -60% -40% -20% 0% 20% 40% 60% 80%


MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+

0% 20% 40% 60% 80% 100%


MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+

0% 20% 40% 60% 80% 100%


MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+a b c

initially after exp. differenceEC %


initially after exp. difference

-60 -40 -20 0 20 40 60

exchangeable cation population (meq/100 g)

MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+

0 20 40 60 80 100


MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+

0 20 40 60 80 100 120


MX80

MX80

MX80 granulate

Kunigel V1 (JNB)

Calcigel (CAL)

Ibeco Seal (IBE)


Febex

Friedland (FRI)

Ikosorb (IKO)

MX80

Callovo-Oxfordian

Rokle (Rawra)

Asha 505

Dep. CAN

Rokle (Rawra)

Kunigel V1 (JNB)

MX80


MX80 granulate

Febex

Callovo-Oxfordian

Calcigel (CAL)

Asha 505

Friedland (FRI)

Ibeco Seal (IBE)

Dep. CAN

Ikosorb (IKO)

MX80

MX80

Na+ K+ Mg2+ Ca2+

EC meq/100 g


chloride transport

Figures taken from ABM status report


lesson learned I• horizontal variation of ECs and Cl- was small • CEC was lowered (5 %)• Na+: 48% initially, 39 % after exp. (36->26)• Mg2+: 18% initially, 15 % after exp. (13->10)• Ca2+: 32% initially, 45 % after exp. (24->34)• K+: 3% initially, no changes (2)

(values in meq/100 g)• 8 non-examined Na+ blocks: 6MX80, IKO, JNB

plus COX


lesson learned II• Ca2+ gain pronounced in upper 7 blocks• Blocks 24-30:

- Na+: 63% initially, 33 % after exp.- Ca2+: 20% initially, 53 % after exp.

• The smallest absolute redistribution of all bentonites was found in MX80 at position 2 (14 meq/100 g). • For the same material also up to 46 meq/100 g were recorded at the other end of the test parcel.


lesson learned III• No correlation of the extent of the redistribution of the exchangeable cation population with the peak temperatures could be identified • The total amounts of redistributed cations do not correlate with the CEC (R²=0.01)


gaines and losses of individual blocks


influence of neighbouring blocks gains and losseswith the same prefix:CAL, FRI, IBE, Rokle;example: CAL

gains and losseswith opposite prefixes:Asha, Dep.CAN, Febexexample: Febex

Na+, K+, Ca2+, Mg2+ Na+, K+, Ca2+, Mg2+

neighboring upper blocksandwiched block A (at position x)neighboring lower block

neighboring upper blocksandwiched block A (at position y)neighboring lower block

gains and losseswith the same prefix:CAL, FRI, IBE, Rokle;example: CAL

gains and losseswith opposite prefixes:Asha, Dep.CAN, Febexexample: Febex

Na+, K+, Ca2+, Mg2+ Na+, K+, Ca2+, Mg2+

neighboring upper blocksandwiched block A (at position x)neighboring lower block

neighboring upper blocksandwiched block A (at position y)neighboring lower block

An+>>Bn+,Cn+An+ ≈ Bn+ ≈ Cn+

(not for ASHA)


lesson learned IV• The influence of neighbouring blocks on cation redistribution during the ABM experiment was low • Obviously not only the material composition of the adjacent blocks was important for the adsorption behaviour but the position within the test parcel


vertical exchangeable cation profile


0 20 40 60

meq/100 g

dis

tan

ce

fro

m c

on

tac

t (c

m)

Na+

K+

Mg2+

Ca2+

0 20 40 60 80

% / CEC

dis

tan

ce

fro

m c

on

tac

t (c

m)

Na+

K+

Mg2+

Ca2+

reference material

reference material

0 20 40 60

meq/100 g

dis

tan

ce

fro

m c

on

tac

t (c

m)

Na+

K+

Mg2+

Ca2+

0 20 40 60 80

% / CEC

dis

tan

ce

fro

m c

on

tac

t (c

m)

Na+

K+

Mg2+

Ca2+

reference material

reference material

% / CEC meq/100 g

CEC of IKO is approximately 15-20% larger than MX80


lesson learned V• In vertical exchangeable cation profiles of the two adjacent blocks MX80 (No. 11) and IKO (No. 10) all exchangeable cations show bi-modal concentration distributions with gaps of

2% / 5% / 7% for Mg2+ / Ca2+ / Na+

-> different selectivities?

• Mg2+ was transported from IKO into MX80 but not into FRI


influence of the cement plug on top of the parcel


0% 50% 100%

1.25

3.5

5.5

7.5

9.5

11.5

13.5

15.5

17.5

19.5

MX

80

blo

ck

29

& 3

0

Ca %K %Mg %Na %


• Vertical trend was confirmed (less samples)

• Horizontally no changes but ≈ 5-10 % less Ca2+ in the outer parts (closer to the rock)


lesson learned VI• The so-called top blocks (No. 29 and 30) showed the opposite behaviour than expected.

• Ca2+ and Mg2+ increased downwards from the outer part of block 30 to the lower part of block 29 while Na+ decreased. Mg2+ increased from 6 to 14 %.

• Horizontally no changes but ≈ 5-10 % less Ca2+ in the outer parts (closer to the rock), however MX80 contains soluble Ca-minerals which could have overprinted Ca2+.

• This vertical process is still unclear because overall Ca2+ was enriched in the upper parcel region, so what was the driving force (temperature ?)?


Ca2+ sources• Ca2+ increased while Na+ and Mg2+ decreased

• ÄSPÖ water: ≈ 2500 mg/L Na+ and Ca2+ each, ≈ 8500 mg/L Cl-, and ≈ 500 mg/L SO42

-; Mg2+, Br-, and K+ (all < 100 mg/L)

• Carbonates: high TIC in Dep.CAN, IBE but didn’t change in bulk blocks

• Sulfates: high total S in Dep.CAN, FRI but didn’t change largely in bulk blocks


Thank you

Malmö, ABM meeting May 2012 Mineralogical investigations of the alternative buffer material test...

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Transcript of Malmö, ABM meeting May 2012 Mineralogical investigations of the alternative buffer material test...