A quasi-mechanistic non-electrostatic modelling approach to metal sorption on clay minerals

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Surface Complexation Modelling J. Lutzenkirchen (editor) © 2006 Elsevier Ltd. All rights reserved.

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A Quasi-Mechanistic Non-Electrostatic Modelling Approach to Metal Sorption

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M.H. Bradbury and B. Baeyens

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A Quasi-Mechanistic Non-Electrostatic Modelling Approach to Metal Sorption

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M.H. Bradbury and B. Baeyens

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A Quasi-Mechanistic Non-Electrostatic Modelling Approach to Metal Sorption

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M.H. Bradbury and B. Baeyens

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+

-1

Net H consumption (mmol kg )

A Quasi-Mechanistic Non-Electrostatic Modelling Approach to Metal Sorption

150

(a) 100 50 0 -50 -100 -150 2

3

4

5

6

7

8

9

10 11 12

pH 5

(b)

0.03 M

3

d

-1

log R Ni (l kg )

0.01 M 4

0.1 M 2

1 2

3

4

5

6

7

8

9 10 11 12 13

pH

-1

log [Ni sorbed] (mol kg )

-1

(c) -2

-3

-4

-5

-6

-9

-8

-7

-6

-5

-4

log Ni equilibrium conc. (mol l-1)

525

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M.H. Bradbury and B. Baeyens

100

Ni

Ni(II) %

80

Ni(OH)0

2+

2

60

40

20

NiOH

Ni(OH) -

+

3

0 7

8

9

10

pH

11

12

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A Quasi-Mechanistic Non-Electrostatic Modelling Approach to Metal Sorption

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100

6

(a)

(b)

0.014 M Na

60

0.1 M Na

4 3

1 M Na

d

40

20

4

2 1

0.1 M Na 0

5

-1

log R Am(III) (l kg )

% Cd(II) sorbed

80

5

6

7

0

8

2

3

4

5

6

7

pH 7

9

10

11 12

7

(c)

(d)

1 M Na 6

-1

-1

log R Sn(IV) (L kg )

6

log R Th(IV) (l kg )

8

pH

5

0.1 M Na

5

4

d

d

4 3 2 1 3

4

5

6

7

8

9

10

11

3

2

12

2

3

4

5

6

7

8

9

10

11

pH

pH 1000

6

(e)

(f) log R U(VI) (l kg )

-1

-1

log R Np(V) (l kg )

5 4 3

d

d

100

1

10 5

2

6

7

8

pH

9

10

11

0 2

3

4

5

6

7

pH

8

9

10

11

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A Quasi-Mechanistic Non-Electrostatic Modelling Approach to Metal Sorption

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M.H. Bradbury and B. Baeyens

15 10 5

-5 -10 -15 -20 -25 -35

-30

-25

-20

-15

-10

-5

OH

log

K

X

1 0

W1

K

x-1

-1

log

S

log K

x-1

0

-2 -3 -4 -5 -6 -12

-10

-8

log

-6

OH

K

x

-4

0

5

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M.H. Bradbury and B. Baeyens

5

6

log R Pu(IV) (l kg )

(b) 5

-1

4

3

4

3

d

d

-1

l o g R P b (II ) (l k g )

(a)

2

1

2

1 3

4

5

6

7

pH

8

9

10

11

3

4

5

6

7

pH

8

9

10

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A Quasi-Mechanistic Non-Electrostatic Modelling Approach to Metal Sorption

4.5

7

(b)

4

6

3.5

5

-1

log R (L kg )

-1

log R Ni (l kg )

(a)

4

d

d

3 2.5

3 2

2

1

1.5

0

5

6

7

pH

8

9

3

4

5

6

7

pH

8

9

10

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M.H. Bradbury and B. Baeyens

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