Speciation and role of iron phases in cement to fix heavy ...cement08.in2p3.fr/Presentation Workshop pour site web/Wednesday 15...Speciation and role of iron phases in cement to fix

2nd Mechanisms and modelling of waste/cement interactions international Workshop

Speciation and role of iron phases in cement to fix heavy metals

J. Rose1,2, A. Benard 2,3, A. Masion 1,2, P. Chaurand 1,2, I. Moulin 4, J-Y Bottero1,2

1: CEREGE UMR 6635 CNRS-Univ. Paul Cezanne, 13545 Aix en Provence, France2 : ARDEVIE, Europole Méditerranéen de l’Arbois, 13545 Aix en Provence, France

3: INERIS Domaine du Petit Arbois, BP 33, 13545 Aix en Provence, France4: LERM, 10, rue Mercoeur, 75011 Paris, France

October 12-16, 2008Le Croisic/France

[email protected] http://Se3d.cerege.fr

http://nano.cerege.fr

Fixation of heavy metals (HM) in cement (OPC)

Many OPC mineral phases can fix HM:

C-S-H : Pb, Zn, Eu…

AFm : Cr (III, VI),

Ettringite : almost all !!!

Other minor phases…. (LDH…)

Leaching of Portland cement (as an example)

Cement corrosion

Dissolution / precipitation pH modification

Altered zone

Non-Altered zone

Kamali, 2003

pH >12.5

pH<12.5

Adenot, 1992

CSH

MonosulfoAlCaGel

of S

i and

Al

CSH décalc.

CSH Low Ca/Si

Ettringite++

Hydrog.

Ca/SiEttringite

Portlandite

CSH

Ettringite

MonosulfoAlCa

Water(Without carbonate)

Dissolution fronts

Altered zone

hydrogarnet hydrogarnet

Can fix heavy metalsCan fix heavy metals

0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Ca normS

Nor

mal

ized

con

cen

trat

ion

distance from solid-water interface (µm)

Unaltered layerUnaltered layer

XGT-5000 µ-XRF (HORIBA). (Rh X-ray

source, 15-50 KV voltage, 100-10 µm spot size

What about long term evolution (no ettringite…)

Leaching of Portland cement (as an example (30 days…at 35°C in water)

0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Ca normS

Nor

mal

ized

con

cen

trat

ion


EttringiteEttringitefrontfront

Alte

red

Alte

red

lay e

rla

y er

0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Ca normS

Nor

mal

ized

con

cen

trat

ion


0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Ca normS

Nor

mal

ized

con

cen

trat

ion


Leaching of Portland cement (as an example)

What about long term evolution (no ettringite…)Iron ? Iron (III) is highly insoluble.

Unaltered layerUnaltered layerEttringiteEttringitefrontfront

Alte

red

Alte

red

lay e

rla

y er

FeFeXGT-5000 µ-XRF

(HORIBA). (Rh X-ray source, 15-50 KV voltage,

100-10 µm spot size

Iron (oxyhydr-)oxide in natural systems

Alteration (hydrolysis): very long term!!Formation of FeOOH/Fe2O3

Transport and fixation of numbers of species during

oxidation-precipitation

Fe(III)OOH

Fe(II)

Release of numbers of

species during reduction

Cycle dissolution-neoformation

Associated with redox front and biological

activity

Natural system: (in oxic zones, near neutral pH)

Adsorption and Adsorption and incorporation into the incorporation into the matrix (ferrihydrite) : matrix (ferrihydrite) : U, Cr, Co, Ni, Mn, As, Se, Pb, U…)

AdsorptionAdsorption

NutrientsNutrients PollutantsPollutants

FeOOH amorphousFeOOH amorphous= ferrihydrite= ferrihydrite FeOOH / FeFeOOH / Fe22OO33 crystallisedcrystallised

(Goethite, hematite(Goethite, hematite……))

Iron (oxy-hydr-)oxides for waste treatment

Highly reactive mineralsMany metals and metalloïds can be adsorbed or incorporated They are used as adsorbants (water treatment, physico-chemical processes)

Raw water

Coagulation-Floculation :

Coagulant: iron salt

sludge

Iron phases in cement?? µ-XRF profiles

Altered Altered surfacesurface

0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Ca normSFe

Nor

mal

ized

con

cen

trat

ion


0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Ca normSFePb

Nor

mal

ized

con

cen

trat

ion


After long term leaching : one of the only remaining phase?After long term leaching : one of the only remaining phase?

Iron in Portland cement

Anh

ydro

us p

hase

Cement hydration=

dissolution + precipitation

calcium silicates

C3S, C2S3 CaO.SiO22 CaO.SiO2

Calcium Aluminates

C3A3 CaO.Al2O3

calcium-ferric aluminate

C4AF2 CaO (Al2O3,Fe2O3)

CaSO4CaSO4

Hyd

rate

d ph

ases

C-S-HxCaO.SiO2.yH2O

C3(A,F)H6

3CaO.(Al2O3 ,Fe2O3).6H2O

Ca(OH)2AFm

AFt (ettringite)

“ferric” phase (‘hydrated phase: FeOOH)?)

MMööschner schner et al, et al, GCA, 2008GCA, 2008

Hydration of C4AF what do we know?

calcium ferroaluminates

C4AF?

AFm

+SO4 -SO4

C3AH6

Ettringite

calcium aluminates

C3AF

Al<=>Fe?AFm

C3AH6 + Fe phase??

EttringiteMMööschner schner et alet al

GCA 2008:GCA 2008:Not starting from C4AFNot starting from C4AF

Teoreanu et al. (1979), Fukuhara et al. (1981), Rogers and Aldrige (1977), and Brown (1987) :

amorphous FeOOH phase can existNo molecular scale investigation

Iron in other cements: slag,…

FeC2F/C4AFFeOFe3O4

Aim of the work

To determine the speciation of iron on synthetic system (C4AF…)

To determine the speciation of iron on OPC… (still ongoing research)

To determine the interaction with heavy metals on synthetic system

…. To determine the speciation on leached OPC…?

Molecular scale approach: determination of the Molecular scale approach: determination of the iron speciation in cement phasesiron speciation in cement phases

From cmFrom cm1cm

1 mm S

Cr

Mg

100 µm

mmmm µµmm

OFeFeAs

2 R(Å) 4 6

SiCa

Polarized light microscopePolarized light microscopeXRDXRD…… SEM-EDX

µ-XRF (fragile samples)

(synchrotron (small spot size,

sensitive))

XASXASMicroMicro--XASXAS

(synchrotron)(synchrotron)ÅÅ

Structure at the local scale : X-ray Absorption Spectroscopy

XANES = X-ray Absorption Near-Edge Spectroscopy : REDOX STATE

EXAFS = Extended X-ray Absorption Fine-Structure : ATOMIC ENVIRONMENT

Element K1S L1 2S L22p1/2H 13.6 (eV)….Ar 3205.9 326.3 250.6K 3608.4 378.6 297.3Ca 4038.5 438.4 349.7…Ti 4966 560.9 460.2V 5465 626.7 519.8Cr 5989 696 583.8Mn 6539 769.1 649.9Fe 7112 844.6 719.9

L 1,2,3K

M 1,2,3,4,566880000 77000000 77220000 77440000 77660000 77880000 88000000

1 s1 s

EE00

EECC

μWhite line

Atome centralCentral AtomPrépicPré-edge

Edge= XANES

EXAFSEXAFS

Backscatterer

Energie ( eV)

EXAFS

χ(k) =μ(k)− μ1(k)μ1(k) − μ0(k)

μ0(k)μ1(k)

a b

c d

e

χ(k) =μ(k) − μ1(k)μ1(k) − μ0 (k)

Transformée deFourier inverse

EXAFS curve = Fingerprint of

the atomic structure

XANES = fingerprintEXAFS = fingerprint

Reference spectra :

Redox state

Symmetry

7100 7120 7140 7160 7180Energy (eV)

FeOOH (ferrihydrite)

γ-FeOOH (Lepidocrocite)

C4AF

C2AF

Fe(II) CO3

Fe3O

4 Magnetite

αFe2O

3Hematite

QuickTime™ and aNone decompressor

are needed to see this picture.







































From 0 to From 0 to …… 66--10 10 ÅÅ(multiple scattering : high e mean free path)(multiple scattering : high e mean free path)

4 6 8 10 12

-1

-0.5

0

0.5

1

1.5

2

k*χ(

k)

k(Å-1)

C2F

C4AF

LepidocrociteFerrihydrite

Fe rich clay (smectite)

Nontronite (Fe-Si clay)

GœthiteAkaganeite

Hematite

Magnetite

Maghemite

Siderite

AFm

Ettringite

XANES = fingerprintEXAFS = fingerprint

Reference spectra :

Redox state

Nature, number And distance of neighboring atoms









































From 0 to From 0 to …… 44--5 5 ÅÅ(single scattering :(single scattering :low mean free path)low mean free path)

EXAFS

In a sample : Fe is in C4AF (40%) and Ettringite (60%)

4 6 8 10 12

kχ(k

)

K(Å -1 )

Ettringite

C4AF

Sample = 0.5 Ettringite + 0.5 C4AF

4 6 8 10 12-1.2

-0.6

0

0.6

kχ(k

)

K(Å -1 )

Ettringite

C4AF

Sample = 0.6 Ettringite + 0.4 C4AF

The same The same with XANESwith XANES

Local scale study

Procedure : – PCA, then linear combination… (XANES and EXAFS)– EXAFS modelling (XANES : still difficult on heterogeneous

sample)

With XAS : the fit does not indicate that the mineral exist: it reflects a similar atomic structure

XAS does not require long range order.

RESULTS : Hydration of C4AF in LW (without sulfate)

Hydration liquid/solid ratio of 0.5, 10, 60.

10 15 20 25 30 35 40 45 50

C4AF hydrated 48 H

C4AF Anhydrous

2 theta (°) (Co kα)

X-r

ay c

ount

s C3AH6C3AH6

Rose et al, Waste Management, 2006Rose et al, Waste Management, 2006

Complete hydration : C3AH6Complete hydration : C3AH6

Hydration of C4AF in LW (without sulfate)

Hydration liquid/solid ratio of 10

8 10 12 14 16 18 20 22

C4AF hydrated 24 HC4AF hydrated 48 HC4AF anhydrous


8.2 Å

7.7 Å Anhydrous C4AF7.5 ÅC3AH6

Where is Fe??Where is Fe??AFM =

transition phase

EXAFS results at the Fe K edge

Comparison with FeOOH, Fe-oxides; carbonates, AFm, Ettringite, C4AF, C2F

4 6 8 10 12

-1

-0.5

0

0.5

1

1.5

2

k*χ(

k)

k(Å-1)

C2F

C4AF

LepidocrociteFerrihydrite

Fe rich clay (smectite)

Nontronite (Fe-Si clay)

GœthiteAkaganeite

Hematite

Magnetite

Maghemite

Siderite

AFm

Ettringite

AFm AFm and and Ettringite Ettringite from from Moschner Moschner et al GCA, 2008et al GCA, 2008


4 6 8 10 12

-0.4

0

0.4

0.8

1.2k*χ(

k)

k(Å-1)

C4AF hydrated 24 h

C4AF hydrated 48 h

C4AF anhydrous

AFm

Ettringite

Goethite

Ferrihydrite

4 6 8 10 12

-0.4

0

0.4

0.8

1.2k*χ(

k)

k(Å-1)

C4AF hydrated 24 h

C4AF hydrated 48 h

Calculated curve

59 % C4AF15 % ferrihydrite19 % Goethite

C4AF anhydrous

AFm

Ettringite

Goethite

Ferrihydrite

4 6 8 10 12

-0.4

0

0.4

0.8

1.2k*χ(

k)

k(Å-1)

C4AF hydrated 24 h

C4AF hydrated 48 h

C4AF anhydrous

4 6 8 10 12

-0.4

0

0.4

0.8

1.2k*χ(

k)

k(Å-1)

C4AF hydrated 24 h

C4AF hydrated 48 h

4 6 8 10 12

-0.4

0

0.4

0.8

1.2k*χ(

k)

k(Å-1)

C4AF hydrated 24 h

C4AF hydrated 48 h

C4AF anhydrous

AFm

Ettringite

AFm AFm and and Ettringite Ettringite from from Moschner Moschner et al GCA, 2008et al GCA, 2008

?? Difficulty ?? Difficulty to fitto fit

±±1010--15%15%


EXAFS modelling

χ(k) = −NiS0

2

kRifi θ, k,R i( )e −2σi

2k2e−2Ri

λ(k) sin 2kR i + φ i (k) + 2δ c(k)( )i=1

N

∑









































amplitudeamplitude phasephase

RR

CaCa

OOR R FeFe--OO = 2 = 2 ÅÅR R Fe Fe -- --CaCa = 3.4 = 3.4 ÅÅN N FeFe--OO = 6= 6

N N Fe Fe -- --CaCa = 8= 8


EXAFS modelling

Fe Fe -- Fe distance : how can we go further?Fe distance : how can we go further?

-3

-2

-1

0

1

2

3

4 6 8 10 12 14

experimental C4AF (48H)

calculated

k3χ(

k)

k(Å -1 )

48 H

Structural approach

Fe-Fe =2.95-3.35Å

Fe-Fe > 3.70Å

Fe-Fe =2.87-2.90Å Fe-Fe =

3.45-3.60Å

Structural approach

Atomic pair Distance (Å) Number of Fe neighbours

Fe--Fe 3.01 2

Fe--Fe 3.28 2

Goethite(α-FeOOH)

Ferrihydrite(amorphous-

FeOOH)

Hemathite(α-Fe2O3)

C3AH6 FeFe--CaCa 3.513.51ÅÅ 66

AFm FeFe--CaCa 3.35 3.35 ÅÅ 66

Fe--Fe 3.46 4

Fe--Fe 3.01 4.5

Fe--Fe 3.43 3.9

Fe--Fe 2.90 1

Fe--Fe 2.97 3

Fe--Fe 3.36 3

Fe--Fe 3.70 6

48 H

Hydration of C4AF (in LW)

FeOOH FeOOH + + hydrogarnethydrogarnet

What about Portland cement??

24 H..C4AF + FeOOH

4 6 8 10 12

-0.4

0

0.4

0.8

1.2k*χ(

k)

k(Å-1)

hydrated portland cement

C4AF hydrated 48 h

AFm

Ettringite

Goethite

Ferrihydrite

Iron in hydrated Portland cement

4 6 8 10 12

-0.4

0

0.4

0.8

1.2k*χ(

k)

k(Å-1)


C4AF hydrated 48 h

Calculated curve

30 % C4AF12 % FeOOH44 % AFm

AFm

Ettringite

Goethite

Ferrihydrite

4 6 8 10 12

-0.4

0

0.4

0.8

1.2

k*χ(

k)

k(Å-1)


C4AF hydrated 48 h

Calculated curve

30 % C4AF12 % FeOOH44 % Ettringite

AFm

Ettringite

Goethite

Ferrihydrite


AFmAFmEttringiteEttringite????


4 6 8 10 12-0.8

-0.6

-0.4

-0.2

0

0.2

0.4k*χ(

k)

k(Å-1)


Calculated curve


surface of leached portland cement

Calculated curve


In OPC at the micro scale

500500µµmm

#1#1#2#2#3#3

#4#4

7100 7120 7140 7160 7180 7200Energy (eV)

#1

#2#3#4

7100 7120 7140 7160 7180Energy (eV)

FeOOH (ferrihydrite)

γ-FeOOH (Lepidocrocite)

C4AF

C2AF

Fe(II) CO3

Fe3O

4 Magnetite

αFe2O

3Hematite

µµ--XRF (Fe)XRF (Fe)Lucia (SLS)Lucia (SLS)((µµ--XANES + XANES + µµ--EXAFS)EXAFS)

Summary

Hydration of C4AF (-SO4) : FeOO + Fe in hydrogarnet (No Fe and AFm??)In presence of SO4 (CaSO4) : ettringite (Mochner et al, 2008)

In OPC : remaining C4AF (local scale) + FeOOH + AFm (??). More amorphous Fe at the surface.

What is the role of iron phases in heavy metal fixation

Stage 1: C4AF + Heavy metal interactions…

Stage 2 : on ‘real’ system…

C4AF hydrated in presence of metals

Fe and lead : isotherms: (L/S ratio (0.5 to 60); with LW, [Pb]initial from 10-3 to 8.10-3 mol/l)

“Everything”fixed by the solid

“Nothing” in solution

Reactivity between iron phases and metals (pure system)

Fe and lead : isotherms: (L/S ratio (0.5 to 60); with LW, [Pb]initial from 10-3 to 8.10-3 mol/l)

“Everything”fixed by the solid

“Nothing” in solution


0 1 2 3 4 5 6 7 8

FDR

R(Å)

EXAFS at the Pb L edge

H2O

3.3 �

3.9 �

≈3.9 �

Pb radial distribution function

R(Å)

OFe

EXAFS at the Pb LIII edge

(Pb+FeOOH)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

4 6 8 10 12

Experimental

Calculated

k3*χ

(k)

K(Å-1 )

((Bargar Bargar et al, 1998)et al, 1998)


Fe in presence of Cr

10-6

10-5

10-4

10-7 10-6 10-5

C4AF hydrated with Cr(VI)

C4AF hydrated with Cr(III)

[Cr]

s m

ol.g

-1

[Cr]e(mol.l-1)

eof t

he

[Cr(

III)

+li

me

wat

er]

solu

tion

EXAFS at the Cr K edge

Cr

Atomic pair R(�) σ(�) N ResidueCr--Cr/Fe 3.29 0.080 2.0 0.0375

Cr--Ca 3.48 0.080 3.6Cr--Cr/Fe 3.55 0.102 3.5

C3A(Cr)H6 (Cr)FeOH

C4AF in presence of Cr(VI)

8 10 12 14 16 18 20 22

C4AF hydrated 24 H

C4AF hydrated 48 H

Anhydrous C4AF

C4AF + Cr(VI) fe/Cr=0.15

0

1000

2000

3000

4000

5000

6000

X-r

ay c

ount

s


7.5 Å

8.2 Å

7.7 Å

9.6 Å

Anhydrous C4AF7.5 Å

C3AH6

C4AF in presence of Cr(VI)

Al-Ca Layer

Interlayer

AFm

AlCa Interlayer site

Al-Ca layer

Al-Ca Layer

Interlayer

-+++

+ ++

Cr(VI)O42-

5980 6000 6020 6040 6060 6080 6100

C4AF + Cr(VI)

Cr(VI) in solution (100%)

Energy (eV)

And in leached Portland cement?

0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Pb

Fe

0

0.5

1

1.5

2

2.5

0 2000 4000 6000 8000

Pb

Fe

Si

A

B

????????

Lead and C-S-H

~1 Si at 3,75Å de Pb~0,8 Ca at 3,58Å de Pb

Si

Ca

Pb

New peak at +85.6 ppm

Si

ExperimentalCalculated

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8

FDR

R(Å)

EXAFS at the Pb LIII edge

CSH structure

CSH hydrated in presence of Pb

29Si NMR

-95-90-85-80-75-70-65ppm

Q2''

Q1 Q2

Q1''Q1'

Rose et al, Rose et al, langmuirlangmuir, 2002, 2002

First EXAFS results (noisy)

4 6 8 10 12

k2χ(

k)

K(Å -1 )

Pb in hydrated Portlant cement

Pb in leached Portlant cement

4 6 8 10 12-0.4

-0.2

0

0.2

0.4

0.6

0.8

k2χ(

k)

K(Å -1 )


Pb in leached Portlant cementFirst fits with First fits with Fe in the Fe in the second second coordination coordination sphere sphere

Fe in secondFe in secondcoordinationcoordinationspheresphere

EXAFS results

0 1 2 3 4 5 6

FFT

R+Δ(R) (Å)


Pb in leached Portlant cement

More IronMore Iron No enoughNo enough……

Conclusion

Existence of FeOOH amorphous phase after cement hydrationIron phases formed after C4AF hydration strongly “incorporate” metals (Cr, Pb…)Metal and iron in cement: needs further investigation (µ-XRF at the micron scale in leached zones…)Implications: iron(III) phases may play a positive role for the long term fixation of metals and metalloids…but under oxic conditions (reductive dissolution of iron).

Acknowledgment

J-L Hazemann and O. Proux (ESRF, FAME beamline)V. Briois (LURE, D44 beamline and SOLEIL Samba)A-M Flank (SLS-Soleil, Lucia beamline)

Funding from the European Community through the INERWASTE Craft European program, and the YPREMA company.

4 00 µm

CaCa

SS

MgMg

500500µµmm

highhigh

lowlow

µ-XRF

XGT-5000 X-ray spectro-microscope (HORIBA). (Rh X-ray source, 15 KV voltage, 10 µm spot

Reactivity of Iron oxide

Highly reactive particles(U, Cr, Co, Ni, Mn, As,

Se, Pb, U…)

Selenate

lead

Uranium

0 1 2 3 4 5 6

Fonc

tion

de d

istri

butio

n ra

dial

e

R(Å)

U-O

U-OHU-Fe

0 1 2 3 4 5 6

Fonc

tion

de d

istri

butio

n ra

dial

e

R(Å)

Pb-O

Pb-Fe

0 1 2 3 4 5 6

Fonc

tion

de d

istri

butio

n ra

dial

e

R(Å)

Se-O

Se-Fe

Reactivity of iron oxide

Structural approach

AFm

Atomic pair Distance Number

Al/Fe-O 1.91Å 6

Fe--Ca 3.51Å 6

Al/Fe-O 1.90Å 6

Al/Fe--Ca 3.35Å 6

C3AH6

EXAFS

0

2

4

6

8

10

12

0 1 2 3 4 5 6 7 8

F(R

)

R (A)

Transformée de Fourier: Probabilité de présence des atomes voisins de l’élément X.

Central atom

1st coordination sphere

2nd coordination sphere

Nucleation and growth of FeOOH (in water) = Ferrihydrite??

(Bottero et al, 1994, Rose et al, 1997)

Fe24 (16Å)

FeCl3FeCl3

Fe(NO)3Fe(NO)3

EdgeEdge

Double cornerDouble corner

Modeling

Calculation:Translation into a chemical-transport model code (CHESS-HYTEC)

Translation of experimental data into thermodynamic data

For Pb retention sites (Nonat C-S-H model (Nonat et al, 01, Pointeau ,01)SiOH + Ca2+ + Pb2+ + 3H2O – 4H+ <==> SiOCaPb(OH)3 log K(25°C) = -33.4SiOH + SiOH + SiO2(aq) + Ca2+ + Pb2+ - H2O – 4H+ <==> SiOH-CaSiOPb-SiOH log K(25°C) = -23.3

Experimental(µ-XRF) Calculated

(CHESS-HYTEC)

BenardBenard, Rose et al., , Rose et al., in prepin prep

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Speciation and role of iron phases in cement to fix heavy ...cement08.in2p3.fr/Presentation Workshop pour site web/Wednesday 15...Speciation and role of iron phases in cement to fix