Adsorption of Copper on Particulates along a Salinity Gradient

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ADSORPTION OF COPPER ON PARTICULATESALONG A SALINITY GRADIENT

By

SULLEIMAN ADEBAYO ADEDIRAN. B.Sc .• M.Sc .. ~

A ThesisSubml~ted to the School of Graduate Studies

in Partial FulFi Iment of the Requirements, For the Degree

-Doctor of Philosophy

McMaster UniversityApri I. 1985 ©

..

ADSORPTION OF COPPER ALONG A SALINITY GRADIENT

I

DOCTOR OF PHILOSOPHY(1985)(Geology)

McMASTER UNIVERSITYHamilton. Ontario

TITLE:

AUTHOR:

SUPERVISOR:

NU~BER OF PAGES:

Adsorption of Copper on Particulatesalong a sal inity Gradient

Sulleiman Adebayo AdediranB.Sc .• M.Sc. (Univ. of IFe)

ProFessor James R. Kramer

xv. 175

i i

, To the memory of my Parents•

iii

A~STRACT

The scavenging or Cu w~s studIed along a sal inity

gradient using a rererence clay mineral (Si I ver Hi I I

I I lite. I Mt-!) and sed i ments ~rom La Have estuary (Nova

Scotia). Experiments were conducted in progressive

(Sal inograd) and batch mixing systems. The adsorption or Cu

in the ~al in~grad is oct signifi,cantly diF~erent From that

in the batch system.. The higher val~es in the Sal inograd

probably rerlect experimental artifacts resulting from the

inclusion or dialysis membrane to retain suspended

particles in each mixing tank or the Sal inograd.

The measured adsorptidn (distribution coerficient.

Kd ) or Cu in the laboratory experiments de~reased

drastically in the low. sal inity regime. This ~u~gests a

dilution phenomena or Cu along an estuarine prori le.;-.

Field measurements or particulate Cu and other trace metals

support th j s h~pothes i s.)

The distribution coerficient varies inversely with

sediment concentrations (100-1000 mg/L). The experimental

data fit the O'Connor & Conno J I y (1980) Power law runct ion:

at sal inities or 2.9-11.0 0/00.

where c • and B~ are empirical coerricients and m is the

sediment concentration. It appears however. that this

•fv

I n verse re 1at ions is strong I y dependent on sa lin i ty ( i.e.•

a and 8 are the sal inity parameters in the Power law runction).

The explanation to this inverse relationship can

be re 1ated part I y to "rad i oco I 10 i d" rormat ion wh i ch tends

to increase the metal concentration in the particulate.

phase. The errects or these colloids are more important at

the lower sol id concentrations than at the higher

concentration. An additional or possibly more important

contributor to the decrease in Kd as particle concentration

increases is inter-particle association. This particle-

particle interaction tends to block adsorption sites as

particle come closer. col I ide and aggregate at large

sediment concentration and higher ionic strength.

The adsorption or Cu prior to and arter chemical

extractions or the particulates. indicates that the organIc

phase is the most important "sink" ror Cu. The order or

importance or the d i rrerent phases in i I lite (I Mt-l) and

La Have sediments is:

Organic> Fe-Mn oxIde »» Clay mIneraI (I 1 1 ite)

v

ACKNOWLEDGEMENTS

I.am indebit\d to my research ~upervisor.

James R. Kramer. H\.s-support. interest and •

en~our~gemen~ ove~ the past Four years were invaluable

towards the 'completion of this thesis. I am appreciative

of'theguidance 'and interest shown by the members of my·- .-.

S..,oeT'v i sory Comm i t'!:ee: Drs. B.J. Bur ley. H:D. Grundy.

J.O Nriagu and D.R.' WOOds:'"

•Many others cont;ributeQ in one way or the other

towards th i s study. I thank these peep Ie:

Dr. S. Landsberger For introducing me to neutron

activation analysis.

Drs. D.E. Buck 1ey. R.E. Cranston.' M.A. Rashid.

G. Vi lks and Mr. K.R. Rober~son (BedFord Institute of

Oceanography. Nova Scotia) For their co-operation during,

my Field work.

Pierre Cote (Canada Centre For Inland Waters) For

al lowing me to use his BET equipment.

Mrs. J'i I I Gleed (A.A. ana I ys i s). Messers Ota

Mudroch (XRF analysis) and Jack Whorwood (Photography) For,

their technical assistance.

My co I leagues in the "JRK Team". Franco is Caron.

Steve Dav i es. Pau I a Takats. Laur i e Turner. Peter V i,l ks and

Moire Wadleigh provided me with an atmosphere conducive to

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••this academic upl iFtment, I am indebited to them and

particularly to Peter Vi lks who accompanied me to the Field

and was my I i Fa;uard in the ca I m waters of La Have r i ver-

estuary. Dr. Kurt PulFer (CIBA-GEIGY. Switzerland) was

very helpFul during the construction of the Sal inograd

whiles he was here as a Post doctoral Fel low.

owe-much to my Friends Francis Ajayi. 'Debo Akano

and Sam Aryee For being Friends at all times.

Financial support For this work came From the

University of IFe (Nigeria) and a grant From Energy Mines &

Resources (Canada).

Finally, I appreciate the constant encouragement.

prayers and understanding of my Fami Iy. without which this

dissertation would probably haVe remained uncompleted•

vii

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TABLE OF CONTENTS PAGE

\Abstract iv

Acknowledgements vi

List of' I I I ustrat ions xi 1

List of' Tables xvi

I. MET~L~ IN THE AQUATIC ENVIRONMENT

.2.

2.1

2.2

2.2.1

2.2.2

2.2.3

2.3

2.3.1

. 2.3.2

2.4

2.4. 1

2.4.2

2.4.2.1

CONTROLS AND MODELS OF TRACE METAL PATHWAYSIN THE AQUATIC SYSTEMS: A REVIE~

•Introduction

Estuarine Substrates

The Clay Minerals

Hy~rous oxides of' Iron and Manganese

Organ i c Matter

Copper in Estuarine Waters

Speciat{On of' Cu in estuarine systems

Behaviour of' Cu in estuaries

Adsorption: theories. models andand their appl ications

Development of' the Electric Double Layer

Other models and their appl ications

Surf'ace Complexation models

v Iii

5

5

5

6

8

1 1

16

16

20

22

24

24

,

TABLE OF CONTENTS (CONT'DJ

2.4.2.2 lon-Solvent Interaction model

2.4.2,3 Ion Exchange model

2.4.2.4 • Electrochemical model

2.4.2.5 Organic-Metal-Inorganic-substrateinteractions /

2.5 Simulatory Experiments

2.6 - Summary

3. DEFINITION AND SCOPE OF RESEARCH

4. MATERIALS AND METHODS

PAGE

29

30

" 30

3 I

34

36

39

43

4. 1

4.2

4.3

4.4

4.4.1

4.4.2

.. 4.4.3

4.4.3.1

Introduction

Laboratory Estuarin~Simulation:

Apparatus Des i gn ..-- .

Field Study Area and Sampl ing

Experimental and Analytical Procedures

Substrate Preparation and Characterization

Solution Composition

Adsorption Studies

Equil ibration Time

43

44

48

'50

50

55

55

56

4.4.3.2 pH Control

J4.4.3.3 Radiotracer Technique

4.4.3.4 Adsorption Experiments

ix

__~_m _

56

57

58

TABLE OF CONTENTS (CONT'D)

,

PAGE

4.4.3.4.1

4.4.3.4.2

4.4.3 ._4. 3

Adsorption onto Dialysis membraneand LEP container

"­Copper adsorpt i on on sed i ments

Data Analysis

58

59

6 I

4.5

5.

5. I

5.2

5.3

Extraction Technique

RESULTS

Par~iculate Characteris~ics

Adsorption of Cu onto Di~YSiS-and LPE container

EFFects of hydrodynamic5 on Cuadsorptio"n

membrane

62

65

65

67

70

5.4

. 5.5

5.6

5.7

5.7.1

5.7.2

InFluence of sediment concentration onadsorption

EFFect of the diFFerent components(oF sediments) on adsorption

Comparison of the adsorption behaviour ofIMt-1 and and La Have sediments

Metals in La Have estuary sediments

Total Metal in Particulate phase

Trace Metal Speciation

70

73

76

81

81

84

5.7.2.1 Copper

5. 7.2.2 Mang~nese

5.7.2.3 Iron

5.7.2.4 Zi8C

5.7.2.5 Lead

x

•~_,I

87

91

92

93

93

TABLE OF CONTENTS (CONT'D)

5.7.2.6 Cadmium

5.7.2.7 Cobalt

6. DISCUSSION: PATHWAYS OF METALS IN LA HAVER I VER-ESTUjlR.Y

6.1 Introduction

6.2 Sources of metals into La Have river-estuary

6.3 Factors inFluencing the adsorption ofCopper as sal inity changes

6.3. I InFluence of the type of mixing on adsorption

PAGE

94

95

96

96

96

100

100

6.3.2

6.3.3

6.3.4

6.3.5

6.4

7.

7.1'

7.2

EFFect of changes in sal inity onCu adsorption

Impo,tance of the d~erent phases ofsediment as "sinks" For Copper

f

The signiFicapee of the adsorbentconcentrat i o,n on meta.] uptake

Adso!ption model: Extrapolating FromLab~ratory studies to the Field

Environmental SigniFi~ance of the behaviourof Cu .along the salinity gradient

,SUMMARY AND CONCLUSIONS

Summary

Conclusions

REFERENCES

APPEND ICES,

xi

103

108

1 15

;(126

126

127

131

157

-LIST OF ILLUSTRATIONS

Fig. 2-1 The inFluence of organics on theadsorption of trace metals by clay minerals

PAGE

14

Fig. 2-2 The inorganic speciation of Cu in 19estuarine waters

Fig. 2-3 Theoretical calculation of thespeciationoF Cu along the sal inity gradient

Fig. 2-4 The progress and drawbacks inthe understanding of the electric double layer.sur~ace charge and adsorption

Fig. 2-5 Adsorption at the oxide-waterinterFace as proposed by the surFace complexationmodels

21

25

27

Fig. 2-6 The possible complexation reaction 33pathways between metals and organic ligands

)Fig. 2-7 The diFFerent possible modes of 35

interaction between organics. metals. clays andhydrousoxides

Fig. 4- I The Sa I i nograd: A laboratory 45analogue of one-dimensional mixing in estuary

F f g. 4-2 The Iocat i on of t~ study -area 49(LaHave river-estuary) and sampl ing stations along-€he estuarwroFi Ie

Fig. 4-3 X-ray peaks of ill i te (l Mt-l) and 53three sediments From La Have estuary

Fig; 4-4 Outine of the Tessier et al.(1979) 64sequential extraction scheme

Fig. 5-1 Percentage adsorption of Cu on 68SpectraPor 6 MWCO 1000 dialysis membrane and 125 mLNalgene LPE container as a Function of sal inity

x j i

LIST OF ILLUSTRATIONS(CONT'O) PAGE

Fig. 5-2 The eFFect of pre-treating 69dialysis membrqne with Cu so"lution beFore theadsorption of "b4Cu (50 ~g/L)

Fig. 5-3 The adsorption of Cuon three 71diFFerent concentrat ions of i I lite (I Mt- I) as aFunction of sal inity in the Sal inograd and theBatch systems

Fig. 5~4 The inFluence of sol id concentrations 75on the adsorption of Cu at diFFerent sal inities

Fig. 5-5 The eFFect of the removal of 77Fe-Mn oxide. organics and organics-Fe/M~ oxideFrom the surFace of IMt-1 i I I ite on the adsorption ofCu along a sal inity gradient

Fig.5-6 The eFFect of the removal of Fe-Mn 78oxide. organics and organics-Fe/Mn oxideFrom thesurFace of La Have estuary sediments on the adsorptionof Cu along a sal inity gradient

Fig. 5-7 Comparison of the adsorptivecapac it i es of I Mt-l i I lite (SH) and sed i ments FromLa Have estuary

80

Fig. 5-8 The concentration proFi Ie of 82metals in the bottom sediments of La Have estuary

Fig. 5-9 ProFi Ie of Cu in the bottom 85sediments in relation to the sal inity gradientand suspended particulate matter (SPM) inLa Have estuary

Fig. 5-10 The speciation of metals along 86the salt gradient of La Have estuary and IMt-1 i I lite

~

Fig. 5-11 The percentage of total metal in 88each of the Tessier et al. extraction Fraction ofLa Have sediments along the sal inity gradient

Fig. 5-12 The proport ions of the exchangeab I e," 89carbonate. Fe-Mn oxide and organics in the non-residualFractions of trace metals in La Have estuary sediments

x f f i

LIST OF ILLUSTRATIONS '(CONT'o) PAGE

Fig. 6-1sediments and insa lin i ty prof'i I e

The concentration of' Cu in bottomthe overlaying waters alongtheof' La Have estuary

107

Fig. 6-2 The correlation between the IIIadsorption of' Cu and the total Fe (FeZ03) andorganic matter contents of' La Have estuary sediments

xiv