New Understanding of Clay Minerals New Understanding of Clay - - PowerPoint PPT Presentation

New Understanding of Clay Minerals New Understanding of Clay Minerals

Sang-Mo Koh Geology and Geoinformation Division, KIGAM

• 2006. 11. 27

Clay & Clay Minerals Clay & Clay Minerals

Contents Contents

Introduction Definition of clay and clay minerals Classification of clay minerals Structure of clay minerals Properties of clay minerals Utilization of clay minerals New field of clay minerals Organo-clay : Modified clay Nano-composite clay

Introduction

Field of Clay Mineralogy Field of Clay Mineralogy

Clay Mineralogy

Mineralogy

Crystallography Quantitative chemistry

Geology

Soil science

Physical chemistry

All the materials with size less than 2μm in soils (ISSS)

ISSS: International Society of Soil Science

What is clay ? What is clay ?

Ceramics Definition

A very fine grained soil that is plastic when moist but hard when fired.

Civil engineering

Decomposed fine materials with the size less than 5μm in weathered rocks and soils

Geology

Sediments with the size less than 1/256mm (4μm)

Pedology Size terminology Size terminology

What is clay mineral ? What is clay mineral ?

Definition in Clay Mineralogy (Bailey, 1980)

Clay minerals belong to the family of phyllosilicates and contain continuous two-dimensional tetrahedral sheets of composition T2O5 (T=Si, Al, Be etc.) with tetrahedral linked by sharing three corners

• f each, and with the four corners pointing in any direction. The

tetrahedral sheets are linked in the unit structure to

• ctahedral sheets, or to groups of coordinating cations, or individual

cations

Classification of clay minerals Classification of clay minerals

Definition in Clay Mineralogy (Bailey, 1980)

Layer type Group (x=charge per formula unit) Subgroup Species Kaolin Kaolinite, dickite, halloysite, nacrite Serpentine Chrysotile, lizardite, amesite Pyrophyllite Pyrophyllite Talc Talc Montmorillonite (dioctaheral smectite) Montmorillonite, beidellite, nontronite Saponite (trioctahedral smectite) Saponite, hectorite, Dioctaheral vermiculite Dioctaheral vermiculite Trioctaheral vermiculite Trioctaheral vermiculite Dioctaheral mica Muscovite, illite, glauconite, paragonite Trioctaheral mica Phlogopite, biotite, lepidolite Dioctaheral brittle mica Margarite Trioctaheral brittle mica Clintonite, anandite Dioctaheral chlorite donbassite Di,trioctaheral chlorite Cookeite, sudoite Trioctaheral chlorite Chlinochlore, chamosite, nimite Sepiolite Sepiolite Palygorskite palygorskite Palygorskite~ sepiolite x=variable Chlorite x=variable Brittle mica x=2.0 Mica x=0.5-1.0 Vermiculite x=0.6-0.9 Smectite x=0.2-0.6 Pyrophyllite~ talc x=0 2:1 1:1 Kaolin~ serpentine x=0

Structure of clay minerals Structure of clay minerals

Definition in Clay Mineralogy (Bailey, 1980) Tetrahedron structure

Structure of clay minerals Structure of clay minerals

Definition in Clay Mineralogy (Bailey, 1980) Three ways of tetrahedral sheet

Structure of clay minerals Structure of clay minerals

Definition in Clay Mineralogy (Bailey, 1980) Octahedron structure

Structure of clay minerals Structure of clay minerals

Octahedral sheet

Six coordination number

Divalent cations (Mg2+) : Three of every

• ctahedral sites are
• ccupied

: Trioctahedral Trivalent cations (Al3+) : Two of every

• ctahedral sites are
• ccupied

: Dioctahedral

Trioctahedral & dioctahedral sheet

Structure of 1:1 type clay minerals Structure of 1:1 type clay minerals

1:1 layer structure consists of a unit made up of one octahedral &

• ne tetrahedral sheet, with the apical O2- ions of the tetrahedral

sheets being shared with the octahedral sheet. Kaolin and serpentine group

Structure of 2:1 type clay minerals Structure of 2:1 type clay minerals

Octahedral sheet

2:1 layer structure consists of two tetrahedral sheet with one bound to each side of an octahedral sheet. Smectite, micas, pyrophyllite, and vermiculite etc.

Equipment for research of clay minerals Equipment for research of clay minerals

X-ray Diffractometer Thermal Analyser FTIR SEM TEM EPM A

Qualitative and quantitative analysis of clay minerals Study on the crystal structure Study on the mineral chemistry Study for the utilization of clay minerals

Properties of clay minerals Properties of clay minerals

Permanent negative charge ( 2:1 clay minerals)

• By isomorphic substitution in octahedral and tetrahedral site

[ octahedral site: Al 3+ (Fe 3+)→Fe 2+, Ca 2+, Mg 2+ ] [ tertrahedral site: Si 4+ → Al 3+ , Fe 3+ ] pH dependent charge or edge charge (1:1 clay minerals)

• Broken, structural defect (terraces, kinks, holes)
• react with water molecules to form surface hydroxyl group

aluminol and silanol functional group

Properties of clay minerals Properties of clay minerals

Negative Charge : Cation Exchange Capacity (CEC) : High Adsorption Capacity of Heavy Metals & Cationic nuclides Mineral type CEC (cmol/kg) Kaolinite 3-15 Halloysite (2H2O) 5-10 Halloysite (4H2O) 40-50 Zeolite 100-300 Diocahedral vermiculite 10-150 Trioctahedral vermiculite 100-200 Chlorite 10-40 Biotite 10-40 Smectite 80-150

Properties of clay minerals Properties of clay minerals

High Surface Area : high adsorption capacity

Surface area(cm2/g) Mineral type BET EGME Montmorillonite 35 ~ 48 810 Kaolinite 5 ~ 9 48 Halloysite 76-173 Atapulgite 50 ~ 83 Illite 89 ~ 112 193 Talc 2.4 ~ 5.8 7 Vermiculite 350 Hectorite 461

EGME Ethylene Glycol Monoethyl Ether High Refractoriness : SK

Properties of clay minerals Properties of clay minerals

High Viscosity Mineral type Viscosity (cP) : 10% solution Bentonite 10-30 Pyrophyllite 1-1.5 Kaolin 1-1.2 Sericite 1-1.2 High Expansion & Swelling Colloidal property Hydrophyllic property : well dispersed in the water solution Very easily hydrated and dehydrated High plastic property : important property of ceramic materials

Classic Utilization Classic Utilization

Ceramics : pottery, sanitary ware, refractory brick, tile etc. : kaolin, pyrophyllite, illite(sericite) Plastic Plastic Materials Materials Refractory Refractory Materials Materials Flux Material Flux Material

Mixing, Mixing, Molding, Molding, Drying, Sintering Drying, Sintering

Classic Utilization Classic Utilization

Filler : paper, plastic and rubber (kaolinite, pyrophyllite) Cosmetics : kaolinite, smectite, illite, talc Glass fiber : pyrophyllite, dickite Civil engineering (water barrier & stablizer) : bentonite (smectite) Foundry : bentonite (smectite) Agricultural fertilizer : pyrophyllite, kaolinite etc. Environmental barrier : backfill material of waste disposal site : artificial barrier of nuclear disposal site

Classic Utilization Classic Utilization

Best Clay Minerals Best Clay Minerals ?

?

for Environmental Remediation or Treatment for Environmental Remediation or Treatment

Bentonite Bentonite

Industrial ore composed of smectite (mainly montmorillonite)

Montmorillonite

R+

0.33 (Al1.67Mg0.33)Si4O10(OH)2

Expandable interlayer Exchangeable cations in interlayer

high adsorption capacity

Pre-purification Post-purification

Waste water purification

• precipitation of phosphates
• sorption of heavy metals
• purification of sewage plants

: nitrogen and ammonium gases

Bentonite Bentonite

Liner of Waste Disposal Site ( Prevention of leachate)

Bentonite Bentonite

Nuclear Waste Disposal Site

Radionuclide transport barrier : adsorption of nuclides

New Field of Clay Minerals

Recent New Field of Clay Minerals ? Recent New Field of Clay Minerals ? Modification of Clay Minerals

Pillared Clay

Organoclay Organo-modified clay

Purified clay (Ca-type clay)

• H2O

Na+ Organic substances H2O

Ca

• Ca

• Na

Na

• Preparation of

Nano-composite

What is Organoclay ? What is Organoclay ? Modification of Clay Minerals

Pillared Clay Organic chemicals can be adsorbed on the clay surface and interlayer. Compound of clay mineral and organic chemicals It is manufactured by the reaction between clay and chemicals.

Organoclay Organoclay Modification of Clay Minerals

Commonly used clay mineral : smectite Expandable Interlayer & high charge

Organo-modified minerals

Organo-sericite Organo-zeolite Organo-montmorillonite Different mineral types Different surfactants (chemicals)

Characteristics of organo-modified minerals manufactured by different minerals and chemicals

Organo-modified mineral Organo-modified mineral

2 12 22 32 42

2 Theta

2000 4000 6000 8000

Intensity (counts / second)

S 10.05 (001) S 5.03(002) M M M M M M Mo 12.5(001) S : Sericite C : Clinoptilolite M : Mordenite Mo : Montmorillonite CT : Opal-CT C Mo (002) Mo (020) CT Mo (005) Mo (006) S S S S S S S S S S S C C C C C C C C C

Hyamine 1622R Benzyldimethyltetradecylammonium (BDTDA) Benzyltrimethylammonium (BTMA)

5 Å

Three minerals Three Chemicals

Organo-montmorillonite Organo-montmorillonite

Hyamine

N O O

N

N

BDTDA (Benzyldimethyltetradecylammonium) BTMA (Benzyltrimethylammonium) 50 100 150 200 250 300 350 400 450

Exchanging amount compared to CEC (%)

50 100 150 200 250 300

Actual exchanged amount compared to CEC (%)

12.5 22.9 103% 27.3 14.1 27.5 14.0 14.1 191% 213% 239%

2 2 4 6 8 4 6 8 2 4 6 8 10

Na-montmorillonite

10 10

27.9 19.19 15.94 29.51 16.02 30.68 16.27 14.9 HYAMINE

• MONTMORILLONITE

BDTDA

• MONTMORILLONITE

BTMA

• MONTMORILLONITE

199% 238% 262% 40% 60% 78% 89% 93% 96% 97% Non-treated 103% Non-treated 30.84 2 THETA 4000 8000 12000 16000 20000 INTENSITY (COUNTS / SECOND)

XRD pattern of Hyamine-. BDTDA, and BTMA-montmrorillonite with increasing chemicals : the interlayer(d001) is gradually expanded to 27.9, 30.8 and 14.9Å. Adsorption capacity of three chemicals into montmorillonite BDTDA and Hyamine show the strong interlayer expansion and the excellent adsorption into montmorillonite.

Adsorption behaviors Adsorption behaviors

BDTDA-MONT HYAMINE-MONT BTMA-MONT

mmol Surfactant / L Amount adsorbed ( cmol / kg ) BDTDA

• Zeolite

BDTDA

• Sericite

Hyamine

• Zeolite

Hyamine

• Sericite

BTMA

• Zeolite

BTMA

• Sericite

0.0 0.5 1.0 1.5 2.0 2.5

Equilibrium concentration (mmol / L)

5 10 15 20 25

Amount adsorbed (cmol / kg)

Adsorption isotherm curves of several organomodified minerals Of them, BDTDA and Hyamine-montmorillonite show the strong and stable adsorption into montmorillonite So, montmorillonite is the best mineral & BDTDA is the one of the best chemicals for the manufacturing the organo-minerals.

Organo-modified montmorillonite

Most economic chemicals BDTDA (160 US$ / 50g) HDTMA (286 US$ / 50g) CP (77 US$ / 500g)

To investigate the adsorption capacity and behavior of CP exchanged smectite

Organic chemicals Organic chemicals Modification of Clay Minerals

Organic cations : Quaternary ammonium cations II . 화 학 물

N am e A bbreviation S tructure M r (chloride salt) H ex adecyl- trim ethyl- am m onium H D T M A + 320.01 C etylpyri- dinium (H ex adecylp- ridinium ) C P + 358.01 B enzyldim et- hyltetradecyl

• am m onium

B D T D A + 368.05

CP is firstly studied in my research Journal of Clay Minerals (2005)

4 8 12 16 20

mmol CP / l

50 100 150 200 250 300

CP ( cmol / kg )

4 8 12 16 20

mmol CP / l

50 100 150 200 250 300

CP ( cmol / kg )

CP – Na smectite CP – Ca smectite Adsorption isotherm curves of CP-smectite. CP shows the excellent adsorption into smectite like HDTMA and BDTDA-smectite : L – type isotherm

Adsorption Behavior Adsorption Behavior

HDTMA - Ca smectite

2 4 6 8 10

2Theta (degree)

2000 4000 6000 8000

Intensity (counts/second) 20% 40% 60% 80% 100% 150% 200% 250% 300% 350% 400% Non-treated 15.02 16.29 15.25 21.42 22.46 22.46 31.64 20.06 37.09 19.66 38.38 19.75 38.54 19.70 12.93 19.57 20.06 13.06 12.78 38.88 39.58 20% 40% 60% Non-treated 80% 100% 150% 200% 250% 300% 350% 400% 19.79 19.93 13.20 40.12

2 4 6 8 10

2Theta (degree)

4000 8000 12000 16000

Intensity (counts / second)

HDTMA - Na smectite

39.06 19.79 19.79 12.76 13.40 12.74 15.54 16.94 20.82 23.11 29.52 20.11 12.51 38.14 12.85 38.38 12.95 19.97 39.40

♣ ♣ XRD patterns of HDTMA-smectite exchanged with different HDTMA

concentration to check the change of smectite interlayer.

♣ ♣ With increasing of HDTMA amount, the interlayer is expanded to39-40 Å. ♣ ♣ Excellent adsorption and sequential adsorption in the smectite interlayer

d(001) ⇒ d(002) ⇒ d(003).

.

Interlayer expansion of HDTMA-smectite Interlayer expansion of HDTMA-smectite

2 4 6 8 10

2 Theta ( degree )

4000 8000 12000 16000

Intensity ( counts / second )

Nontreated 20%(18.8%) 40%(39.2%) 60%(58.6%) 80%(79.9%) 100%(99.7%) 140%(138.3%) 189%(170.2%) 220%(183.9%) 260%(194.7%) 300%(198.3%) 340%(202.4%) 380%(216.5%) 420%(222.2%) 12.7 15.3 16.1 16.1 22.4 22.6 23.2 21.9 40.4 40.5 21 40.7 21 40.7 40.7 40.7 40.9 40.9 20.7 20.7 20.6 20.8 20.8

CP-Na smectite

2 4 6 8 10

2 Theta (degree)

2000 4000 6000 8000 Intensity (counts / second)

Nontreated 20%(18.8%) 40%(39.2%) 60%(58.6%) 80%(79.9%) 100%(99.7%) 140%(138.3%) 180%(170.2%) 220%(183.9%)

260%(194.7%)

300%(198.3%) 340%(202.4%) 380%(216.5%) 420%(222.2%) 15.02 16.08 15.40 21.12 22.18 22.21 20.82 40.30 20.58 39.76 39.76 39.09 40.67 39.58 40.67 40.15 20.29 20.75 20.29 20.67 20.28 20.48

CP - Ca smectite

Interlayer expansion of CP-smectite Interlayer expansion of CP-smectite

♣ ♣ XRD patterns of CP-smectite exchanged with different CP concentration. ♣ ♣ It shows the strong interlayer expansion and adsorption like HDTMA.

So CP can be used for the economic organosmectite.

What’s property ? What’s property ? Modification of Clay Minerals

Pillared Clay

Hydrophyllic surface is changed to organophyllic nature Hardness Viscosity Flocculation (dispersion behavior) Sorption capacity Structure (Interlayer expansion)

Smectite (Bentonite) Organo-smectite

2 4 6 8 10 12

pH

HDTMA- bentonite BDTDA- bentonite CP- bentonite

2 4 6 8 10 12

pH

Na-be. Ca-be. Non-treated

pH pH

♣ ♣ Volume expansion caused by bonding between interlayer of

montmorillonite and water molecules.

5 10 15 20 25 30

Swelling (ml/2g)

Na-be. Ca-be. Non-treated

5 10 15 20 25 30

Swelling (ml/2g)

HDTMA- bentonite BDTDA- bentonite CP- bentonite

Swelling Swelling

2 4 6 8 10 12 viscosity ( mPa · s ) HDTMA- bentonite BDTDA- bentonite CP- bentonite 2 4 6 8 10 12 Viscosity (mPa· s)

Na-be. Ca-be. Non-treated

Viscosity Viscosity

♣ ♣ Turbidity measurement ♣ ♣ Na-smectite : steady ♣ ♣ Ca-smectite : flocculatoin ♣ ♣ Organo-smectite : fast and strong flocculation

Time (Minutes)

400 600 800 1000 1200 1400 1600 1800

Turbidity (NTU)

L E G E N D Non - treated Na - bentonite Ca - bentonite 1 5 10 10 20 30 40 50 60

Time (min.)

200 400 600 800 1000 1200

Turbidity (NTU)

LEGEND

HDTMA BDTDA CP

Flocculation and dispersion behavior Flocculation and dispersion behavior

Intercalation model of large molecules exchanged smectite such as HDTMA-, BDTDA, and CP-smectite. 40 Å (10+15+15)

Adsorption Model Adsorption Model

It is explained by the total length of expanded interlayer Double layered paraffin structure

5 10 15 20 25 30 35 40 45

2Theta (degree)

400 800 1200 1600 2000

Intensity (counts / second)

2

No heating 90° C Heating 250° C Heating 400° C Heating 600° C Heating 890° C Heating

HDTMA - smectite

♣ ♣ HDTMA-smectite

⇒ 250 °C > : HDTMA begins to decompose. ⇒ 400 °C : HDTMA is completely decomposed. ⇒ 600 °C > : smectite structure begins to decompose. ⇒ 890 °C : complete decomposition of smectite structue

19.4 13.8 12.8 12.6

500 1000

Temp.(° C)

• 20

20 40 60 20 24 28 32

DTA uv TGA mg

HDTMA - smectite

10.34mg 34.4% 93.13° C 268.84° C 889.36° C 606.94° C 403.60° C

Thermal stability of HDTMA-smectite Thermal stability of HDTMA-smectite

♣ ♣ BDTDA-smectite

⇒ 250 °C > : BDTDA begin to decompose. ⇒ 400 °C : BDTDA is completely decomposed. ⇒ 550 °C > : smectite structure begins to decompose.

5 10 15 20 25 30 35 40 45

2Theta (degree)

400 800 1200 1600 2000

Intensity (counts / second)

2

No heating 90° C Heating 250° C Heating 400° C Heating 600° C Heating 890° C Heating

BDTDA - smectite

24.6 14.0 12.5 10.9

500 1000

Temp.(° C)

• 20

20 40 60 20 24 28 32

DTA uv TGA mg

11.154mg 35.59% 89.87° C 248.74° C 402.98° C

BDTDA - smectite

554.57° C

Thermal stability of BDTDA-smectite Thermal stability of BDTDA-smectite

Thermal stability of CP-smectite

♣ ♣ CP-smectite

⇒ 250 °C > : BDTDA decomposed ⇒ 430 °C : completely decomposed ⇒ 600 °C > : smectite structure decomposed

5 10 15 20 25 30 35 40 45

2Theta (degree)

400 800 1200 1600 2000

Intensity (counts / second)

2

No heating 90° C Heating 250° C Heating 400° C Heating 600° C Heating 890° C Heating

CP-smectite 19.4 14.0 12.7 10.9

500 1000

Temp.(° C)

• 20

20 40 60 16 20 24 28 32

DTA uv TGA mg

CP - smectite

10.78 mg 36% 434.5° C 90.65° C 262.3° C 609.73° C 896.13° C

Thermal stability of BDTDA-smectite Thermal stability of BDTDA-smectite Generally HDTMA Generally HDTMA-

• , BDTDA

, BDTDA-

• , and CP

, and CP-

• smectite

smectite, , their thermal decomposition begins at 250 their thermal decomposition begins at 250 º ºC C and ends at around 400 and ends at around 400 º ºC. C.

Utilization of organoclay Utilization of organoclay

• 1950 ~ : soil amendment, paint, paper, lubricant, grease, flocculant,

adsorbent, cosmetics, medicines etc.

• Recent (G. R. Alther, 1998) : Removal of organic contaminants

Mortland (1970)

• G. Alther (1998)

Removed pollutants

Lubricants M anufacturing process water Oil and grease Paper Degreasing operation Oil and grease Cosmetics Electroplating Heavy metals Paint M etal casting Dye penetrate Soil amendment Ground water and drinking water Oil and grease Heavy metals BTEX Pentachlorophenol Wood treating Creosote Pigment production Organic pigments Dry cleaning Perchloroethylene

Utilization of organoclay ? Utilization of organoclay ?

AC H50M H100M H200M BD50M BD100M BD200M BT50M BT100M BT200M Na-M ZEO H-ZEO BD-ZEO BT-ZEO SER H-SER BD-SER BT-SER

0.0 5.0 10.0 15.0 20.0 25.0 0.0 10.0 20.0 30.0 40.0

Amount sorbed (g / kg)

0.0 10.0 20.0 30.0 40.0

Phenol

Benzene Toluene

Hyamine- & BDTDA-Mont. Excellent adsorbents of Organic pollutants (BTEX)

This histogram shows sorption capacity of organic pollutants (phenol, benzene and toluene) by manufactured organo-modified minerals.

Less than 4~5% nanocomposite organoclay is mixed with major materials for the light and strong parts of cars and cameras. Ablation performance. Environmental stability, etc. Improvement of mechanical properties (strength and thermal stability). Flammability resistance.

Recent New Utilization : Nanocomposite organoclay Recent New Utilization : Nanocomposite organoclay

Thank you for your attention !