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 Contents Contents Introduction Definition of clay and clay minerals Classification of clay minerals
Sang-Mo Koh Geology and Geoinformation Division, KIGAM
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
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 belongs to the family of phyllosilicates and contain continuous two-demensional tetrahedral sheets of composition T2O5 (T=Si, Al, Be etc.) with tetrahedral linked by sharing three corners
tetrahedral sheets are linked in the unit structure to
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
: Trioctahedral Trivalent cations (Al3+) : Two of every
: 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 &
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
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
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, pyrophyllie, 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 barrrier of nuclear disposal site
Classic Utilization Classic Utilization
for Environmental Remediation or Treatment for Environmental Remediation or Treatment
Bentonite Bentonite
Industrial mineral composed of smectite (mainly montmorillonite)
Montmorillonite
R+
0.33 (Al1.67Mg0.33)Si4O10(OH)2
Expandable interlayer Exchangeable cations in interlayer
Pre-purification Post-purification
Waste water purification (high adsorption capacity)
: 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 ? New Field of Clay Minerals ? Modification of Clay Minerals
Pillared Clay
Organoclay Organo-modified clay
Purified clay (Ca-type clay)
+ + + + + + +Na+ Organic substances H2O
Ca
OH OHNa
OH OH OH OH OH OHNano-composite
What is Organoclay ? What is Organoclay ? Modification of Clay Minerals
Pillared Clay Organic chemicals are adsorbed on the clay surface. Compound of clay mineral and organic chemicals
Organoclay Organoclay Modification of Clay Minerals
Commonly used clay mineral : smectite Expandable Interlayer & high charge
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 Benzyltrimethylammonium (BTMA) 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
BDTDA
BTMA
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)
Adsorption behaviors Adsorption behaviors
BDTDA-MONT HYAMINE-MONT BTMA-MONT
mmol Surfactant / L Amount adsorbed ( cmol / kg ) BDTDA
BDTDA
Hyamine
Hyamine
BTMA
BTMA
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)
Montmorillonite is the best mineral for manufacturing the organo-minerals BDTDA is the one of the best chemicals for ~
Most economic chemicals (BDTDA) HDTMA CP
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
B D T D A + 368.05
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 isotherms of BDTDA- and HDTMA-smectite
are so similar to CP-smectite : L – type isotherm ♣ ♣ Adsorption behaviors same as the behavior of interlayer expansion ♣ ♣ Same adsorption regardless of interlayer cations of smectite
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
♣ ♣ 400% CEC equiv. amount exchanged : d(001) 39-40 Å expanded ♣ ♣ 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
♣ ♣ 400% CEC equiv. amount exchanged : d(001) 40 Å expanded ♣ ♣ BDTDA-smectite : d(001) 40 Å expanded (Koh and Dixon, 2002)
Interlayer expansion of CP-smectite Interlayer expansion of CP-smectite
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
♣ ♣ Generally Na+, Li+, K+, Ca2+, Mg2+ decreased
: Na+ highest surface potential
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 double layered paraffin structure of organic cations such as HDTMA, BDTDA, and CP (Koh, 2005) 40 Å (10+15+15)
Adsorption Model Adsorption Model
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 decomposed ⇒ 400 °C : HDTMA completely decomposed ⇒ 600 °C > : smectite structure decomposed ⇒ 890 °C : completely structural decomposition
19.4 13.8 12.8 12.6
500 1000
Temp.(° C)
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 decomposed ⇒ 400 °C : BDTDA completely decomposed ⇒ 550 °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
BDTDA - smectite
24.6 14.0 12.5 10.9
500 1000
Temp.(° C)
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
♣ ♣ CP-smectite
⇒ 250 °C > : CP 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 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 CP-smectite Thermal stability of CP-smectite
Utilization of organoclay Utilization of organoclay
adsorbent, cosmetics, medicines etc.
Mortland (1970)
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
BDTDA-Mont. Excellent adsorbents of Organic pollutants (BTEX)
Less than 4~5 vol % addition
alumino-silicate layers Ablation performance. Environmental stability, etc. Improvement of mechanical (modulus, strength, thermal expansion coefficient) properties. Enhanced barrier, flammability resistance.
Recent New Utilization : Nanocomposite organoclay Recent New Utilization : Nanocomposite organoclay
Clay-polymer nanocomposite clay : light and strong parts of cars and cameras