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Transcript of Nano Materials for Wwt
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Sabna V
P100017CE
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CONTENTS
y CURRENT SCENARIO
y NANOMATERIALS FOR WASTEWATER TREATMENT
NANOSENSORS FOR THE DETECTION
ADSORPTION OF POLLUTANTS
MAGNETIC SEPERATION
NANOFILTRATION FOR DESALINATION
PHOTOCATALYTIC DEGRADATION BY OXIDATION REDUCTION
DISINFECTION
y SUMMARY & CONCLUSIONS
y REFERENCES
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CURRENT SCENARIO
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World Stability
Energy (biofuels for energy) Water
Source depletion Increased water Demand
Over useContamination
Population growth
Intensive agriculture
Urbanization
Industrial growth
Environment requirements
Alternate Source Additional supply
Waste water reclamation and reuse
Seawater desalination
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Conventional methods of treatment
Chemically, energetically intensive
Infrastructure & capital engineering expertise
Residuals (sludge, brines, toxic waste)
Efficiency decreases due to accumulation
Focused on large systems
Reuse of waste water
Not suitable for most of the world
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Nanotechnology can play many roles
Sensing ability
No intensive use of chemicals Transformation of the pollutant
Removal of low-concentration contaminants
No production of toxic byproducts
More efficient energy utilization Reclamation and re-use of wastewater
Desalination of sea water
Not capital intensive
Large surface areas than bulk particles Possibility for functionalization with various chemical groups
Increased affinity, capacity, and selectivity for heavy metals and other contaminants
Enhanced reactivity, surface area and sequestration characteristics
Size and shape-dependent optical, electronic and catalytic properties
Selected nanomaterials water purification
Nora, Savageand Mamadou S. Diallo, Nanomaterials and water purification:Opportunities and challenges, Journal of Nanoparticle Research (2005) 7: 331342
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Pollution Detection and Sensing
Inexpensive, sensitive, flexible, and portable devices for chemical and
biological agents
Detection of chemical markers and to amplify the signal
Ag nanoparticle membrane array
CNT for electrochemical sensors
Antibiotics coated Magnetic nanoparticles specific to bacteria
X. Chen, Y. Dong, L. Fan, D. Yang, Anal. Chim. Acta 582 (2007)281.
W. Xu, J. Zhang, L. Zhang, X. Hu, X. Cao, J. Nanosci. Nanotechnol. 9 (2009) 4812.
Surface-enhanced Raman scatteringSurface plasmon resonance
Fluorescence
Electrochemistry
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Nano adsorption
Weak and reversible binding of molecules or particles to a surface Activated carbon, silica gel, and alumina
Nano adsorbents: separation media to remove inorganic and organic pollutants
Two key properties : 1. Larger SSA than bulk particles
2. Possibility for functionalization
Auffan 2007, Banfield and Navrotsky 2003; El-Sayed 2001
Larger surface area Greater sorption capacities Smaller sorbent volumes and
Less waste for disposal
Particle size decreases
More exposed unsaturated
surface atoms and
closer functional groups
Greater reactivity
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Carbonaceous nanomaterials
Nanoporous Activated Carbon Fibers (ACFs)
Carbon Nanotubes
Nanoporous Activated Carbon Fibers (ACFs)
Average pore-size : 1.16 nmSurface areas : 171 to 483 m2/g
Removed : Benzene, Toluene,
p-xylene, ethylbenzene
Higher organic sorption equilibrium constants than GAC
Mangun C.L., Z.R Yue, J. Economy, S. Maloney, P. Kemme & D. Cropek, 2001. Adsorption of organic
contaminants from water using tailored ACFs Carbon. Chem. Mater. 13, 23562360.
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Adsorption properties of CNTs
Chemically inert surfaces for physical adsorption
High SSA than AC
More well-defined & uniform atomic structure
Well-defined adsorption sites available
Highly porous & hollow structure
Light mass density
Possibility for functionalisation
Strong interaction b/w functional groups &
Pollutant
Xnemei Ren, Changhun Chen, Masaaki Nagatsu, Xiangke Wang, 2010, Carbon Nnaotubes as adsorbents in
environmenmtal pollution mamnagement: A review, CHEMICAL Enginnering Journel.
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Precipitation
Electrostatic attraction
Physical adsorption depends on surface area, open-ended & defect sites
Chemical interaction b/w metal ions and surface functional groups - Major
Pb(II) adsorption on acidified MWCNTs
Physical adsorption: 24.7%
Chemical interaction : 75.3%
Li Y.-H., J. Ding, Z.K. Luan, Z.C. Di, Y.F. Zhu, CL Xu, D.H. Wu & B.Q. Wei, 2003. Competitive adsorption of Pb2+, Cu2+ and Cd2+
ions from aqueous solutions by multiwalled carbon nanotubes. Carbon 41(14), 27872792.
MetalAdsorption on CNTs
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Sorption of Pb(II), Cu(II) and Cd(II) onto MWCNTs
97.08 mg/g for Pb(II)
24.49 mg/g for Cu(II)
10.86 mg/g for Cd(II)
Metalion sorption on MWCNTs were 34 times larger than PAC and GAC
CeO2-CNTs with 189 m2/g : effective sorbents for As(V).
CeO2-CNTs with Ca(II) and Mg(II): As(V) (from 10 to 82 mg/g).
Room temperature
pH 5.0
Metal ion eq. conc. : 10 mg/L
Yan-Hui Li, Jun Ding, Zhaokun Luan, Zechao Dia, Yuefeng Zhu, CailuXu, Dehai Wu and Bingqing Wei, Competitive adsorption of Pb2+,
Cu2+ and Cd2+ ions from aqueous solutions by multiwalled carbon nanotubes , Carbon Volume 41, Issue 14, 2003, Pages 2787-2792
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Jiangnan Zhang, Zheng-Hong Huang, Ruitao Lv, Quan-Hong Yang, and Feiyu Kang, 2009, Effect of Growing CNTs onto
Bamboo Charcoals on Adsorption of Copper Ions in Aqueous Solution, Langmuir, 25 (1), 269-274
Effect of Growing CNTs onto
Bamboo Charcoals
onAdsorption of Copper Ions
CBC700 lower than CBC800 & CBC900.
small quantity of CNTs growth at 700 C.
100 CBC800 16.34 mg/g twice of BC
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Jiangnan Zhang, Zheng-Hong Huang, Ruitao Lv, Quan-Hong Yang, and Feiyu Kang, 2009, Effect of Growing CNTs ontoBamboo Charcoals on Adsorption of Copper Ions in Aqueous Solution, Langmuir, 25 (1), 269-274
Precipitation of Cu(OH)2 at pH > 6Oxidation is favorable to ionization and ion exchange
20CBC800 : 13.12 mg/g at Cu conc. Of 17.50mg/L
20CBCO800 : 17.20 mg/g for oxidised CNT
Application of CNT for organic molecule removal
DCB maximum sorption capacity of 30.8 mg/g
MWCNTs adsorbed volatile organic compounds than carbon black
Alginate vesicles caged MWCNTs dyes (acridine orange, ethidium bromide, eosin
bluish and orange G).
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Influence of initial concentration
Influence of pH
Adsorption properties of Chitosan nanoparticles for Pb2+
Influence of size
Influence of amount
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Other nanoparticles for metal adsorption
Ofakaganeite [b-FeO(OH)]: As(V)
Nanocrystalline akaganeite : Cr(VI)
PO43- functionalized nanochitosan (40100 nm): Pb(II): 398 mg/g.
Nanoparticles for the removal of organic molecules
Incorporation of sodium dodecyl sulfate (SDS) into Mg - Al layered double hydroxides
(LDHs) hybrid inorganicorganic nanosorbents
Fullerenes and amphiphilic polyurethane nanoparticles: PAHs, naphthalene
Qi & Su (2004), Peng et al.(2005) Deliyanni et al. (2003) , Lazaridis et al. (2005)
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Zeolites
Effective sorbents and ion-exchange media for metal ions.
Na6Al6Si10O3212H2O zeolites high density of Na ion exchange sites.
Functionalized nanoporous ceramic oxides with very large surface
areas (1000 m2/g) and high density of sorption sites increase their
selectivity toward target pollutants.
Remove Cr(III), Ni(II), Zn(II), Cu(II) and Cd(II) from metal electroplating
and acid mine wastewaters
Moreno et al., Alvarez Ayuso et al. (2003)
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Adsorption by TiO2
Surface OH provides the ability to bind metal cations Solution pH influences the surface active site distribution
+vely charged (Ti-OH1/2+) surface when solution pH < pzc on TiO2 surface
-vely charged (Ti-OH1/2-) surface when solution pH > pzc on TiO2 surface
Exhaustion : contaminant release from the adsorbent back into solution
Morterra1988
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Karen E. Engates & Heather J. Shipley, 2010, Adsorption of Pb, Cd, Cu, Zn, and Ni to titanium dioxide nanoparticles: effect of particle size,
solid concentration, and exhaustion, Environ Sci Pollut Res
Adsorption of Pb, Cd, Cu, Zn, and Ni to titanium dioxide nanoparticles
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Negative adsorption : Release of
previously adsorbed metal
Nanoparticles exhausted in 3rd cycle but
bulk particles in 2nd due to increased
surface area
Release of Ni & Cd occurred because of
the occupation of open sites by Pb dueto its strong affinity for TiO2
At pH= 8, adsorption increased
due to pH> pzc
pH= 6 Nano 1st
Bulk 1st
Pb 96 % 32 %
Ni 6 % Exhaustion
Cd 14 % Exhaustion
Karen E. Engates & Heather J. Shipley, 2010, Adsorption of Pb, Cd, Cu, Zn, and Ni to titanium dioxide nanoparticles: effect of particle size,
solid concentration, and exhaustion, Environ Sci Pollut Res
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Cleaning Water with Nanorust,
Magnetic Separation
High magnetic gradient separation (HGMS) to remove compounds
Magnetite (Fe3O4), maghemite (g-Fe2O3) and jacobsite (MnFe2O4) nanoparticles
To remove heavy metals like Cr(VI), As etc. from wastewater
Magnetic nano iron functionalized CNTs for removal of aromatic compounds and
other organic pollutants
Not affected by parameters such as pH, salinity and dissolved organic matter
Coating Fe3O4 magnetic nanoparticles with humic acid can
Greatly enhance the stability of dispersed nanoparticles by preventing their aggregation;
Maintain the saturation magnetization by avoiding their oxidation; and
Enlarged adsorption capacity due to carboxylic acid and phenolic hydroxyl functional groups
Simply recovered from water with magnetic separations at very low magnetic field
Michael Berger. Copyright 2008 Nanowerk LLC, August 19, 2008
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As Removal using magnetic nanoparticles
As in groundwater is a severe in Southeast Asia
As is present in groundwater in the forms of AsO33- and AsO43-
Resemblance with HPO32- and PO4
3- ions: dominant source of their toxicity
AsO33- and AsO4
3- block ATP to ADP conversions by replacing PO43- groups
Magnetite nanocrystals (Fe3O4)
15 g nano Fe2O3 = 1.4 kg bulk Fe2O3 for g 500 g/l As from 50 l of water.
Cafer T. Yavuz J. T. Mayo, Carmen Suchecki, Jennifer Wang , Adam Z. Ellsworth, Helen DCouto, Elizabeth Quevedo, Arjun Prakash, Laura
Gonzalez, Christina Nguyen, Christopher Kelty, Vicki L. Colvin, 2010, Pollution magnet: nano-magnetite for arsenic removal from drinkingwater, Environ Geochem Health.
12 nm
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(a) AsIII at pH 3 and (b) AsV at pH 7 Reaction condition: 10mg/L
AsIII or AsV adsorbed on 0.2 g/ L adsorbents in 0.01M NaNO3
.
Adsorption behavior of As III & As V on bimetal oxides magnetic nanomaterials
Shengxiao Zhang, Hongyun Niu, Yuqi Lai,Xiaoli Zhao, Yali Shi, 2010, Arsenate and arsenite adsorption on coprecipitatedbimetal oxide magnetic nanomaterials: MnFe2O4 and CoFe2O4, Chemical Engineering Journel, 158, 599-607
MnFe2O 4=138 m2/g
Fe3O4 =102 m2/g
CoFe2O4 =101 m2/g
Adsorption on
MnFe2O 4 %
CoFe2O4 were
twice that of Fe2
O3
M-OH group
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Photo catalytic degradation
Catalysts : promotes chemical reaction of other materials withoutbecoming permanently involved in the reaction
Large surface areas and size and shape dependent optical,electronic and catalytic properties : catalysts and redox action
Nano TiO2 and ZVI
Degrade organic pollutants and
Remove salts and heavy metals
by Dispersed homogeneously in solution
Deposited on to membrane structures
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nZVI, 100 to 200 nm in dia, 33.5 m2/g consist of ZVI (Fe0).
larger surface areas and reactivity than bulk Fe
0
particles Fe(H2O)6
3+ + 3BH4 + 3H2O Fe0 + 3B(OH)3 + 10.5H2
Reduce chlorinated alkanes , alkenes, benzenes (PCB), pesticides, organic dyes, nitro aromatics
Reduce redox active metal ions such as Cr(VI) to less toxic Cr(III) precipitating Cr (III) hydroxides or
Cr Fe hydroxide
Reduce inorganic anions (e.g., nitrates).
Dechlorination of trichloroethene
C2HCl3 + 4Fe0 + 5H+ C2H6 + 4Fe
2+ + 3Cl-
Fe reactivity decrease due to precipitation of M-OH &M-CO3
2- onto Fe surface
Low reactiveZVI form hazardous byproducts.
RNIP : 50/50 wt% mixture of iron and magnetite (Fe3O4).
Core of the particles: elemental iron (-Fe)
Outer shell : Fe3O4 surrounds Fe
Zero Valent Iron
Wang 1997
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SEM images of the annealed (600 C) TiO2 thin films containing (a) Au, (b) Ag, and
(c) Cu nanoparticles. (d) SEM image of the pure annealed TiO2 thin film at 600 C.
Photoenhanced Degradation of Methylene Blue by TiO2- metal nanocomposites
Parvaneh Sangpour, Fatemeh Hashemi, and Alireza Z. Moshfegh, Photoenhanced Degradation of Methylene Blue on
Cosputtered M:TiO2 (M ) Au, Ag, Cu) Nanocomposite Systems: A Comparative Study
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3D AFM images (1 1 m2) of the annealed (600 C) TiO2
thin films containing (a) Au, (b) Ag, and (c) Cu nanoparticles.
(d) AFM image of the pure annealed TiO2 thin film at 600 C.
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Parvaneh Sangpour, Fatemeh Hashemi, and Alireza Z. Moshfegh, Photoenhanced Degradation of Methylene Blue on
Cosputtered M:TiO2 (M ) Au, Ag, Cu) Nanocomposite Systems: A Comparative Study
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Photo catalytic Activity
The variation of normalized C/C0 of MB concentration as a function of UV irradiation time (a)
without any catalyst nanoparticles. (b) TiO2 thin films containing Au, Ag, and Cu nanoparticles
annealed at 600 C.
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Degradation of phenol by nanomaterial TiO2
Degradation of phenol by nanomaterial TiO2 in wastewater , Chemical Engineering Journal,Volume 119, Issue 1, 1 June 2006, Pages 55-59
H+ or H is scavenged by
oxygen to form HO2 radicals,which finally convert to OH
radicals
Complete mineralization of pollutants to CO2, water and mineral acids
H may be produced through three routes:H2O + h
+ OH- + H+
OH + aromatic ring, C-H bond break up, OH replaces H
UV (472 kJ/mol) break O-H bond in H2O or phenol or C-H bond in phenol
Fenitrothion (an agricultural organophosphorous pollutant) by immobilised nTiO2
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y Strong oxidants (e.g., free chlorine, chloramines and ozone) are used as disinfectantsfor pathogens (e.g., bacteria and viruses)
Impairment of cellular function by destruction of major constituents (cell wall)
Interference with the pathogen cellular metabolic processes
Inhibition of pathogen growth by blockage of the synthesis of key cellular
constituents (e.g., DNA, coenzymes and cell wall proteins)
y Formation of DBPs because of strong chemical oxidants used in water treatment.
Trihalomethanes , Haloacetic acids & Aldehydes
y Nanomaterials provide chlorine-free biocides.
y functionalized nano surfaces mimic the structure and functionality of the
receptors of target protein residues.
y Can be designed with arrays of sites to trap all waterborne viral pathogens via
binding to host receptors.
Disinfection
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Silver Nanoparticles
Potential antimicrobial agent.
Medical applications : Ag based dressings, Ag coated nanogels, nanolotions
nAg by reducing AgNO3 with ascorbic acid
Effective against Escherichia coli.
Cellulose acetate (CA) fibers with embedded nAg
biocides against Gram-positive and Gram-negative bacteria
including Staphylococcus aureus, Escherichia coli, Klebsiella
pneumoniaeand Pseudomonas aeruginosa.
Adhesion to cell surface and cell membrane degradation by formation of pits.
Formation of Reactive Oxygen Species (ROS) by reaction with thiol groups in
cell protein.
Sondi & Salopek-Sondi (2004)
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Photoreversible antimicrobial properties of nAg
nAg deposited on a TiO2 semiconductor support consisted of Ag2O
Upon UV-A irradiation, e- in the VB of TiO2 move to CB, and then to nAg,
reducing Ag+ to Ag
Ag+ affect DNA replication and thus adenosine 5-triphosphate production
Activity decreases with time, but can be regained by irradiation with visible light
Photoinactivation depends on
incident light flux and wavelength,
absorption length through water,
geometry, reactor hydrodynamics,
contact efficiency of species in water on the photocatalysts
the inactivation kinetics
(Small2009, 5, 341344; George Xiu Song Zhao)
TiO2 doped with N (TiON), or N & Pd can be activated with visible light inactivate
viruses and pathogens with much lower energy
MgO nanoparticles against Grampositive and Gram-negative bacteria (Escherichia
coli and Bacillus megaterium) and bacterial spores (Bacillus subtillus).
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y Peptides:
Formation of nanochannels in cells and osmoticcollapse.
y
Chitosan: +vely charged Chitosan reacts with vely charged
cell membrane.
Penetration of cell wall and nucleus and bindingwith DNA.
useful in acidic pH only.
Coagulant/flocculant in water treatment systems. Low toxicity towards higher mammals and humans.
y ZnO:
Photocatalysis and formation of H2O2
Penetration and degradation of cell membrane.
y
Fullerenes: ROS production.
Exact mechanism still under debate.
y CNTs:
Physical interaction or oxidative stress whichcompromises cell membrane integrity.
Qilin Li, Shaily Mahendra, Delina Y. Lyon, Lena Brunet,
Michael V. Liga, Dong Li and Pedro J.J. Alvarez, Antimicrobial nanomaterials forwater disinfection and microbial control: Potential applications and implications
y MWNTs form uniform nanoporous, cylindricalmembrane walls.
y Mechanical stability,
y ability to maintain constant pressure,
y high thermal stability and
y absence of defects.
y packing of MWNTs in radial directions with
respect to macrotube gives good cross flow,minimum blockage due to organic and
inorganic pollutants.
y E. coli bacteria > StaphylococcusAureus >
Poliovirus Sabin 1 (25 30 nm) all can be
filtered completely.
y Repeated cleaning possible by ultrasonication
and autoclaving (@121oC; 30 min.)
y Can be operated at temperatures of 4000C
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peptides, chitosan,
carboxyfullerene, CNT,
ZnO, nAg
TiO2, ZnO and fullerol
Chitosan
DNA damage
interruption of energy
transduction (e.g. nAg and
aqueous fullerene
nanoparticles (nC60))
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Nanofiltration Microfiltration, ultrafiltration, nanofiltration and Reverse Osmosis (RO).
cations, natural organic matter, biological contaminants, organic pollutants, nitrates
and arsenic from groundwater and surface water.y Nanomaterial membranes have more resistance to fouling, selectivity, functionality
and permeability.
zeolite filtration membranes and nanocatalysts and magnetic nanoparticles
impregenated filters
doping nAl2O
3with Fe, Mn & La: increased selectivity &permeate flux through UF
deposition of poly(styrene sulfonate)/poly(allylamine hydrochloride) onto porous
alumina in NF: high water flux, high retention of divalent cations [Ca(II), Mg(II)]
and Cl-)/SO42-) selectivity ratios up to 80
TiO2 filter with SiO2 nanoparticles combines TiO2s photocatalytic property withnanosilicas physical barrier
DeFriend K.A., M.R. Wiesner & A.R. Barron, 2003. Alumina and aluminate ultrafiltration membranes derived from aluminananoparticles. J. Membr. Sci. 224(12), 1128.
TiO2 without SiO2 nanoparticles TiO2 with SiO2 nanoparticles
large surface areas and c
an be easily cleaned by back-flushing
Less pressure is required to pass
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Dendrimer-Enhanced Ultrafiltration (DEUF)
Dendritic polymers relatively monodispersed and highly branched
macromolecules with controlled composition and architecture consisting of
three components: a core, interior branch cells and terminal branch cell
removal of toxic metal ions, radionuclides, organic and inorganic solutes, bacteria & viruses
Poly(amidoamine) (PAMAM) dendrimers with ethylene diamine (EDA) core and terminal
NH2 to recover Cu(II) ions
high Cu(II) binding capacities than linear polymers with amine groups.
smaller intrinsic viscosities than linear polymers with same molar mass because of their
globular shape
comparatively smaller operating pressure and energy consumption could be achieved
FrechetJ.M.J. & D.A. Tomalia, (Eds.). 2001. Dendrimers and Other Dendritic Polymers. New York: Wiley and Sons..Diallo M.S., 2004. Water treatment by dendrimer enhanced filtration. US Patent Pending. Unpublished.
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Seawater Desalination
Process of removing salt from sea water for the production of pure water
USEPA standards and IS 10500: Drinking water TDS = 500 ppm
Membrane process like RO, NF,UF, MF
thermal desalination are the current desalination technologies
Energy intensive (cost and environmental impact)
Exploding energy costs and Inefficient energy utilization
Requirement of Huge amount of land area
CO2 emissions from the energy production
Warmer Waste brine discharge Imbalance of marine habitats
Reverse osmosis
Recovery limited to ~ 50%Brine discharge (environmental concerns)
Increased cost of pre-treatment
Use prime (electric) energy (~ 2.5 kWh/m 3)
Short membrane life time
Limited chemical selectivity & Incomplete rejection
Concentration polarization and membrane fouling
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Diameters in the nm range
Smooth and nearly-frictionless
Hydrophobic walls
Weak interactions with water Ultrafast transport of water
High water permeability and flux
Selectivity filter region with larger functionalgroups
Selective ion transport
Reduction in the cost of desalination
High permeability
Chemically inert membrane pore surface
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Limitations
Environmental fate and toxicity of a material
Difficult to remove from the water after treatment
Catalytic activity induce toxic effects when taken up by the cells
Microbial degradation induce unwanted nanoparticles enter into environment
High sorption capacity mobilises sequestered pollutants
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CONCLUSIONS
Nanotechnology offers much promise in water purification by monitoring,
wastewater treatment, desalination, and purification.
Application of water purification for drinking, disinfection, desalination, recycling
and remediation of polluted water.
Nanomaterials applied for water purification are carbon nanotubes,
nanomembranes, nanoclays, zeolites, nanoscale metals and nanofibers,
nanocatalysts, magnetic nanoparticles, nanosensors, etc.
Nano-technology could potentially lead to more effective means of faster, moreeconomical and more selective filtration
More research is needed for eliminating the limitations of toxicity of nanomaterials
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Diallo M.S., 2004. Water treatment by dendrimer enhanced filtration. US Patent Pending. Unpublished.
Frechet J.M.J. & D.A. Tomalia, (Eds.). 2001. Dendrimers and Other Dendritic Polymers. New York: Wiley and
Sons.
DeFriend K.A., M.R. Wiesner & A.R. Barron, 2003. Alumina and aluminate ultrafiltration membranes derived
from alumina nanoparticles. J. Membr. Sci. 224(12), 1128.
Qilin Li, Shaily Mahendra, Delina Y. Lyon, Lena Brunet, Michael V. Liga, Dong Li and Pedro J.J. Alvarez,
Antimicrobial nanomaterials for water disinfection and microbial control: Potential applications and
implications
Degradation of phenol by nanomaterial TiO2 in wastewater , Chemical Engineering Journal, Volume 119, Issue1, 1 June 2006, Pages 55-59
Parvaneh Sangpour, Fatemeh Hashemi, and Alireza Z. Moshfegh, Photoenhanced Degradation of Methylene
Blue on Cosputtered M:TiO2 (M ) Au, Ag, Cu) Nanocomposite Systems: A Comparative Study
Shengxiao Zhang, Hongyun Niu, Yuqi Lai, Xiaoli Zhao, Yali Shi, 2010, Arsenate and arsenite adsorption on
coprecipitated bimetal oxide magnetic nanomaterials: MnFe2O4 and CoFe2O4, Chemical Engineering Journel,158, 599-607
Cafer T. Yavuz J. T. Mayo, Carmen Suchecki, Jennifer Wang , Adam Z. Ellsworth, Helen DCouto, Elizabeth
Quevedo, Arjun Prakash, Laura Gonzalez, Christina Nguyen, Christopher Kelty, Vicki L. Colvin, 2010, Pollution
magnet: nano-magnetite for arsenic removal from drinking water, Environ Geochem Health
References
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Li Y.-H., J. Ding, Z.K. Luan, Z.C. Di, Y.F. Zhu, CL Xu, D.H. Wu & B.Q. Wei, 2003. Competitive adsorption
of Pb2+, Cu2+ and Cd2+ ions from aqueous solutions by multiwalled carbon nanotubes. Carbon 41(14),
27872792.
Karen E. Engates & Heather J. Shipley, 2010, Adsorption of Pb, Cd, Cu, Zn, and Ni to titanium dioxide
nanoparticles: effect of particle size, solid concentration, and exhaustion, Environ Sci Pollut Res.
X. Chen, Y. Dong, L. Fan, D. Yang, Anal. Chim. Acta 582 (2007)281.
W. Xu, J. Zhang, L. Zhang, X. Hu, X. Cao, J. Nanosci. Nanotechnol. 9 (2009) 4812.
Jiangnan Zhang, Zheng-Hong Huang, Ruitao Lv, Quan-Hong Yang, and Feiyu Kang, 2009, Effect of
Growing CNTs onto Bamboo Charcoals on Adsorption of Copper Ions in Aqueous Solution, Langmuir,
25 (1), 269-274
Yan-Hui Li, Jun Ding, Zhaokun Luan, Zechao Dia, Yuefeng Zhu, Cailu Xu, Dehai Wu and Bingqing Wei,
Competitive adsorption of Pb2+, Cu2+ and Cd2+ ions from aqueous solutions by multiwalled carbon
nanotubes , Carbon Volume 41, Issue 14, 2003, Pages 2787-2792
Xnemei Ren, Changhun Chen, Masaaki Nagatsu, Xiangke Wang, 2010, Carbon Nnaotubes as
adsorbents in environmenmtal pollution mamnagement: A review, Chemical Enginnering Journel.
Mangun C.L., Z.R Yue, J. Economy, S. Maloney, P. Kemme & D. Cropek, 2001. Adsorption of organic
contaminants from water using tailored ACFs Carbon. Chem. Mater. 13, 23562360.