nano water technology

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2. WATER NANAOTECHNOLOGY
BY
SULAIMAN ISHAQ MUKTAR
20162418
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3. TABLE OF CONTENT
• Introduction
• Applications of nanotech in water
• Adsorption
• Membrane
• Photocatalysis
• Disinfection and Microbial Control
• Sensing and Monitoring
• Journals
• Conclusion
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4. Why nanotechnology in Water?
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5. Introduction
• The growth of world’s population,is forecasted to be nearly doubled
from 3.4 billion in 2009 to 6.3 billion people in 2050,which leads to
the growth of human needs by up to about 70%, by 2050.
• Thus, the demand for fresh water is growing dramatically, in
particular for food production, since 70% of the world’s freshwater
withdrawals are already accounted for by agricultural irrigation
• Micropollutants are entering the water bodies through different
sources.
• As such diseases such as cholera, E. coli Infection, parasitic infections
and Typhoid fever are particularly prevalent among these societies
and amounts to higher percentage of death especially in children.
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7. • Current decontamination processes e.g chlorination and ozonation
consume a high amount of chemical agents and,produce toxic
byproducts.
• Water pollutants can be from
Biodegradable plant debris and animal waste
 Soil, silt
 Organic chemicals such as oil, plastics, pesticides, solvents, gasoline
 Nitrates and phosphates
 Heavy metals such as Lead, Mercury and Arsenic
Bacteria, viruses and parasites
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8. Nanotechnology for water treatment
• Nanotechnology give a lot opportunities to purify water even at ionic state
• Over the years scientists have looked at nano-enabled technologies to find a
solution to water treatment
• Nanotechnology has also gives completely new water purification
techniques as well.
• Nanomaterials have unique size-dependent properties related to their high
specific surface area (fast dissolution, high reactivity, strong sorption) and
discontinuous properties.
• Various nanomaterials can be used to make composite membranes
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11. • The application of nanotech in water can be through:
Drinking water treatment
Wastewater treatment
Remediation of contaminated water sources either surface or ground
water
• These could be through the following
1.Adsorption
2.Membrane
3.Photocatalysis
4.Disinfection and Microbial Control
5.Sensing and Monitoring
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12. 1.Adsorption
• Water treatment using adsorption
is by the removal of harmful pollutant from water by absorbing it in to
the surface of a nanomaterial.
• Adsorption is used for removal of organic pollutants and heavy metal
irons.
• Nanomaterials have extremely high specific surface area, high
concentration of sorption sites, tunable pore sizes and surface
chemistry which gives them a large boost in adsorption rate and
capacity
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13. • Carbon nanomaterials, metal oxide nanomaterials and nanofibers are among the
mostly researched materials for water purification by adsorption.
• CNT can be SWCNT and MWCNT made of graphene
• 1 .Carbon based nano adsorbents which includes
• a)Organic removal
 CNT have high efficiency
 High sorption capacity.
 Diverse contaminant interaction
 Organic compds which have –COOH,OH,-NH2 functional groups also forms
hydrogen bond with graphitic CNT surface
 Its surface area sorption on individual CNTs due to their external surface
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14. • B)Heavy metal removal
 Oxidized CNT have high sorption capacity for metal ions
 Surface functional groups are the major adsorption sites for metal
ions through electrostatic attraction and chemical bonding.
 CNT have unique applications in polishing steps to remove
recalcitrant compounds.
.
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15. • 11)Metal based Nano adsorbents
 Iron oxide,Titanium di oxide and alumina are effective adsorbents for
heavy metals
 Sorption is controlled by complexation between dissolved metal and the
oxygen in metal oxides.
Some iron oxide nanoparticles e.g nanomaghemite and nanomagnetite
can be superparamagnetic.
Metal oxide nanocrystals can be compressed into porous pellets without
significant compromising their surface area when moderate pressure is
applied.
Metal based nanomaterials remove variety of heavy metals such as AS
,Pb ,Hg,Cu,Cd,Cr,Ni.
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16. • 111) polymetric nano adsorbents
 Dendrimers are capable of removing both
organics and heavy metals.
 Interior shells can be hydrophobic for
sorption of organic compounds while exterior
branches for heavy metals adsoption
 Sorption is based on electrostatic
interactions,hydrophobic effect and hydrogen
bonding.
In water it is applied in powder form
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17. 2.MEMBRANES
• Membrane provide a physical barrier for such constituents based on
their size, allowing use of unconventional water sources.
• 1)Nanofiber membrane
 Electrospining is a simple,efficient and inexpensive way to make
ultra fine fibers using various materials eg polymers,ceramics or even
metals.
 NFs have specific surface area and porosity and form nanofiber mats
with complex pore structures.
 NF membranes can remove micron-sized particles from water
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18. Membranes
• Membrane separation processes are rapidly advancing applications
for water and wastewater treatment
• Membranes provide a physical barrier for substances depending on
their pore size and molecule size.
• Membrane technology is well established in the water and
wastewater area as a reliable and largely automated process.
• Also, Applied for the reduction of hardness, color, odor, and heavy
metal ions from groundwater.
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20. 3.Photocatalysis
• Photocatalysts are a special class of nanomaterial that can absorb
light and divert the absorbed energy to drive a chemical reaction
• Nanoscale Titanium dioxide and Zinc oxide are good examples of
photocatalytic nanoparticles and are among most widely used
materials in both research and practical applications
• Upon excitation by a photon (light particle) these nanomaterials can
produce a free electron and a hole in the nanoparticle.
• These charged particles will slowly migrate to the surface and will
interact with nearby organic molecules
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21. • Electron can drive a reduction reaction while hole will give rise to an
oxidation reaction.
• If a continuous supply of light is present, photogenerated electrons
and holes can completely reduce and oxidize a nearby organic
molecule to most elementary, carbon dioxide and water.
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22. • Photocatalysis is an AOP that is employed in the field of water and
wastewater treatment, in particular for oxidative elimination of
micropollutants and microbial pathogens.
• Persistent compounds like antibiotics or other micropollutants can be
degraded by photocatalysis
• Due to its high availability, low toxicity, cost efficiency, and well known
material properties, TiO2 is widely utilized as a photocatalyst
• When TiO2 is irradiated by ultraviolet light with an appropriate
wavelength in the range of 200–400 nm, electrons will be
photoexcited and move into the conduction band
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23. • Activation of TiO2 is usually induced by an ultraviolet lamp,or sunlight
• Besides TiO2, tungsten trioxide, and some fullerene derivatives eg.
Fullerol as well as composites with TiO2 have an photocatalytic effect
under visible light irradiation.53,54
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24. 4.Disinfection of water with nanomaterials
• Disinfection of water involves treatment for pathogenic microorganisms
using a chemical or/and physical approach.
• Major problems of common conventional disinfectants such as chlorine
treatment, ozone and UV water purification is the formation of disinfection
by products and high dosage requirements.
• Some of the nanomaterials show broad spectrum antimicrobial activity at
very low dosages making them great candidates for water disinfection
procedures.
• Nanomaterials such as nano silver, nano Zinc oxide, nano titanium dioxide,
nano cerium oxide, carbon nanotubes and fullerenes show strong
disinfection abilities without mechanisms involving strong oxidation
• these nanomaterials show lower tendencies to form toxic byproducts.
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25. Nanosilver and nano-titanium dioxide
• Although nanosilver exhibits a strong and broad-spectrum
antimicrobial activity, it has hardly any harmful effects in humans.
• It is already applied to point-of-use water disinfection systems and
antibiofouling surfaces
• Nano-titanium dioxide (TiO2), featuring high chemical stability and
low human toxicity at a cheap price, is utilizable in disinfection and
decontamination processes.
• The main advantage of nano-TiO2 over nanosilver is the nearly
endless life time of such coatings, since TiO2 as a catalyst remains
unchanged during the degradation process of organic compounds and
micro-organisms.
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26. 5.Sensor
• Usually SWCNT, MWCNTs nano wires( SnO2,ZnO),quantum dots are
used .
• Detection of Pathogens as well as numerous Microorganisms
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28. • To remove EDC (17β-Estradiol, 17α-ethinylestradiol, estrone,
estriol, and progesterone) from DW.
• Used UV Photolysis and Nanofilteration
• Intergrate the two processes
• The water matrix from a DWTP of 2.8 million people (pH 7.8)
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29. Uv,Nanofilteration and integrated process
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30. Uv after 6 hrs 30

31. Complete result of degradation
Compd Time (h) Degradation%
LP/UV Nanofiltration Integration
17β-estradiol 0.1 0 >99 99
3.0 30 81 86
6.0 56 84 85
17α-ethinylestradiol 0.1 5 >99 99
3.0 21 85 95
6.0 41 90 94
Estrone 0.1 21 >99 99
3.0 >95 70 93
6.0 >95 77 95
Estriol 0.1 6 99 99
3.0 29 93 89
6.0 53 94 91
Progesterone 0.1 27 >99 99
3.0 >95 89 99
6.0 >95 93 98 31

32. • Neither UV photolysis nor nanofiltration are the best treatment
technologies for all the compounds
• (17β-estradiol, 17α-ethinylestradiol, and estriol) were better removed
by nanofiltration and one by UV photolysis (estrone).
• A cocktail of numerous micropollutants that are also differently
removed by these technologies exists in water treatment utilities,
highlighting the benefits of having a multi-barrier approach.
• Using the intergrated process can treat a lot of pollutants
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34. Improved Adsorption Properties of a Nano
Zeolite adsorbent toxic Nitrophenols.
• Synthesized nano zeolites for removal of 3 nitrophenol isomers to
evaluate its feasibility as an effective adsorbent
• pH,contact time,adsorbent dose and initial conc.
• Equilibrium a@150mins
• Fits Freundlich isotherm,regeneration after 5 cycles
• Characterization with SEM,BET method,XRD,and ICP-OES
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36. (A) NZ (B)AC
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37. Effect of reaction time on nitrophenols adsorption by nano zeolite.
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39. Langmuir
isotherm
Freundlich
isotherm
Adsorbate
Qmax
(mg/g)
R2 1/n R2
o-
Nitrophenol
143.8 0.95 0.34 0.98
p-
Nitrophenol
156.6 0.92 0.24 0.97
m-
Nitropenol
121.7 0.94 0.56 0.99
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40. • NZ retained stable phases and the adsorption capacities of o-, p- and
m-nitrophenols were only decreased by 26.3, 21.8 and 29.1% from
their initial capacities.
• The required adsorption cost for treating 1000 kg wastewater
containing 300 mg/L of nitrophenols by using NZ was 46.6% lower
than that of AC.
• Based on these findings, NZ with high adsorption capacity and low
preparation cost can be used as an effective and economic adsorbent
for the removal of nitrophenols in wastewater systems
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41. Effective removal of heavy metal ions Cd2+, Zn2+, Pb2+, Cu2+ from aqueous
solution by polymer-modified magnetic nanoparticles Fei Ge,et al(2011).
• Fe3O4 magnetic nanoparticles (MNPs) modified with 3-
aminopropyltriethoxysilane(APS) and copolymers of acrylic acid (AA)
and crotonic acid (CA)
• characterized by TEM, XRD, infra-red spectra and thermogravimetric
analysis
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42. Transmission electron microscopy of magnetic nanoparticles. (a) Fe3O4,
(b) Fe3O4@APS, and (c) Fe3O4@APS@AA-co-CA.
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43. Effect of pH on adsorption and the
mechanism of adsorption
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44. Schematic representations of possible mechanism
for adsorption of metal ions by Fe3O4@APS@AA-
co-CA
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45. Effect of time on the adsorption of metal ions; adsorbent:
0.05 g, concentration of metal ions: 100 mg L−1, volume of
solution: 50 ml, pH: 5.5, at 298 K. 45

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47. • Fe3O4@APS@AA-co-CA MNPs are excellent for removal of heavy
metal ions such as Cd2+, Zn2+, Pb2+ and Cu2+ from aqueous
solution.
• Furthermore, the MNPs could efficiently remove the metal ions with
high maximum adsorption capacity at pH 5.5 and could be used as a
reusable adsorbent with convenient conditions.
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48. Thank you
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49. References
• Thi-Huong Pham, Byeong-Kyu Lee, Jitae Kim(2016) Improved adsorption properties of a nano zeolite
adsorbent toward toxic nitrophenols.Process safety and Environmental Protection 104.314-322
• Sandra Sanches, Alexandre Rodrigues,Vitor V. Cardoso,Maria J. Benoliel,João G. Crespo,Vanessa J.
Pereira(2016) Comparison of UV photolysis, nanofiltration, and their combination to remove hormones from
a drinking water source and reduce endocrine disrupting activity Environ Sci Pollut Res 23:11279–11288
• Fei Ge, Meng-Meng Li, Hui Ye, Bao-Xiang Zhao(2011). Effective removal of heavy metal ions Cd2+, Zn2+,
Pb2+, Cu2+ from aqueous solution by polymer-modified magnetic nanoparticles. Journal of Hazardous
Materials 211– 212 :366– 372
• Yang, K., Xing, B.S., 2010. Adsorption of organic compounds by carbon nanomaterials in aqueous phase:
Polanyi theory and its application. Chemical Reviews 110 (10), 5989e6008
• XIAOLEI QU, JONATHON BRAME, QILIN LI,PEDRO J. J. ALVAREZ(2012). Nanotechnology for a Safe and
Sustainable Water Supply: Enabling Integrated Water Treatment and Reuse
• Xiaolei Qu, Pedro J.J. Alvarez, Qilin Li (2013). Applications of nanotechnology in water and wastewater
treatment. water r e s e arch 4 7 :3 9 3 1 -3 9 4 6
• M. T. Amin, A. A. Alazba, and U.Manzoor (2014). A Review of Removal of Pollutants from Water/Wastewater
Using Different Types of Nanomaterials Advances in Materials Science and Engineering.
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