1. ELECTRIFIED NANO FILTER
AN UPRISING FILTRATION TECHNIQUE
USING NANOTEHNOLOGY
N.V.N.S.Srikar1
1. B.Tech Third year ECE,
Pragati Engineering College.
Ph No: 9505454446
Registration ID:
0126130958
G.S.Charan teja2
2. B.Tech Third year ECE,
Pragati Engineering College.
Ph No: 9640943863
Registration ID: 0126131135
T.Satish Kumar3
3. B.Tech Third year ECE, Pragati
Engineering College.
Ph No: 9533374228
Registration ID: 0126143122
Abstract--- Contrary to the past, our recent
developed technological society has made miracles to
our life. In response to the rapidly changing face of
technology and demand for physically smaller with
greater efficiency in every requirement .This
presentation is about a technology which is
continuously revolutionizing, making exciding
breakthroughs in every field. This technology was
coined as Nanotechnology, one of the leapfrogging
technologies on the crossroads of the 21st
century.
Our natural heritage rivers, seas and oceans has been
exploited, mistreated and contaminated and which is
becoming predominant issue in India in these recent
years and leading to death of over one lakh people
annually and making around 70 million suffering
with many waterborne diseases.
In this paper we will mainly accentuate you
about the construction of an“ELECTRIFIEDNANO
FILTER” from exploiting nanotechnology so that
how it can be employed as a water purification
system.
Keywords: revolutionizing, exploited, accentuate
Nanotechnology, purification
1) INTRODUCTION:
1.1) what is nano technology? :
Nanotechnology is the manipulation of matter on
atomic and molecular scale. It deals with
developing materials, devices, or other structures
possessing at least one dimension sized from 1 to
100 nanometers.
A nanometer is one-billionth of a meter,
smaller than the wavelength of visible light or
about one ten-thousandth of the thickness of a
human hair. The concepts that seeded
nanotechnology were first discussed in 1959 by
renowned physicist Richard Feynman in his talk
“There's Plenty of Room at the Bottom”
Later with the discovery of fullerenes in
1985 by Kroto, Heath, O’Brien, Curl, and Smalley
and the facile synthesis developed by Kraetschmer
a new class of molecules has been discovered that
build up closed cages. The most well-known
representative of this new allotrope is the C60-
molecule which is nanometer in diameter with a
remarkable discovery that has puzzled and
amplified the advancement in the nanotechnology
research.
1.2) Water – borne diseases in India:
With two thirds of the earth surface
covered by water and the human body consisting of
75 percent of it, it is evidently clear that water is
one of the prime elements responsible for life on
earth. Water covers 71% of earth surface of which
only 0.3% is fresh water
When it comes to water and sanitation in
India our natural heritage (rivers, seas and oceans)
has been exploited, mistreated and contaminated
due to this out of 1.42 million villages in India,
1,96,813 are effected by contamination of water,
72% of rural India has no improved sanitation
facilities and ground water in one –third of India’s
647 districts is not fit for drinking due
concentration of chemicals exceeds the tolerance
levels and in turn becoming victims to the water

2. borne diseases, which account for about 80% of
sickness in India and leading to death of over one
lakh people annually and making 70 million sufferers
to these diseases. A world resources report sated that
about 70% percent of India’s water supply, is
seriously polluted with sewage effluents. According
to UN report: India’s water quality is poor- it ranks
120th
among 122 nations in terms of quality of water
available to its citizens.
2) NANO FILTERS:
The purpose of a water filter is to screen out
harmful stuff and mechanical filtration is currently the
most common method of cleansing water. Filters use
a mechanical process meaning the particles are trapped
in a very fine porous element and prevented from
coming out the clean water end. The general criteria for
a filter are: 1) Pore Size, 2) Pump Force, 3)Cost 4)
Serviceability. The Nanofiltration (NF) is a cross-flow
filtration technology which ranges somewhere
between ultra filtration (UF) and reverse osmosis (RO).
The nominal pore size of the membrane is typically
about 1 nanometer. In much of the developing world,
clean drinking water is hard to come by, and
nanotechnology provides one solution. While Nano
filtration is used for the removal of contaminants from a
water source, it can also commonly used
for desalination. The recent development in
nanofiltration process is the usage of electricity with
nanofiltration can completely wipe out the chemicals
and viruses, bacteria etc in water.
2.1) Principle of Electrified Nano filter:
The electrified Nano filter is a textile based
multiscale device which use the principle of electrical
sterilization of water using silver Nano wires, carbon
Nano tubes &cotton. The key is coating the filter fabric –
ordinary cotton-with nanotubes and silver nanowires, and
then electrifying it. This approach, which combines
several materials spanning three very different
Fig 1: Principle of filtration
length scales with simple dying based fabrication,
makes a gravity fed device operating at 100000L/h-
m2.It’s inexpensive ,is very resistant to clogging, and
uses much less electricity than systems that require
the water to be pumped through them.
2.2) SYNTHESIS OF CARBON NANOTUBES:
Nanotube is the member of
the fullerene structural family. Their name is derived
from their long, hollow structure with the walls
formed by one-atom-thick sheets of carbon,
called graphene
Carbon nanotubes (CNT’s) have been under
scientific investigation for more than fifteen years
because of their unique properties that predestine
them for many potential applications.
Fig 2: image of nanotubes
Carbon nanotube properties depend on how
you roll the sheet. Because of sp2 bonds are
composed entirely these bonds are stronger than the
sp3 in diamond, provide nanotubes with unique
strength .There are three unique geometries of carbon
nanotubes also referred to as flavors. The three
flavors are armchair, zigzag, and chiral with right
arrangement of carbon atoms, carbon nanotubes are
hundred times stronger than steel but 6 times lighter
in weight.
a) ARC DISCHARGE METHOD :
Arc discharge method is the most common
and easiest way to produce CNT’s,
creates CNT’s through arc-vaporization of two
carbon rods placed end to end, A chamber containing
a graphite cathode and anode contains evaporated
carbon molecules in a buffer gas such as helium&
also contains some amount of metal catalyst particles
such as cobalt, nickel,. DC current of 50 to 100A is
driven by a potential difference of approximately 20
V passed through the chamber while the chamber is
also pressurized and heated to ~4000K. about half of
the evaporated carbon solidifies on the cathode tip
into a "cylindrical hard deposit." The remaining
carbon condenses into "chamber soot" around the
walls of the chamber and "cathode soot" on the
cathode. It yields either single-walled or multi-walled
carbon nanotubes The advantage of this method is

3. that it produces a large quantity. But the main
disadvantage is that there is relatively little control over
the alignment of the produced nanotubes, which is
critical to their characterization and role. Furthermore,
due to the metallic catalyst included in the reaction, and
requires further purification - to separate
the CNT’s from the soot Methods such as oxidation,
centrifugation, filtration, and acid treatment have been
used.
Fig 3:mechanishm of arc discharge
b) LASER ABLATION: Laser ablation is the process
of removing material from a solid (or occasionally
liquid) surface by irradiating it with a laser beam. At
low laser flux, the material is heated by the absorbed
laser energy and evaporates or sublimates A quartz tube
containing a block of graphite is heated in a furnace. A
flow of argon gas is maintained throughout the reaction.
A laser is used to vaporize the graphite within the
quartz. The carbon vaporizes, is carried away by the
argon, and condenses downstream on the cooler walls
of the quartz. Nanotubes develop on the cooler surfaces
of the reactor as the vaporized carbon condenses. The
laser ablation method yields around 70% and produces
primarily single-walled carbon nanotubes (SWNT’S).
Fig 4: mechanism in laser ablation
c) CHEMICAL VAPOR DEPOSITION
(CVD): Chemical vapor deposition is a chemical
process used to produce high-purity, high-
performance solid materials. The CVD method
extends this idea by embedding these metallic
particles (iron, in the case of the seminal paper) in
properly aligned holes in a substrate (silicon, in this
case). a substrate is prepared with a layer of metal
catalyst articles, most commonly nickel, cobalt,
iron, or a combination. Essentially, tubes are
drilled into silicon and implanted with iron nano
particles at the bottom. Then, a hydrocarbon such
as acetylene is heated and decomposed onto the
substrate. The carbon comes into contact with the
metal particles embedded in the holes and starts to
form nanotubes that are "templated" from the shape
of the tunnel. It turns out that the carbon nanotubes
grow very long and very well aligned, in the angle
of the tunnel.
Fig 5: mechanism in CVD
2.3) SYNTHESIS OF SILVER
NANOWIRES:
a) Physical vapor deposition (PVD) : It describes a
variety of vacuum deposition methods used to
deposit thin films by the condensation of a vaporized
form of the desired film material onto various work
piece surfaces The coating method involves purely
physical processes such as high-temperature

4. vacuum evaporation with subsequent condensation
b) Laser ablation: It is the process of removing
material from a solid (or occasionally liquid) surface by
irradiating it with a laser beam. At low laser flux, the
material is heated by the absorbed laser energy and
evaporates or sublimates
Chemical Approach: The most common approach for
synthesis of silver nanoparticles is chemical reduction
by organic and inorganic reducing agents. In general,
different reducing agents such as sodium borohydride,
elemental hydrogen, polyol process, Tollens reagent
and the tri sodium citrate reduction. A large excess of
sodium borohydride is needed both to reduce the ionic
silver and to stabilize the formed nanoparticles. The
silver nitrate reduction reaction can be written as
AgNO3 + Na BH4 
Ag +0.5 H2 +0.5 B2H6 + N aNO3
Fig 2.Electron microscope image of silver nanowires
3) MAKING AND PROCESS OF FILTRATION:
The research was initially started with basic
criteria of designing and introducing a filter that
could provide an affordable, clean and low cost
drinking water
Initially they started with basic cotton as
their key source of filter as it is a material which is
very economical in terms of cost, durable & widely
available
Silver has long been known to cultures all
around the world for many centuries to have anti
microbial& bacterial properties to kill bacteria. And
at nanometer scale the anti bacterial property of the
silver has enhanced & it possesses the
highest electrical conductivity of any element
And recent research found that carbon nano
tubes were good conductors of electricity .so the
researchers reasoned the two materials in concert
would be effective against bacteria and other viruses
and chemicals. So they treated the cotton with silver
nanoparticles and added a layer of carbon nanotubes
to increase the filter’s electricalconductivity.
With a continuous structure along the
length, you can move the electrons very efficiently
and really make the filter very conducting .with a
serious of experiments with the final coated filter by
running with various strengths of electrical current
they finally operated at 20 volts which gave them the
required results. .
The big advantage of the nanomaterials is
that their small size makes it easier for them to stick
to the cotton. The nanowires range from 40 to 100
billionths of a meter in diameter and up to 10
millionths of a meter in length. The nanotubes were
only a few millionths of a meter long and as narrow
as a single billionth of a meter. Because the
nanomaterials stick so well, the nanotubes create a
smooth, continuous surface on the cotton fibers. The
longer nanowires generally have one end attached
with the nanotubes and the other end branching off,
poking into the void space between the cotton fibers.

5. Fig.3.process of filtration
Process in general filters that physically trap bacteria
and allow the clean water .but this filter instead of
physically trapping bacteria; it lets them flow on
through the water. But by the pathogens have passed
through, the device kills them as an electrical field of
20v runs through the highly conductive “Nano
coated” cotton.
4) COMPARISON WITH OTHER FILTRATION
PROCESS:
This table gives the information about the
nanofiltration with other filtration techniques:
(-) = not effective, (+) = low effectiveness,(++) =
moderate effectiveness, (+++) = high effectiveness,
(++++) = very high effectiveness
4.2) ADVANTAGES:
• Purifies water at low cost.
• Process of filtration is 80,000 times faster
than existing filters.
• Uses less voltage to kill bacteria and
viruses.
• Can be easily used even in remote areas.
• Water flows through filter is quickly &
easily due to large pores
• No clogging problem.
• No bio fouling
• Low electricity requirement.
4.3) DISADVANTAGES:
• Cannot wipeout some of the chemicals.
• A single filter can only kill 98% of the
bacteria.
• Traces of silver particles & CNT residue
5) CONCULSION:
By adapting to this electrified
nano filtration process we can improve the
prevailing situation faced in the purification of
water as it can be used from macro (national &
state) level to the micro (district & village) level
6)BIBLIOGRAPHY:
Different
filtration
process
protozoa Bacteria viruses chemicals
Micro
filtration ++++ ++
- -
Ultra
filtration ++++ ++++ ++ +
Nano
filtration ++++ ++++ ++++ ++
Reverse
osmosis ++++ ++++ ++++ +++
Distillation
systems ++++ ++++ ++++ ++
Uv
filtration
systems
++++ ++++ +++
-

6. 1. http://news.stanford.edu/news/2010/august/n
ano-pure-water-083110.html
2. http://pubs.acs.org/doi/abs/10.1021/nl10194
4e?journalCode=nalefd
3. http://www.waterfilterdude.com/water-
filter.shtml
4. http://www.deccanherald.com/content/6374
0/poor-water-quality-serious-threat.html
5. http://www.onlymyhealth.com/top-water-
related-diseases-in-india-1300271205
6. http://in.reset.org/blog/water-borne-diseases-
india

7. 1. http://news.stanford.edu/news/2010/august/n
ano-pure-water-083110.html
2. http://pubs.acs.org/doi/abs/10.1021/nl10194
4e?journalCode=nalefd
3. http://www.waterfilterdude.com/water-
filter.shtml
4. http://www.deccanherald.com/content/6374
0/poor-water-quality-serious-threat.html
5. http://www.onlymyhealth.com/top-water-
related-diseases-in-india-1300271205
6. http://in.reset.org/blog/water-borne-diseases-
india