Use of Nanotechnology

in Wastewater
treatment

M V R S C Pavan Kumar
B Ganesh
Department of Chemical
Engineering,Anurag Group of
Institutions,Telangana
Abstract:
● Water is an essential substance in all of our lives and sustainable and
cost efficient purification is very important to ensure that there is
regular supply of safe and contaminant free water.
● Nanotechnology and nano materials are proving to be a very efficient
way of treating wastewater. It has many advantages over other
conventional methods.
● These nanomaterials have applications in water purification and
water treatment devices, owing to their effectiveness against both
chemical and biological contaminants.
What is Nanotechnology,and what’s fascinating
about it?
Nanotechnology is "Research

and technology development at the atomic, molecular or

macromolecular levels, in the length scale of approximately 1

- 100 nanometer range, to provide a fundamental

understanding of phenomena and materials at the nanoscale

and to create and use structures, devices and systems that have

novel properties and functions because of their small and/or immediate

size.
Why water should be treated with
nanoparticles?
● Common constituents of wastewater are pathogenic and
non-pathogenic microorganisms, organic substances such as
excreta, plants material, food, protein, and inorganic substances like
metal particles, ammonia along with gases.
● Most of the traditional technologies for water treatment, such as
activated carbon adsorption and common chemical oxidation, are
effective but very often are costly and time-consuming.
● Biological degradation is environmentally friendly and cost-effective,
but it is usually time-consuming.

The ability to remove toxic contaminants from these environments

to a safe level and doing so rapidly, efficiently and within reasonable
costs is important and Nanotechnology could play an important role
in this regard.
Types of Nanomaterials used

● Nanomembranes
○ Nanomembranes such as NF and RO can filter
smallest organisms (bacteria and viruses) and
molecules with faster water flow than conventional
filter owing to their capability for separation at
molecular scale.
● Nanoparticles
○ Nano-sized particles are particularly attractive for
catalysis due to their high reactivity, attributed to
enhanced surface area.Nanoparticles of
semiconductors are of great attention due to novel
properties compared to their bulk materials.
● Magnetic nanoparticles
○ These especially suited for decomposing organic
pollutants and removing salts and heavy metals from
liquids.Owing to their strong magnetic properties,
magnetic nanomaterials act not only as an adsorbent
to remove target compounds from contaminated
water, but also as a magnetic element to attract and
retain the elements, which can be removed from
solutions.This make economically attractive for
industrial users.
● Bioactive nanoparticles
○ Nanotechnologies present a reasonable alternative
for development of new chlorine-free biocides,since
there is a big threat of waterborne infectious
diseases, especially in the developing world.Being
made up of many atoms of silver in the form of silver
ions, they have high surface reactivity and strong
antimicrobial properties,used for water purification.
● Nanosensors
○ Nanosensors can detect single cells
or even atoms, making them far
more sensitive than counterparts
with larger components.Detection
technology for water purification
would allow people to have a quick
check to find out the contaminants
without sending samples to
laboratories for testing.

Apart from these, other aspects of

nanotechnology in water treatment
include nanofilters from zeolites,
attapulgite clays and nanoporous
polymers.
 Nanofilters from zeolites

Attapulgite clay

Iron nanoparticles CNTs

Advantages Disadvantages

1. Purify water with a low expense 1. Aggregation of nanoparticles

2. High working efficiency in removing
2. Water contamination by leaching of nano
pollutants and reusable ability
composites

3. Human toxicity due to skin exposure of nano

particles

4. Difficulties in disposing nano wastes

Final Point…….

Industrialization and population are the main reasons for increase in amount wastewater.
These are also the main areas which require regular supply of clean water. Several methods
are employed to ensure a sustained supply of water for the requisite purposes.
Nanotechnology is also being looked upon to provide an economical, convenient and
ecofriendly means of wastewater remediation. Different types of nanoparticles such as
nanosized metals, metal oxides, zerovalent ions, nanofiltration membranes have proven
effective in detection, removal and/or destruction of contaminants.
References:
1. Nanotechnology in Water treatment:an
emerging trend
2. Application of Nanotechnology for waste
management: Challenges and limitations
3. Nanomaterials Use in Wastewater
Treatment
4. An Overview of Nanomaterials for Water
and Wastewater Treatment
5. Textbook of Nanoscience and
nanotechnology