Application of Nanotechnology in water purification and oil spill removal

1. Central University Of Haryana
Course: Biophysics and Nanophysics
Topic: Applications of nanotechnology in water purification
and oil spill removal
Presented to
Dr.Ram Gopal Nitharwal
Department of
Biotechnology
Presented by
Smriti Ranjan
Msc Biotech(3rd sem)
221265

2. Content
Overview of Nanotechnology and
nanoparticles
Its use in water purification
Application in water purification
Application oil spill removal
Rferences

3. Nanotechnology is a multidisciplinary field of science, engineering, and
technology that deals with structures and devices on the nanometer
scale.
A nanometer (nm) is one billionth of a meter, which is roughly on the
scale of individual atoms and molecules.

4. Nanotechnology in water purification refers to the use of nanoscale materials and
processes to treat and purify water , improving its quality by removing contaminants ,
pollutants and pathogens .
This technology offers several advantages due to its unique properties at the nanoscale .
Nanoparticles:
•Small particles with dimensions typically less than 100 nm. Examples include
nanoparticles of metals, metal oxides, and quantum dots.

6. Nanomaterials, i.e., those materials which have at least one dimension in the 1–100
nm size range, have produced a new generation of technologies for water
purification.
This includes nanosized adsorbents, nanomembranes, photocatalysts, etc.
Stemming from extraordinary structural characteristics and size scale of
nanomaterials, the nanostructured membranes/adsorbents enable water purification
with a high efficiency in terms of pollutants removal and water permeability, thereby
reducing energy consumption and cost.
Nanomaterials offer several advantages for water treatment and control. This
amazing potential stems from their large exposed surface area and functionality that
can maximize their interactivity with water pollutants.

7. Water Purification:
1.Nanomaterial-based Filtration:
Membrane Filtration: Nanomaterials such as carbon nanotubes, graphene oxide, and nanoporous
membranes are employed to create ultrafiltration and nanofiltration membranes. These materials can
efficiently filter out contaminants, including bacteria, viruses, and pollutants, due to their high surface
area and unique properties at the nanoscale.

8. (a) Schematic shows diverse membrane filtration processes
including reverse osmosis, nanofiltration, ultrafiltration, microfiltration,
and particle filtration. Other than the reverse osmosis membranes
whose structure is almost dense and non-porous, the rest are different
in terms of the average pore size .
Nanofiltration and Reverse Osmosis:
Utilization of nanofiltration and reverse
osmosis membranes with nanoscale
pores for separating ions, salts, and
other contaminants from water. This
improves the efficiency of desalination
processes.
Reverse osmosis occurs when the water is moved across the membrane against
the concentration gradient, from lower concentration to higher concentration.
To illustrate, imagine a semipermeable membrane with fresh water on one side
and a concentrated aqueous solution on the other side. If normal osmosis
takes place, the fresh water will cross the membrane to dilute the
concentrated solution. In reverse osmosis, pressure is exerted on the side
with the concentrated solution to force the water molecules across the
membrane to the fresh water side.

9. 2.Nanoparticle-based Adsorption:
Metal Nanoparticles: Nanoparticles like silver,
titanium dioxide, and iron oxide have proven effective
in adsorbing and catalytically degrading contaminants
in water. They can bind with pollutants and facilitate
their removal through filtration or precipitation.

10. 3.Nano-Enhanced Water Treatment Chemicals:
Coagulants and Flocculants: Nanomaterials can improve the
performance of traditional water treatment chemicals. For instance,
nanoparticles like silica and aluminum oxide can enhance the
coagulation and flocculation process, improving the removal of
suspended particles.
Flocculation and Coagulation in water treatment are used
to remove suspended solids through a process that
destabilizes the suspended particles in water solutions.
The difference between the two is coagulation is the
coming together, or clumping of particles, and flocculation
is the settling of coagulated particles.

11. 4.Photocatalysis:
Titanium Dioxide Nanoparticles: These
nanoparticles can be used in photocatalytic water
treatment processes. When exposed to ultraviolet
(UV) light, titanium dioxide nanoparticles generate
reactive oxygen species, which can break down
organic pollutants and disinfect water.

12. 5.Nanomaterial-based Sensors:
Carbon Nanotube Sensors: Nanosensors can be
employed to detect and monitor contaminants in real-
time. Carbon nanotubes, for example, can be
functionalized to selectively detect specific pollutants,
providing a rapid and sensitive detection method.

13. 1) How Nanoparticles are used in water purification?
The highly porous nanoparticles, which are made to grab water and hold onto it like a
sponge, also reject dissolved salts and other contaminants. Additionally, the organic
substances and bacteria that eventually clog up conventional membranes are repelled by the
hydrophilic nanoparticles incorporated in the membrane.
2) How contaminated water can be purified by nanomaterials?
Nanotechnology-based water filtration makes use of microscopic components like carbon
nanotubes and alumina fibres. Additionally, it makes use of nanoporous zeolite filtration
membranes, nanocatalysts, and magnetic nanoparticles.
3) Which nanoparticles are used for purification of water?
Zero-valent metal nanoparticles, metal oxide nanoparticles, carbon nanotubes (CNTs), and
nanocomposites are now the most thoroughly investigated nanomaterials for the treatment
of water and wastewater.

14. Oil Spill Removal:
1.Nanoparticle Dispersants:
1. Use of nanomaterial-based dispersants to break down oil
into smaller droplets, enhancing microbial degradation
and making it easier for natural processes to eliminate
the oil. Nanoparticles like graphene oxide and clay
nanoparticles have shown promise in this regard.
The presence of XG of silicafavors the adsorption nanoparticles at the oil–
seawater interface and also is considerably effective in enhancing the
viscosity of continuous phase.

15. 2. Nanomaterial Sorbents:
Deployment of nanomaterials like carbon nanotubes,
aerogels, and magnetic nanoparticles as sorbents for
oil spill cleanup. These materials can absorb large
quantities of oil and are often reusable.

16. 3.Nanoemulsions:
Formation of stable nanoemulsions with
nanoscale oil droplets to improve the
efficiency of oil recovery. Nanoemulsions
can be used to encapsulate and transport
oil for easier collection.
4. Smart Nanomaterials:
Development of smart nanomaterials that
respond to environmental conditions, such
as temperature or pH changes, to facilitate
the controlled release of oil-capturing
agents.

17. 5.Nanorobots for Cleanup:
Exploration of nanorobots or nanomachines designed to
selectively target and remove oil pollutants from water
surfaces. These tiny devices could offer precision in oil
spill cleanup.
Nanorobots offer a more efficient solution.
Researchers at MIT have developed a type of
nanorobot that can magnetically separate oil and
water, a crucial advancement considering that the
largest oil spill in history, the Deepwater Horizon
spill, released an estimated 4.9 million barrels of
oil into the Gulf of Mexico.
Microbots’ structure consists of nanosized multilayers of graphene oxide, nickel, and
platinum, providing different functionalities. The outer layer of graphene oxide captures
lead on the surface, and the inner layer of platinum functions as the engine
decomposing hydrogen peroxide fuel for self-propulsion, while the middle layer of
nickel enables external magnetic control of the microbots. Mobile GOx-microbots
remove lead 10 times more efficiently than nonmotile GOx-microbots, cleaning water
from 1000 ppb down to below 50 ppb in 60 min

18. References
www.Youtube.com
https://watermanaustralia.com/use-of-
nanoparticles-in-water-purification
www.sciencedirect.com
https://pubs.acs.org