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Presented byMusale Baliram S
M. Pharmacy
(Pharmaceutics)

Department of Pharmaceutical
Sciences , RTMNU Nagpur.
2
Green Chemistry is the
utilization of a set of
principles that reduces
or eliminates the use or
generation of hazardous
substances
in
the
design, manufacture and
application of chemical
products .
Green Chemistry Is About
Waste
Material
Hazard
Risk
Energy
Cost

4
Chemistry is undeniably a very prominent part

of our daily lives.
Chemical developments also bring new
environmental
problems
and
harmful
unexpected side effects, which result in the
need for ‘greener’ chemical products.
A famous example is the pesticide DDT.
The

Green
Chemistry
program
supports the invention of more
environmentally
friendly
chemical
processes which reduce or even
eliminate the generation of hazardous
substances.
This program works very closely with
the twelve principles of Green
Chemistry.
“It is better to prevent waste than to
treat or clean up waste after it is
formed”
» Atom Economy
Synthetic methods should be
designed
to
maximize
the
incorporation of all the materials
used in the process into the final
product.
» Less Hazardous Chemical Synthesis
Wherever practicable, synthetic
methods should be designed to use
and generate substances that
possess little or no toxicity to
people or the environment.
 Designing Safer Chemicals

Chemical products should be designed
to effect their desired function while
minimizing their toxicity.
  Safer Solvents and Auxiliaries
The use of auxiliary substances (e.g.,
solvents or separation agents) should not
be made unnecessary whenever possible
and innocuous when used.
  Design for Energy Efficiency
Energy requirements of chemical
processes should be recognized for their
environmental and economic impacts and
should
be
minimized.
If
possible,
synthetic methods should be conducted at
ambient temperature and pressure.


Use of Renewable Feedstocks

A raw material or feedstock
should be renewable rather than
depleting whenever technically and
economically practicable.



Reduce Derivatives

Unnecessary derivatization (use of
blocking
groups,
protection/deprotection,
and
temporary
modification
of
physical/chemical
processes) should be minimized or
avoided if possible, because such
steps require additional reagents and
can generate waste.



Catalysis

Catalytic reagents (as selective as
possible)
are
superior
to
stoichiometric reagents.


Design for Degradation

Chemical products should be designed
so that at the end of their function
they break down into innocuous
degradation products and do not
persist in the environment.



Real-time Analysis for Pollution
Prevention
Analytical methodologies need to be
further developed to allow for realtime, in-process monitoring and control
prior to the formation of hazardous
substances.



Inherently Safer Chemistry
for Accident Prevention

Substances and the form of a
substance used in a chemical process
should be chosen to minimise the
potential for chemical accidents,
including releases, explosions, and
fires.
The major uses of GREEN CHEMISTRY
 Saving Energy
 Minimum Global Changes
 Minimize the Depletion
of Resources
 Food Supply
 Releasing Non-Toxic
in the Environment

13
1.Saving Energy
Green Chemistry will be essential in

Developing the alternatives for energy
generation (photovoltaic's, hydrogen, fuel
cells, biogases fuels, etc.)
WHAT IS HYDROGEN ECONOMY ?
The hydrogen economy describes a
system in which our energy needs
are
predominantly
met
by
hydrogen, rather than fossil fuels.
This type of economy would rely on
renewable resources in the form of
hydrogen gas and water, drastically
changing pollution , electricity
sources, infrastructure, engines,
and international trade, without
impacting our quality of life. In a
hydrogen economy, vehicles like
cars
and
airplanes
use
hydrogen fuel
cells for
power,
rather than petroleum distillates.
USES OF HYDROGEN

Hydrogen is a very useful gas.
1) It is used as a fuel
2) It makes ammonia, NH4
3) It is used to make plastic (PV)
4) It also turns liquid vegetable
oils into margarine (vegetable
ghee)

Hydrogen Gas filling in Car
ADVANTAGES OF HYDROGEN
•Waste product of burning H2 is water.
•Elimination of fossil fuel pollution.
•Elimination of greenhouse gases.
•Elimination of economic dependence.
2.Resource Depletion
 Due

to the over
utilization of nonrenewable resources,
natural
resources
are being depleted
at an unsustainable
rate.
 Fossil fuels are a
central issue.
Minimize the Depletion of Resources
Renewable

resources can be
made
increasingly
viable
technologically and economically
through green chemistry.






Biomass
Nano science & technology
Solar Energy
Carbon dioxide
Waste utilization
3.Minimum Global Changes
Concerns for climate change, oceanic
temperature, and global distillation can
be addressed through the development
and implementation of green chemistry
technologies.
4.Food Supply

While current food levels are sufficient, but the
distribution is inadequate
 Agricultural methods are unsustainable
 Future food production intensity is needed.
 Green chemistry can address many
food supply
issues

 Green

developing:
 Pesticides

chemistry

is

which only affect
target organisms and degrade
to innocuous by-products.
 Fertilizers
and
fertilizer
adjuvant that are designed to
minimize
usage
while
maximizing effectiveness.
 Methods of using agricultural
wastes for beneficial and
profitable uses.
5. Releasing Non-Toxics in the Environment
Substances
that
are
toxic to humans, the
biosphere and all that
sustains it, are currently
still being released at a
cost of life, health and
sustainability.

One
of
green
chemistry’s
greatest
strengths is the ability
to design for reduced
hazard.

 Business benefits of green chemistry

include: improved resource efficiency
and lower raw material and utility bills
 Reduced waste treatment and disposal
costs.
 Ability
to
capitalize
on
the
environmental technology marketplace
by designing new, 'greener' products
 Improved health and safety for staff
and customers
 Environmental benefits include: fewer
raw materials and natural resources
used.
 Lower levels of chemicals released to
the environment
 Cleaner production technologies
 Reduced emissions and product impacts
DRY CLEANING OF CLOTHES
Tetra

chloroethene(C2Cl2) was earlier
used as solvent for dry cleaning but these
compound contaminates the ground water
and suspected carcinogen.
The process using this compound is now
being replaced by a process where
liquefied carbon dioxide with a suitable
detergent is used .
Replacement of halogenated solvent by
liquid Carbon dioxide (CO2) will result in
less harm to ground water .
BLEACHING OF PAPER
Chlorine

gas was used
earlier for bleaching of
paper .
These
days
hydrogen
peroxide
with
suitable
catalyst which promotes
the bleaching action of
hydrogen peroxide is used .
SYNTHESIS OF CHEMICALS
Ethanol (CH3CHO) is now
commercially prepared by one
step oxidation of Ethene in
the presence of ionic catalyst
in aqueous medium with a
yield of 90%
Introduction to green chemistry

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Introduction to green chemistry

  • 1. Presented byMusale Baliram S M. Pharmacy (Pharmaceutics) Department of Pharmaceutical Sciences , RTMNU Nagpur.
  • 2. 2
  • 3. Green Chemistry is the utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture and application of chemical products .
  • 4. Green Chemistry Is About Waste Material Hazard Risk Energy Cost 4
  • 5. Chemistry is undeniably a very prominent part of our daily lives. Chemical developments also bring new environmental problems and harmful unexpected side effects, which result in the need for ‘greener’ chemical products. A famous example is the pesticide DDT.
  • 6. The Green Chemistry program supports the invention of more environmentally friendly chemical processes which reduce or even eliminate the generation of hazardous substances. This program works very closely with the twelve principles of Green Chemistry.
  • 7.
  • 8. “It is better to prevent waste than to treat or clean up waste after it is formed”
  • 9. » Atom Economy Synthetic methods should be designed to maximize the incorporation of all the materials used in the process into the final product. » Less Hazardous Chemical Synthesis Wherever practicable, synthetic methods should be designed to use and generate substances that possess little or no toxicity to people or the environment.
  • 10.  Designing Safer Chemicals Chemical products should be designed to effect their desired function while minimizing their toxicity.   Safer Solvents and Auxiliaries The use of auxiliary substances (e.g., solvents or separation agents) should not be made unnecessary whenever possible and innocuous when used.   Design for Energy Efficiency Energy requirements of chemical processes should be recognized for their environmental and economic impacts and should be minimized. If possible, synthetic methods should be conducted at ambient temperature and pressure.
  • 11.  Use of Renewable Feedstocks A raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable.  Reduce Derivatives Unnecessary derivatization (use of blocking groups, protection/deprotection, and temporary modification of physical/chemical processes) should be minimized or avoided if possible, because such steps require additional reagents and can generate waste.  Catalysis Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.
  • 12.  Design for Degradation Chemical products should be designed so that at the end of their function they break down into innocuous degradation products and do not persist in the environment.  Real-time Analysis for Pollution Prevention Analytical methodologies need to be further developed to allow for realtime, in-process monitoring and control prior to the formation of hazardous substances.  Inherently Safer Chemistry for Accident Prevention Substances and the form of a substance used in a chemical process should be chosen to minimise the potential for chemical accidents, including releases, explosions, and fires.
  • 13. The major uses of GREEN CHEMISTRY  Saving Energy  Minimum Global Changes  Minimize the Depletion of Resources  Food Supply  Releasing Non-Toxic in the Environment 13
  • 14. 1.Saving Energy Green Chemistry will be essential in Developing the alternatives for energy generation (photovoltaic's, hydrogen, fuel cells, biogases fuels, etc.)
  • 15. WHAT IS HYDROGEN ECONOMY ? The hydrogen economy describes a system in which our energy needs are predominantly met by hydrogen, rather than fossil fuels. This type of economy would rely on renewable resources in the form of hydrogen gas and water, drastically changing pollution , electricity sources, infrastructure, engines, and international trade, without impacting our quality of life. In a hydrogen economy, vehicles like cars and airplanes use hydrogen fuel cells for power, rather than petroleum distillates.
  • 16. USES OF HYDROGEN Hydrogen is a very useful gas. 1) It is used as a fuel 2) It makes ammonia, NH4 3) It is used to make plastic (PV) 4) It also turns liquid vegetable oils into margarine (vegetable ghee) Hydrogen Gas filling in Car
  • 17. ADVANTAGES OF HYDROGEN •Waste product of burning H2 is water. •Elimination of fossil fuel pollution. •Elimination of greenhouse gases. •Elimination of economic dependence.
  • 18. 2.Resource Depletion  Due to the over utilization of nonrenewable resources, natural resources are being depleted at an unsustainable rate.  Fossil fuels are a central issue.
  • 19. Minimize the Depletion of Resources Renewable resources can be made increasingly viable technologically and economically through green chemistry.      Biomass Nano science & technology Solar Energy Carbon dioxide Waste utilization
  • 20. 3.Minimum Global Changes Concerns for climate change, oceanic temperature, and global distillation can be addressed through the development and implementation of green chemistry technologies.
  • 21. 4.Food Supply While current food levels are sufficient, but the distribution is inadequate  Agricultural methods are unsustainable  Future food production intensity is needed.  Green chemistry can address many food supply issues 
  • 22.  Green developing:  Pesticides chemistry is which only affect target organisms and degrade to innocuous by-products.  Fertilizers and fertilizer adjuvant that are designed to minimize usage while maximizing effectiveness.  Methods of using agricultural wastes for beneficial and profitable uses.
  • 23. 5. Releasing Non-Toxics in the Environment Substances that are toxic to humans, the biosphere and all that sustains it, are currently still being released at a cost of life, health and sustainability.  One of green chemistry’s greatest strengths is the ability to design for reduced hazard. 
  • 24.  Business benefits of green chemistry include: improved resource efficiency and lower raw material and utility bills  Reduced waste treatment and disposal costs.  Ability to capitalize on the environmental technology marketplace by designing new, 'greener' products  Improved health and safety for staff and customers  Environmental benefits include: fewer raw materials and natural resources used.  Lower levels of chemicals released to the environment  Cleaner production technologies  Reduced emissions and product impacts
  • 25.
  • 26. DRY CLEANING OF CLOTHES Tetra chloroethene(C2Cl2) was earlier used as solvent for dry cleaning but these compound contaminates the ground water and suspected carcinogen. The process using this compound is now being replaced by a process where liquefied carbon dioxide with a suitable detergent is used . Replacement of halogenated solvent by liquid Carbon dioxide (CO2) will result in less harm to ground water .
  • 27. BLEACHING OF PAPER Chlorine gas was used earlier for bleaching of paper . These days hydrogen peroxide with suitable catalyst which promotes the bleaching action of hydrogen peroxide is used .
  • 28. SYNTHESIS OF CHEMICALS Ethanol (CH3CHO) is now commercially prepared by one step oxidation of Ethene in the presence of ionic catalyst in aqueous medium with a yield of 90%