GREEN CHEMISTRY

Presented by

1.Payal Shukla-(Roll no-48)

2.Akshata Upadhaya-(Roll no-30)

3.Sharmilee Ghosh-(Roll no-38)

4.Subhashini thevar-(roll no -45)

5.Khushbu gautam-(Roll no-46)

6.Deepika sarad(Roll no-50)

7.Geeta anchan-(Roll no-32)

F.Y.J.C Science

JH PODDAR ENGLISH MEDIUM HIGH SCHOOL & JUNIOR COLLEGE

GREEN CHEMISTRYWhat is green chemistry?

Green Chemistry is the utilisation 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 Minimisation at Source

• Use of Catalysts in place of Reagents

• Using Non-Toxic Reagents

• Use of Renewable Resources

• Improved Atom Efficiency

• Use of Solvent Free or Recyclable Environmentally Benign Solvent systems

Why do we need Green Chemistry ?

• 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.

What it looks for…

• Green chemistry looks at pollution prevention on themolecular scale and is an extremely important area ofChemistry due to the importance of Chemistry in our worldtoday and the implications it can show on our environment.

• The Green Chemistry program supports the invention of moreenvironmentally friendly chemical processes which reduce oreven eliminate the generation of hazardous substances.

• This program works very closely with the twelve principles ofGreen Chemistry.

Green Chemistry is about

Reducing

Waste Materials Hazards Risks Energy Cost

The Principles of Green Chemistry(1-6)

1. It is better to prevent waste than to treat or clean up waste after it is formed.2. Synthetic methods should be designed to maximize the incorporation of all materials used in the process in the final product.3. Wherever practical, synthetic methodologies should be designed to use and generate substances that possess little or no toxicity to human health and the environment.4. Chemical products should be designed to preserve efficacy of function while reducing toxicity.5. The use of auxiliary substances (e.g., solvents, separation agents, etc.) should be made unnecessary whenever possible and innocuous when used.6. Energy requirements should be recognized for their environmental and economic impacts and should be minimized. Synthetic methods should be conducted at ambient temperature and pressure.

The Principles of Green Chemistry(7-12)

7. A raw material feedstock should be renewable rather than depleting whenever technically and ecomonically practical.8. Unnecessary derivatiation (blocking group, protection/de protection, temporary modification of physical/chemical processes) should be avoided whenever possible.9. Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.10. Chemical products should be designed so that at the end of their function they do not persist in the environment and break down into innocuous degradation products.11. Analytical methodologies need to be further developed to allow for real-time in-process monitoring and control prior to the formation of hazardous substances.12. Substances and the form of a substance used in a chemical process should be chosen so as to minimize the potential for chemical accidents, including releases, explosions, and fires.

The uses of auxiliary substances

Separation agents:-1:-Tartaric acid

2.Mandelic acid

3.Camphor sulphonic acidMandelic acid

Camphor sulphonic acid

EG:-solvents , separation agents, etc. should be made unnecessary wherever possible, and innocuous when used”

1.ketone

2.Ester

3.glycols

ketone

ester

glycols

Solvents

Solventless reaction

SUGGESTIONS OFFERED BY GREEN CHEMISTRY :

• It is better to prevent waste than to treat it

• Reduce over consumption of energy

• Reduce waste

• Avoid exploitation of resources

• Reduce the use of auxiliary substances

• Energy required must be recognized for their impact and reduced

• A raw material of feed stock should be renewable rather than depleting where ever technically possible.

EXAMPLES OF GREEN CHEMISTRY

• Safer dry cleaning

• Initially gasoline and kerosene were used

• Supercritical/liquid carbon dioxide (CO2)

• Biodiesel production are use

• Biological conversion of raw material to a product

• Solar energy which is used in space ship , try to apply this energy also in irrigation and also in street light

• Use organic manure/fertilizer instead of inorganic manure/fertilizer by making a peat

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Green Chemistry InChemical Manufacturing

• Create new ways to make desired

materials differentfeedstock, different pathways• Identify desired performance characteristicsand create new materials

Green Chemistry InNon-Chemical Manufacturing

• Identify materials that are unsustainable andphase them out• Identify benign materials that already existand select them• Work with vendors and manufacturers todevelop new benign and environmentallyappropriate materials. Competitive edge!

GREEN CHEMISTRY SUPPORTS SUSTAINABILITY BY:

• Making chemicals safe for our health & environment,

• Using industrial processes that reduce or eliminate hazardous chemicals, &

• Designing more efficient processes that minimize waste

“Energy requirements should be recognized for their environmental impacts and should

be minimized.Synthetic methods should be conducted at

ambientpressure and temperature”

“Although the positive contributions of chemistry and the chemical

industry are many, some pollution problems have also resulted.

Many of these problems can now be solved”.

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The major uses of GREEN CHEMISTRY

Energy

Resource Depletion

Food Supply

Energy

Green Chemistry will be essential in

Developing the alternatives for energy generation (photovoltaics, hydrogen, fuel cells, biobased fuels, etc.) as well as

Continue the path toward energy efficiency with catalysis and product design at the forefront.

Resource Depletion

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

Fossil fuels are a central issue

Food Supply

Green chemistry is developing:

Pesticides which only affect target organisms and degrade to innocuous by-products.

Fertilizers and fertilizer adjuvants that are designed to minimize usage while maximizing effectiveness.

Methods of using agricultural wastes for beneficial and profitable uses.

1. To reduce adverse environmental impact, try appropriate andinnovative choice of material & their chemical transformation.

2. To develop processes based on renewable rather than non-renewableraw materials.

3. To develop processes that are less prone to obnoxious chemicalrelease, fires & explosion.

4. To minimize by-products in chemical transformation by redesignof reactions & reaction sequences . In other words ” Atom economy “

𝐀𝐭𝐨𝐦 𝐄𝐜𝐨𝐧𝐨𝐦𝐲 =𝐌𝐨𝐥.𝐰𝐞𝐢𝐠𝐡𝐭 𝐨𝐟 𝐃𝐞𝐬𝐢𝐫𝐞𝐝 𝒑𝒓𝒐𝒅𝒖𝒄𝒕

𝐌𝐨𝐥.𝐰𝐞𝐢𝐠𝐡𝐭 𝐨𝐟 𝐚𝐥𝐥 𝒓𝒆𝒂𝒄𝒕𝒂𝒏𝒕𝒔× 𝟏𝟎𝟎

5.To develop products that are less toxic.

6. To develop products that degrade more rapidly in the environmentthan the current products.

7. To reduce the requirements for hazardous persistent solvents &extractants in chemical processes.

Goals of Green Chemistry

Significance of green chemistryThe chemical industry releases about 5 billion tons of chemical wastes annually to the environment.it also spends over 300 billion dollars annually for treatment, control and disposal of these chemical wastes . This process formidable challenge for chemists and chemical engineers to review the design , manufacture and use and then to further accomplish and improvement of changes in the design of new products and process

Conclusion

Green chemistry Not a solution to all environmental problems But the most fundamental approach to preventing pollution.

Reference:-

1.Jump up^ "Green & Sustainable Chemistry Network, Japan". Green & Sustainable Chemistry Network. Retrieved 2006-08-042."Chemistry for the Environment". Interuniversity Consortium. Retrieved2007-02-15.3. http://www.rsc.org/suppdata/gc/c0/c0gc00918k/c0gc00918k.pdf

Thank you