Green chemistry and its role for sustainability

Green Chemistry and its Role for Sustainability As A branched topic of the UNESCO conference on ESD Bonn, Germany, 2009 Presenter: Dr.. Learning 0bjectives To conceptualize the sustaina

Green Chemistry and its Role for

Sustainability

As

A branched topic of the UNESCO conference

on ESD Bonn, Germany, 2009

Presenter: Dr Zeinab Shaaban Abu-Elnaga

Faculty of Science Mansoura University

Egypt

Learning 0bjectives

To conceptualize the sustainability and ESD

To understand how to apply this concept in our research fields of interest aiming to safe our plant

To think prospectively about how to change our education subjects to be sustainable learning tools by Investigating examples of green chemistry applications relevant to students

To understand the important role of the green chemistry and how to deal with it in our practical life

The topic is very vast but I have tried to cover it in one

lecture and I will give the links for more details of

zenab_77@mans.edu.eg

Performance Objectives:

To understand the importance of Green chemistry for sustainability

To design and interpret greener route to the traditional chemical reactions

To learn how to teach green chemistry as a lab course

• Meeting the needs of the present generation without compromising the needs of future generations

• Green chemistry: technologies of the invention, design and application of chemical products and processes to reduce or to eliminate the use and generation of hazardous substances ,and where possible utilize renewable raw materials

Primary pollution prevention not remediation

Use of chemistry for improved environmental performance

Is the goal

is the means

zenab_77@mans.edu.eg

As human beings - we are part of the environment

The way in which we interact with our environment influences the quality of our lives

Green Chemistry

A tool

Industrial ecology

Sustainable

development

the goal

Green chemistry, lies at the heart of the industrial ecology

Green chemistry, is called also Benign chemistry or clean chemistry for sustainability

• Refers to the field of chemistry dealing with

1- Synthesis (the path to making chemicals)

2- Processing (the actual making of chemicals)

3- Use of chemicals that reduce risks to humans and impact on the environment

Green chemistry education: A key to sustain the development of new educational materials

Green Chemistry Is About

Cost

Waste Materials Hazard Risk

Energy

Principles of Green Chemistry

Prevent waste.

Design safer chemicals and products.

Design less hazardous chemical syntheses.

Use renewable feed stocks.

Use catalysts, not stoichiometric reagents: Catalysts are used in small amounts and

can carry out a single reaction many times They are preferable to stoichiometric reagents, which are used in excess and work only once.

Avoid chemical derivatives: Avoid using blocking or protecting groups or any

temporary modifications if possible generate waste.

Maximize atom economy.

Use safer solvents and reaction conditions

Increase energy efficiency.

Design chemicals and products to degrade after use.

Analyze in real time to prevent pollution.

Minimize the potential for accidents.

Originally published by Paul Anastas and John Warner in Green Chemistry: Theory

and Practice (Oxford University Press: New York, 1998). 2009

zenab_77@mans.edu.eg

Now, how can we deal with green chemistry

at our practical life

Just we need to change our mind set and applying the concept in

Classrooms laboratory manufacture And finally the surrounding environment

O 3 or supercritical water oxidation

• If the chemical reaction of the type

• A + B P + W

• Find alternate A or B to avoid W

• Example 1:

• Disinfection of water by chlorination Chlorine oxidizes the pathogens there by killing them, but at the same time forms harmful chlorinated compounds.

• A remedy is to use another oxidant, such as

2009 zenab_77@mans.edu.eg

Example 2 of green chemistry

• Production of allyl alcohol CH2=CHCH2OH

• Traditional route: Alkaline hydrolysis of allyl chloride, which generates the product and hydrochloric acid as a by-product

• Greener route, to avoid chlorine: Two-step using propylene

(CH2=CHCH3), acetic acid (CH3COOH) and oxygen (O2)

• Added benefit: The acetic acid produced in the 2nd reaction can be recovered and used again for the 1st reaction, leaving

CH2=CHCH2Cl + H2O CH2=CHCH2OH + HCl

CH2=CHCH2OCOCH3 + H2O CH2=CHCH2OH + CH3COOH

CH2=CHCH3 + CH3COOH + 1/2 O2 CH2=CHCH2OCOCH3 + H2O

Example 3 of green chemistry

• Production of styrene (=benzene ring with CH=CH2 tail)

• Traditional route: Two-step method starting with benzene,

which is carcinogenic) and ethylene to form ethylbenzene, followed by dehydrogenation to obtain styrene

• Greener route: To avoid benzene, start with xylene (cheapest

source of aromatics and environmentally safer than benzene)

• Another option, still under development, is to start with

toluene (benzene ring with CH3 tail)

+ H2C=CH2 catayst

CH2CH3

ethylbenzene catayst

CH=CH2

CH2-CH3

ethylbenzene

styrene

2009 zenab_77@mans.edu.eg

Green chemistry education

Chemistry students need to be encouraged to consider the principles of green chemistry when designing processes and choosing reagents

Interactive Teaching Units (ITU) have been developed specifically to introduce undergraduate students to green chemistry

There are numerous scholarships and grants available for researchers and young scholars who are furthering the goals of green chemistry

Green Chemistry:

Preventing Pollution Sustaining the Earth

Green chemistry has come a long way since its birth in 1991, growing from a small grassroots idea into a new approach to scientifically-based environmental protection

All over the world, governments and industries are working with “green” chemists to transform the economy into a sustainable enterprise

Who knows? Green chemistry may be the next social

movement that will set aside all the world’s differences and allow for the creation of an environmentally commendable

zenab_77@mans.edu.eg

References

http://www.epa.gov/greenchemistry/

http://www.epa.gov/greenchemistry/pubs/educat.html

http://www.epa.gov/greenchemistry/

http://www.epa.gov/greenchemistry/pubs/principles.html

http://en.wikipedia.org/wiki/Green_chemistry

http://portal.acs.org/portal/acs/corg/content?_nfpb=true&_pageLabel=PP_TRANSITIO NMAIN&node_id=830&use_sec=false&sec_url_var=region1& uuid=76247a16-94d0-458e-9092-10de1c35f2c6

http://books.google.com/books?id=ZMjkTMwO3NkC&dq=green+chemistry&printsec=fr ontcover&source=bl&ots=ZdGD63CxOJ&sig=vM94PxekSEhIX3a9yFOPpDAOXGo&hl

=en&ei=mD9RSqSoDqDMjAfJg4mfBQ&sa=X&oi=book_result&ct=result&resnum=8 http://books.google.com/books?id=ZMjkTMwO3NkC&dq=green+chemistry&printsec=fr ontcover&source=bl&ots=ZdGD63CxOJ&sig=vM94PxekSEhIX3a9yFOPpDAOXGo&hl

=en&ei=mD9RSqSoDqDMjAfJg4mfBQ&sa=X&oi=book_result&ct=result&resnum=8