Lecture 1: An Introduction to Green Chemistry

Dr. Ed Marshall

Room: M220, RCS 1

e.marshall@imperial.ac.uk

www.ch.ic.ac.uk/marshall/4I10

http://webct1.imperial.ac.uk

4.I10 Green Chemistry Lecture 1 Slide 1

Module 4I10: Green Chemistry

Lecture 1:

An Introduction to Green Chemistry

Imperial College

London

Lecture 1: Learning Objectives

By the end of today's lecture you should:

(i) be able to define what is meant by the term Green Chemistry;

(ii) appreciate how Green Chemistry may be beneficial to industry;

(iii)understand that Green Chemistry is not an easy subject.

"We can't solve problems by using the same kind of thinking

we used to create them."

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Albert Einstein (1879-1955)

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So what is Green Chemistry?

Imagine you are at a party and you have to explain what

Green Chemistry is to someone who isn't a chemist.

What would words are you going to use to tell them?

Scenario:

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4.I10-1-3

Imperial College

LondonBrown Chemistry

Is this the public perception

of the chemical industry?

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Brown Chemistry Imperial College

London

Cuyahoga River

1952 and 1969…

…major fires also happened

in 1868 and 1936.

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Brown Chemistry

Flixborough 1974

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London

40 tonnes cyclohexane released

in 1 minute (225 °C, 10 atm)

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Brown Chemistry – the UK’s worst chemical accident

Brown Chemistry Imperial College

London

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4th December 2004

Brown Chemistry – the world’s worst chemical accident

Brown Chemistry

Is this reputation

deserved?

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Imperial College

LondonWhy does the chemical industry need Green Chemistry?

The Chemical Industry has responsibilities:

to the environment

to the public

to shareholders

As legislation becomes stricter and as petrochemical feedstocks are

depleted, so green chemical processes will become more cost effective.

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Imperial College

LondonClass exercise: Which is greener - Disposable or Cotton Nappies?

In groups of 4, discuss whether it is better to use disposable nappies

(diapers) or reusable cotton nappies.

Results of Vote:

In favour of disposable:

In favour of cotton:

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Imperial College

LondonThe answer

In 2004 the UK Environment Agency concluded that there is…

"no significant difference between the environmental impacts

of either nappy system, although the life cycle stages are different"

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Imperial College

LondonSo what factors do we need to consider?

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transportation

(fuels, emissions)

waste and the

environment

energy

Green Chemistry: a cradle to grave approach

production

process

i.e. conditions,

risks, hazards

raw materials

solvents

other chemicals

e.g. additives

Imperial College

LondonGreen Chemistry: A reductionary approach

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Green Chemistry reduces…

Green Chemistry is

not anti-industry

Imperial College

LondonDefinitions of Green Chemistry

“The reduction or elimination of the use or generation of hazardous

substances in the design, manufacture and application of chemical

products”

Green Chemistry theory and Practice - Anastas and Warner

“Green Chemistry underlies our commitment to potentially harmful

technologies by developing alternative syntheses to prevent

environmental pollution.”

Green Chemistry is not anti-industry

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Imperial College

LondonSummary of Lecture 1

By the end of today's lecture you should:

• be able to define what is meant by the term Green Chemistry:

• appreciate how Green Chemistry may be beneficial to industry:

• understand that Green Chemistry is not an easy subject:

Green Chemistry ultimately reduces cost and increases

responsibility to the environment, the public and shareholders

The reduction or elimination of the use or generation of

hazardous substances in the design, manufacture and

application of chemical products

Green Chemistry is a cradle to grave approach

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Imperial College

LondonWhat we will cover in lectures 2-8

Lecture 2: Metrics

Lecture 3: Catalysis

Lecture 4: Green Solvents

Lecture 5: Biofuels

Lecture 6: Biomass

Lecture 7: Biotechnology

Lecture 8: Hazards

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Imperial College

LondonFinally, here is one part of last year’s exam question

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Green Chemistry is often said to be a 'cradle to grave' approach. Explain

what this term means with specific reference to the industrial production

of polyethylene.5 marks