Dr . Ed Marshall Room : M220, RCS 1 e.marshall@imperial.ac.uk www.ch.ic.ac.uk/marshall/4I10 http://webct1.imperial.ac.

1. Imperial College London Module 4I10: Green Chemistry 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

2. Imperial College London Lecture 1: Learning Objectives • 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. "We can't solve problems by using the same kind of thinking we used to create them." Albert Einstein (1879-1955) 4.I10-1-2

3. Imperial College London So what is Green Chemistry? Scenario: 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? 4.I10-1-3

4. Imperial College London Brown Chemistry Is this the public perception of thechemical industry? 4.I10-1-4

5. Imperial College London Brown Chemistry Cuyahoga River 1952 and 1969… …major fires also happened in 1868 and 1936. 4.I10-1-5

6. Imperial College London Brown Chemistry – the UK’s worst chemical accident Flixborough1974 40 tonnes cyclohexane released in 1 minute (225°C, 10 atm) 28 fatalities 4.I10-1-6

7. Imperial College London Brown Chemistry – the world’s worst chemical accident Bhopal 1984 4.I10-1-7

8. Imperial College London Brown Chemistry Is this reputation deserved? 4.I10-1-8

9. Imperial College London Why 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. 4.I10-1-9

10. Imperial College London Class 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: Far more importantly... ...what factors did you consider in your answer? 4.I10-1-10

11. Imperial College London The 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" 4.I10-1-11

12. Disposable Nappies - Simplified System Outline Diagram Environmental Resources timber polymers acrylic acid NaOH packaging pulp and bleaching plastic components super absorbant polymer landfill Other Production Inputs disposable nappy Energy Supply electricity generation recycle retail domestic use landfill incineration Environment (air, land and water)

13. Home Laundered Cotton Nappies - again, simplified Environmental Resources fertiliser cotton cultivation cotton ginning cotton spinning pesticide cotton production and wet processing Other Production Inputs Energy Supply other nappy construction materials packaging cotton nappy detergent manufacture liner manufacture retail sewage treatment electricity generation domestic use packaging disposal water Environment (air, land and water)

14. Imperial College London So what factors do we need to consider? transportation (fuels, emissions) raw materials production process i.e. conditions, risks, hazards waste and the environment solvents other chemicals e.g. additives energy Green Chemistry: a cradle to grave approach 4.I10 1 - 12

15. Imperial College London Green Chemistry: A reductionary approach Green Chemistry reduces… Materials including plant Energy Waste Cost Impact on environment Risk and Hazards Toxicity Green Chemistry is not anti-industry 4.I10 1 - 13

16. Imperial College London Definitions 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 4.I10 1 - 14

17. Imperial College London Summary 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: The reduction or elimination of the use or generation of hazardous substances in the design, manufacture and application of chemical products Green Chemistry ultimately reduces cost and increases responsibility to the environment, the public and shareholders Green Chemistry is a cradle to grave approach 4.I6 1 - 15

18. Imperial College London What 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 4.I6 1 - 16

19. Imperial College London Finally, here is one part of last year’s exam question 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 4.I6 1 - 17