1. GREEN CHEMISTRY 2010/2011

2. background… Taken in large part from Paul L. Bishop’s Pollution Prevention – Fundamentals & Practice, Chapter 9.

3. problems caused by chemical industry Inside the plantExposure of employees to carcinogenic substances and toxics Pollution exiting the plantAir emissionsFugitive emissions from storage tanks Smokestacks emissions Evaporating solvents Water pollutionIncompletely treated wastewater Liquid leaks and groundwater contamination Solid wasteSludge from wastewater treatment Heavy metals

4. problems continue… Impacts of using the chemical product FertilizersEutrophication or nearby water bodies Herbicides & pesticidesResidues in food Groundwater contamination Chlorofluorocarbons (CFCs) Stratospheric ozone holes → skin cancer GasolineUrban air pollution MTBE fuel additiveGroundwater pollution Impacts after useFlame-retardant chemicalsLandfill hazard Paint pigmentsHeavy metals in soil

5. The E factor…

6. is the actual amount of waste produced in the process, defined as everything but the desired product, except: water. A higher E factor means more waste and, consequently, greater negative environmental impact. The ideal E factor is zero. The E factor…definition

7. green chemistry…definition 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 Theory & Practice, P T Anastas & J C Warner, Oxford University Press 1998

8. 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 green chemistry…is about

9. The 12 principles ….

10. 7 Use of Renewable Feedstocks –A raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable. 8 Reduce Derivatives –Unnecessary derivatization (use of blocking groups, protection/de-protection, and temporary modification of physical/chemical processes) should be minimised or avoided if possible, because such steps require additional reagents and can generate waste. 9 Catalysis –Catalytic reagents (as selective as possible) are superior to stoichiometric reagents. 10 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. 11 Real-time Analysis for Pollution Prevention –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 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. Still … the 12 principles ….

11. “It is better to prevent waste than to treat or clean up waste after it is formed”

12. “The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made unnecessary wherever possible, and innocuous when used”

13. “Energy requirements should be recognized for their environmental impacts and should be minimized. Synthetic methods should be conducted at ambient pressure and temperature”

14. “A raw material of feedstock should be renewable rather than depleting wherever technically and economically practical”

15. A series of reductions …. WASTES RISK & HAZARD REDUCING COSTS MATERIALS ENERGY NON - RENEWABLES

17. Industrial Ecology Goals for Green Chemistry Adopt a life-cycle perspective regarding chemical products and processes. Realize that the activities of your suppliers and customers determine, in part, the greenness of your product. For non-dissipative products, consider recyclability. For dissipative products (e.g. pharmaceuticals, crop protection chemicals) consider the environmental impact of product delivery Perform green process design as well as green product design

18. development that meet the needs of the present without compromising the ability of the future generation to meet their own needs. Sustainable development is…

19. The Clean Technology Pool….

20. Catalysis….

21. Plastics….

22. Biodegradable materials….

24. Fossil oil products are totally dominating as fuel, that is energy carrier, for many purposes especially transport. Alternatives now on the market include ethanol and biogas. In the long term hydrogen appears to be an even more interesting alternative energy carrier, as it may be used in fuel cells. Hydrogen and Fuel Cells vs Fossil Fuels and Combustion

25. Application of GC in industry….