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China draft Green Chemistry

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General Presentation for our Chinese Visitors at UNIL (Switzerland) …

General Presentation for our Chinese Visitors at UNIL (Switzerland)

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  • 1. The concept of green chemistry 22th April 2010 1 Pierre-Philippe Chappuis, Dr. MSc Contents Introduction What is really green chemistry ? Sustainability metrics Green chemistry definition Twelve principles of green chemistry Green chemistry metrics Major Challenges to Sustainability Conclusion Bibliography 22th April 2010 2 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 2. Introduction (1) 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. 22th April 2010 3 --------------------Pierre-Philippe Chappuis, Dr. MSc Introduction (2) Problems caused by chemical industries 22th April 2010 4 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 3. Introduction (3) Sustainable development and business A way of expressing SD in a business context is in terms of the triple bottom line - economic - society - environment SD "..development that meets the needs of the present without compromising the ability of future generations to meet their own needs" World Commission on the Environment and Development 5 22th April 2010 Pierre-Philippe Chappuis, Dr. MSc Introduction (4) • Sustainability – Ecosystems – Human Heath • Green Engineering – Lifecycle – Systems – Metrics – Thermodynamics • Green Chemistry – Reactions, catalysts – Solvents – Thermodynamics – Toxicology – Metrics Sustainability Green Engineering Green Chemistry « Life cycle assessment and green chemistry : the yin and yang of industrial ecology » P.T. Anastas, Green Chemistry, 2000, 2, 289-295 22th April 2010 6 Pierre-Philippe Chappuis, Dr. MSc
  • 4. What is really green chemistry ? (1) Green chemistry, also called benign chemistry or clean chemistry, is at the heart of Industrial Ecology Adapted from P.T. Anastas & J.J. Breen, J. Cleaner Production, 1997 7 22th April 2010 Pierre-Philippe Chappuis, Dr. MSc What is really green chemistry ? (2) Green Chemistry is the design of chemical products and processes that reduce or eliminate the use and/or generation of hazardous substances. It can be considered as a set of reductions Materials Nonrenewables Cost Reducing Risk & Hazard Energy Waste 22th April 2010 8 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 5. Sustainability metrics (1) Green metrics – What can be measured Mass utilization Material intensity (Mass in product/Mass in raw materials) Atom economy Potential environmental impact Energy utilization Energy intensity (per amount of product) Materials consumed to produce required energy Sustainability metrics Eco-efficiency (Economic indicator/Environmental indicator) Ecological footprint 9 22th April 2010 Pierre-Philippe Chappuis, Dr. MSc Sustainability metrics (2) Materials Pollutant Dispersion Mass of raw material Mass of Product Output Total mass of pollutants released Output Water Consumption Toxics Dispersion Volume of fresh water used Output Total mass of recognized toxics released Output Energy Land Use Net energy used Output Land covered, paved, or in buildings Output Output = Mass of Product, Sales Revenue or Value-added 22th April 2010 10 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 6. Green chemistry definition (1) 22th April 2010 11 --------------------Pierre-Philippe Chappuis, Dr. MSc Green chemistry definition (2) 1. Prevention 2. Atom Economy 3. Less Hazardous Chemical Syntheses 4. Designing Safer Chemicals 5. Safer Solvents and Auxiliaries 6. Design for Energy Efficiency 7. Use of Renewable Feedstocks 8. Reduce Derivatives 9. Catalysis 10. Design for Degradation 11. Real-time Analysis for Pollution Prevention 12. Inherently Safer Chemistry for Accident Prevention Anastas, P.T.; Warner, J. C. Green Chemistry: Theory & Practice, Oxford University Press: New York, 1998. 22th April 2010 12 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 7. Green chemistry definition (3) Prevent wastes Renewable materials Omit derivatization steps Degradable chemical products Use safe synthetic methods Catalytic reagents Temperature, pressure ambient In-process monitoring Very few auxiliary substances E-factor, maximize feed in product Low toxicity of chemical products Yes, it is safe S.L.Y. Tang, R.L. Smith and M. Poliakoff Green Chem, 7, 761-762, 2005 22th April 2010 13 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 1 : waste prevention (1) It is better to prevent waste than to treat or clean up waste after it is formed Chemical Process 22th April 2010 14 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 8. Principle 1 : waste prevention (2) Redesign the Ibuprofen Process Patent 1960 22th April 2010 Patent 1991 15 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 1 : waste prevention (3) Influence of product design on materials flows 22th April 2010 16 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 9. Principle 2 : atom economy (1) Synthetic methods should be designed to maximize the incorporation of all materials used into the final product. J. Andraos, Org. Process Res. Dev., 2006, 10(2), 212-240 22th April 2010 17 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 2 : atom economy (2) Traditional synthesis of ibuprofen (analgesic, anti-inflammatory) 6 stoichiometric steps < 40% atom utilization 22th April 2010 18 Pierre-Philippe Chappuis, Dr. MSc
  • 10. Principle 2 : atom economy (3) Catalytic synthesis of ibuprofen 3 catalytic steps 80% atom utilization (99% with recovered acetic acid) 22th April 2010 19 Pierre-Philippe Chappuis, Dr. MSc Principle 3 : less hazardous chemical syntheses (1) Wherever practicable, synthetic methodologies should be designed to use and generate substances that possess little or no toxicity to human health and the environment. Ecological-chemical footprint RISK = ƒ (Hazard, Exposure) 22th April 2010 20 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 11. Principle 3 : less hazardous chemical syntheses (2) Polycarbonate Synthesis : Phosgene Process Disadvantages phosgene is toxic, corrosive requires large amount of CH2Cl2 polycarbonate contaminated with Cl impurities Polycarbonate Synthesis : Solid-State Process Advantages diphenylcarbonate synthesized without phosgene eliminates use of CH2Cl2 higher-quality polycarbonates 22th April 2010 21 Pierre-Philippe Chappuis, Dr. MSc Principle 4 : designing safer chemicals (1) Chemical products should be designed to preserve efficacity of function while reducing toxicity. Ecological-chemical footprint RISK = ƒ (Hazard, Exposure) 22th April 2010 22 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 12. Principle 4 : designing safer chemicals (2) Cationic electrodeposition coatings containing yttrium provides corrosion resistance to automobiles Replaces lead in electrocoat primers Less toxic than lead and twice as effective on a weight basis 22th April 2010 23 Pierre-Philippe Chappuis, Dr. MSc Principle 5 : safer solvents and auxiliaries (1) The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made unnecessary wherever possible and, innocuous when used. 22th April 2010 24 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 13. Principle 5 : safer solvents and auxiliaries (2) Benign solvents Carbon-carbon bond formation in water Diels-Alder, Barbier-Grignard, pericyclic Reactions in Supercritical Fluids Formation of cyclic ethers Hydrogenation CO2 for Dry Cleaning CO2 (l) Good solvent for small, nonpolar molecules: Hydrocarbons < 20 carbon atoms & some aldehydes, esters, and ketones 22th April 2010 25 Pierre-Philippe Chappuis, Dr. MSc Principle 5 : safer solvents and auxiliaries (3) Supercritical carbon dioxide Physical Properties of CO2 22th April 2010 26 Pierre-Philippe Chappuis, Dr. MSc
  • 14. Principle 6 : design for energy efficiency (1) 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. 27 22th April 2010 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 6 : design for energy efficiency (2) Process Intensification Methods Equipment Reaction e.g. spinning disc reactors microreactors Non-reaction Multifunctional Reactors e.g. compact heat exchanges e.g. reactive distillation Membrane reactors Hybrid separators Alternative Energy sources e.g. microwaves Other methods e.g. membrane adsorption 22th April 2010 28 Pierre-Philippe Chappuis, Dr. MSc
  • 15. Principle 6 : design for energy efficiency (3) Heating Cooling Stirring Distillation Compression Pumping Separation GLOBAL WARMING Energy Requirement (electricity) 22th April 2010 Burn fossil fuel 29 CO2 to atmosphere Pierre-Philippe Chappuis, Dr. MSc Principle 7 : use of renewable feedstocks (1) A raw material of feedstock should be renewable rather than depleting wherever technically and economically practicable. CO 2 Chemical Industry Biorefinery 22th April 2010 30 Consumer Biomass carbohydrates Pierre-Philippe Chappuis, Dr. MSc
  • 16. Principle 7 : use of renewable feedstocks (2) CO2 feedstock in polycarbonate synthesis Conversion of waste biomass to levulinic acid (paper mill sludge, municipal solid waste, unrecyclable waste paper, agricultural residues) Lactic acid as platform molecules (corn starch -> undefined dextrose ->fermentation-> lactic acid -> monomer production -> lactide -> polymer production -> Polylactic acid (PLA) -> polymer modification -> fiber, film, bottle etc.) 31 22th April 2010 Pierre-Philippe Chappuis, Dr. MSc Principle 7 : use of renewable feedstocks (3) Biomass as an alternative feedstock for the chemical industry Petroleum Renewable Non-renewable Biomass Platform molecules Chemical Products 22th April 2010 Plastics 32 Pierre-Philippe Chappuis, Dr. MSc
  • 17. Principle 8 : reduce derivatives (1) Unnecessary derivatization (blocking group, protection/deprotection, temporary modification of physical/chemical processes) should be avoided whenever possible. 22th April 2010 33 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 8 : reduce derivatives (2) Example : synthesis of vitamin B2 (riboflavin) Chemical process Biotechnological process 8 steps chemical process single step fermentation process use of renewable resources 66% less waste water generated Involving dangerous reagents Dangerous waste generated that needs to be incinerated 22th April 2010 no dangerous waste at all 34 Pierre-Philippe Chappuis, Dr. MSc
  • 18. Principle 9 : catalysis (1) Catalytic reagents (as selective as possible) are superior to stoichiometric reagents. 35 22th April 2010 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 9 : catalysis (2) Leading green chemical technology Homogeneous catalysis (eg PTC-Membranes) Biocatalysis (eg immobilized enzymes) Heterogeneous (eg zeolites / mesoporous solids) 22th April 2010 36 Pierre-Philippe Chappuis, Dr. MSc
  • 19. Principle 10 : design for degradation (1) 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. Ecological-chemical footprint RISK = ƒ (Hazard, Exposure) 22th April 2010 37 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 10 : design for degradation (2) Routes of exenobiotic organic chemical introduction into Agricultural systems J.A. Pedersen and al., J. Agric. Food Chem. 2003, 51, 1360-1372 22th April 2010 38 Pierre-Philippe Chappuis, Dr. MSc
  • 20. Principle : 11 real-time analysis for pollution prevention (1) Analytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances. 22th April 2010 39 --------------------Pierre-Philippe Chappuis, Dr. MSc Principle 11 : real-time analysis for pollution prevention (2) An example of new analytical tool for real-time industrial process monitoring and for preventing the formation of toxic materials Electrochemical biosensors : intimate coupling of specific biorecognition events J.Wang, Acc. Chem. Res., 2002, 35(9), 811-816 22th April 2010 40 Pierre-Philippe Chappuis, Dr. MSc
  • 21. Principle 12 : inherently safer chemistry for accident prevention 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. 22th April 2010 41 --------------------Pierre-Philippe Chappuis, Dr. MSc Green chemistry metrics (1) 22th April 2010 42 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 22. Green chemistry metrics (2) E-Factor = Total Waste (kg) / Product (kg) System boundaries ? Process only ? Include water ? Can be sub-divided into organic waste, aqueous waste Useful simple estimate of waste and resource efficiency (the smaller the better) Roger A. Sheldon, Green Chem., 2007, 9, 1273, R. A. Sheldon, « Atom utilisation, E factors and the catalytic solution » C. R. Acad. Sci. Paris, Série IIc (2000) 541 Sector Product [t] E-factor Oil refining 106-108 <0-1 Bulk chemicals 104-106 1-5 Fine chemicals 102-104 5-50+ Pharmaceuticals 10-103 25-100+ 22th April 2010 43 --------------------Pierre-Philippe Chappuis, Dr. MSc Green chemistry metrics (3) 22th April 2010 44 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 23. Green chemistry metrics (4) Metric Name Measures efficiency of Formula Analytical Atom Economy AAE Transformation of reactant atoms into a desired product necessary to prepare the analyte for analysis. Analytical Mass Efficiency AME Chemical and solvent use involved in a chemical reaction. Method Mass Efficiency MME Comprehensive material use necessary for entire analysis method. Energy per Analytical Unit EPAU Energy use for entire analysis method relative to the mass of analyte in sample. 45 22th April 2010 AAE = AME = MME = EPAU = FW of Analyte x 100 FW of Reagents Mass of Analyte(g) x 100 FW of Reagents, Solvents(g) Mass of Analyte (g) x 100 FW of Reagents, Solvents, Cleaning, Prep (g) Total method energy (kJ) x 100 Mass of analyte (g) Pierre-Philippe Chappuis, Dr. MSc Green chemistry metrics (5) for some Common Organic Reactions Reaction Type Yield Atom Economy Environmental Impact Factor assuming 100% yield Nitration 96% 0.93 0.21 Amidation 92% 0.69 4.53 Reduction 100% 0.94 0.06 Methylation 91% 0.63 0.55 Bromination 31% 0.71 0.41 22th April 2010 46 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 24. Green chemistry metrics (6) Ecological metrics Parameters considered •Raw Materials Ecological footprint Ecological advantage Draft Relative environmental impact Energy Consumption 1.00 •Energy consumption Land Use •Land Use •Emissions Emissions 0.50 High 0.00 •Toxicity •Risk potential Product 2 « » Raw Materials Product 3 Toxicity Potential Product 1 Risk Potential Low 22th April 2010 47 --------------------Pierre-Philippe Chappuis, Dr. MSc The major challenges to sustainability (1) Green chemistry Not a solution to all environmental problems. The most fundamental approach to preventing pollution. Recognizes the importance of incremental improvements. 22th April 2010 48 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 25. The major challenges to sustainability (2) Population Energy Global Change Resource Depletion Food Supply Toxics in the Environment Conclusion 22th April 2010 49 --------------------Pierre-Philippe Chappuis, Dr. MSc Population Empirical data shows that increased quality of life correlates with sustainable population control. Increased quality of life, however, has historically resulted in increased damage to the biosphere and the earth’s ability to sustain life. The challenge: How to increase quality of life while minimizing detrimental effects to human health, the environment and the biosphere. The solution: Green chemistry provides a mechanism to addressing this challenge in very real terms. 22th April 2010 50 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 26. Energy (1) The vast majority of the energy generated in the world today is from non-renewable sources that damage the environment. Carbon dioxide Depletion Effects of mining, drilling, etc. Toxics 22th April 2010 51 --------------------Pierre-Philippe Chappuis, Dr. MSc Energy (2) Green Chemistry will be essential in developing the alternatives for energy generation (photovoltaics, hydrogen, fuel cells, biobased fuels, etc.) as well as continuing the path toward energy efficiency with catalysis and product design at the forefront. 22th April 2010 52 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 27. Global change Concerns for climate change, oceanic temperature, stratospheric chemistry and global distillation can be addressed through the development and implementation of green chemistry technologies. For instance : CO2 blowing agent for manufacture of polystyrene foam sheet packaging eliminates 1.6 million kg/year of chlorofluorocarbon blowing agents carbon dioxide obtained from existing by-product commercial and natural sources, no net increase in global CO2 53 22th April 2010 --------------------Pierre-Philippe Chappuis, Dr. MSc Resource depletion Due to the over utilization of non-renewable resources,natural resources are being depleted at an unsustainable rate. Fossil fuels are a central issue. Renewable resources can be made increasingly viable technologically and economically through Green chemistry. Biomass Nanoscience & technology Solar Carbon dioxide Chitin Waste utilization 22th April 2010 54 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 28. Food supply While current food levels are sufficient, distribution is inadequate. Agricultural methods are unsustainable. Future food production intensity is needed.Green chemistry can address many food supply issues. Green chemistry is trying to develop : 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 use 22th April 2010 55 --------------------Pierre-Philippe Chappuis, Dr. MSc Toxics in the Environment Substances that are toxic to humans, the biosphere and all that sustains it, are currently still being released at a cost of life, health and sustainability. One of Green chemistry’s greatest strengths is the ability to design for reduced hazard. 22th April 2010 56 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 29. Perspectives Objectives for Green Chemists around the world Include Green Chemistry principles in the Environment and Education Initiative. Train a new generation of scientists, engineers, and technical works. Account for chemical toxicity and impacts in governmental procurement decisions. Expand world’s pollution prevention program. Strengthen consumer protection enforcement. Empower consumers to make informed choices. Forge strategic partnerships and disseminate information on toxic chemicals and inadequate processes. Apply the TCCR principles : Transparency, Clarity, Consistent and Reasonable. ---------22th April 2010 57 -----------Pierre-Philippe Chappuis, Dr. MSc Conclusion (1) Green chemistry A philosophy, not exactly a scientific discipline. Not a solution to all environmental problems. Cost effective. The most fundamental approach to preventing pollution. A catalyst for sustainable development of the world ! 22th April 2010 58 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 30. Conclusion (2) 22th April 2010 59 --------------------Pierre-Philippe Chappuis, Dr. MSc Bibliography (1) 22th April 2010 60 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 31. Bibliography (2) 22th April 2010 61 --------------------Pierre-Philippe Chappuis, Dr. MSc Bibliography (3) 22th April 2010 62 --------------------Pierre-Philippe Chappuis, Dr. MSc
  • 32. Bibliography (4) 22th April 2010 63 --------------------Pierre-Philippe Chappuis, Dr. MSc Green Chemistry Around the World 22th April 2010 64 Pierre-Philippe Chappuis, Dr. MSc
  • 33. Listen to Nature, Learn from Nature “Being ‘less bad’ is no good.” The world will not evolve past its current state of crisis by using the same thinking that created the situation. -Albert Einstein 22th April 2010 65 --------------------Pierre-Philippe Chappuis, Dr. MSc Thank for your attention ! Questions ? 22th April 2010 66 --------------------Pierre-Philippe Chappuis, Dr. MSc

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