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Green Chemistry

Green Chemistry

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Green Chemistry

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  1. Green Chemistry Teacher Enhancement Workshop Kamehameha High School, Oahu, Hawai’i Presented by Marv Lang, Don Showalter & Gary Shulfer University of Wisconsin-Stevens Point, USA Presentation constructed by Angela Burmeister University of Wisconsin – Stevens Point, USA

  2. What is Green Chemistry? Green chemistry is the use of chemistry for pollution prevention. • Pollution prevention is “the use of materials, processes, or practices that reduce or eliminate the creation of pollutants or wastes at the source. It includes practices that reduce the use of hazardous and nonhazardous materials, energy, water, or other resources as well as those that protect natural resources through efficient use.” -U.S. EPA • The design of chemical products and processes that are more environmentally benign. • Encompasses all aspects and types of processes that reduce negative impacts to human health and the environment. • Focuses on processes and products that reduce or eliminate the use and generation of hazardous substances. • Became a formal focus of the U.S. EPA in 1991 with the formation of their Green Chemistry Program. • Promotes research, development and implementation of inventive chemical technologies that accomplish pollution prevention in both a scientifically-sound and cost-effective manner.

  3. Prevention - It is better to prevent waste than to treat or clean it up after it’s been created. Atom Economy - Synthetic methods should be designed to maximize the incorporation of all the materials that are used in the process. Less Hazardous Chemical Synthesis - Synthetic methods should be designed to use and generate substances that possess little or no toxicity to human health and the environment wherever possible. Designing Safer Chemicals - Chemical products should be designed to effect their desired function while minimizing their toxicity. Safer Solvents and Auxiliaries - The use of solvents, separation agents and other auxiliary substances should be made unnecessary wherever possible and innocuous when used. Design for Energy Efficiency - Energy requirements should be minimized, synthetic methods should be conducted at ambient temperature and pressure. 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 should be minimized or avoided because such steps require additional reagents and can generate waste. 9. Catalysis - Catalytic reagents 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 that 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 their form used in a chemical process should be chosen to minimize the potential for chemical accidents, including releases, explosions and fires. The Twelve Principles

  4. Environmental chemistry is “the study of sources, reactions, transport and fate of chemical entities in the air, water, and soil environments as well as their effects on human health and the environment.” Focuses on the environmental management of chemicals. Concerned not only with the chemical pollutants in the environment but also with the behavior of natural chemicals in natural systems. “When chemical use results in environmental contamination, it is necessary to set standards for acceptable concentrations in water, air, soil and biota.” Has focused on the effects of what man has put into the environment and how to deal with and remediatecontamination sites. “Dilution is the solution to pollution” In contrast, green chemistryfocuses on how to change what human activity puts into the environment in order to eliminate or reduce effects and prevent contamination sites. “An milligram of prevention is worth a kilogram of cure.” Environmental ChemistryversusGreen Chemistry

  5. The Boots Company PLC developed and patented the six step brown synthesis of ibuprofen in the 1960s. The synthesis process results in millions of pounds of unwanted, unutilized, and unrecycled waste chemical byproducts that have to be treated or disposed of each year. The percentage atom economy of the brown synthesis of ibuprofen is 40%60% (by weight) of all reagent atoms are incorporated into unwanted byproduct or waste. The BHC Company developed and patented a greener, three step synthesis of ibuprofen in 1991. Their goal was to develop and put into practice a more efficient and environmentally sensitive method of synthesizing ibuprofen to market. The green synthesis provides for a far greater atom economy at 77% (99% if the acetic acid recovered from the first step is considered). This method prevents the formation of millions of pounds of waste and chemical byproduct as well as saves millions of pounds of reactant materials. The BHC Company won a Presidential Green Chemistry Challenge Award in 1997 for their development of this synthesis. Green Synthesis of Ibuprofen

  6. Green Synthesis of Ibuprofen continued • There are also other environmental advantages to the green synthesis. • The brown synthesis requires auxiliary reagents in stoichiometric amounts. In contrast, the green synthesis is catalytic. • The green synthesis uses reagents which are recovered and reused repeatedly (e.g. HF, Raney nickel, and Pd). • The green synthesis offers greater throughput which allows larger quantities to be produced in less time resulting in less capital expenditure and significant economic benefits.

  7. Benefits to Industry • Economic Benefits of Pollution Prevention: 1) Save money in materials a) Waste is reduced b) More product is produced 2) Improve product quality 3) Conserve energy and water 4) Save money in regulatory and compliance costs a) No liability for waste produced -3M saved $750 million in waste disposal costs by 1995 after implementing their Pollution Prevention Pays (3P) program in 1975. • Pollution Prevention can also help a business: 1) Improve its “bottom line” 2) Make compliance with environmental regulations easier 3) Demonstrate a proactive commitment to the environment

  8. Green Chemistry atThe Dow Chemical Company • Believe in the triple bottom line-meeting social, economic, and environmental objectives. • Committed to reducing emissions by improving energy efficiency, developing less energy-intensive manufacturing processes, and producing climate-friendly products. • Recent efforts and achievements in green chemistry at Dow: • Spinosad- Recipient of the 1999 Presidential Green Chemistry Challenge Award • Active ingredient in Tracer Naturalyte insect control targeting chewing worm pests • Derived through the fermentation of a naturally occurring organism • Helps preserve the local environment while helping to make farms more productive, generate higher yields while still cost-effective to the farmer • Not harmful to beneficial insects, mammals or fish and breaks down quickly into organic matter after three or four hours of sunlight exposure

  9. Dow Chemical Co. continued • Sentricon Termite Colony Elimination System- Recipient of the 2000 PGCC Award • Uses a very small amount of active ingredient and less intrusive than traditional methods • Uses a targeted approach leading to high technical performance, environmental compatibility, and reduced human risk • Protects about 500,000 structures across the country, including the Statue of Liberty, the White House, and Independence Hall, as well as structures in Australia, France, Spain and Japan

  10. Green Chemistry atKodak • Recently set a series of 5-year environmental goals for worldwide operations to be achieved by January 1, 2004. • Address 3 strategic initiatives: • Greater reductions in emissions of 30 priority chemicals, methylene chloride, and carbon dioxide • Preservation of natural resources including reduction in the production of manufacturing waste, energy, water usage, and virtual elimination of heavy metals from Kodak products (e.g. Cd, Hg, Pb, Cr (IV)) • Strengthening of the company’s environmental management

  11. Kodak continued • Pollution Prevention and Waste Minimization • Leader in recycling and reuse of its materials • Captures and reuses manufacturing solvents and silver • Recycles scrap, PET plastic and paper • Silver recovery • Ion exchange technology to recover wastewater silver • T-Grain emulsions use less film and fewer chemicals • EPA 33/50 Program • EPA set goals of 33% reduction by 1992 and 50% reduction by 1995 • Kodak participated and reduced emissions of the 17 targeted chemicals by 71% by the end of 1994

  12. Green Chemistry andEducation • The ACS Division of Education and International Activities, in partnership with the EPA Office of Pollution Prevention and Toxics (OPPT), is currently developing educational materials to start incorporating green chemistry into the general chemistry classroom. • Teachers and professors should begin incorporating green goals into their courses to provide students with knowledge and skills to practice green chemistry without compromising the integrity of the chemical knowledge. • Available resources: • Annotated Bibliography on Green Chemistry- Reference tool for use in chemistry curriculum; available as a searchable data base to the ACS Education Web page at: http://center.acs.org/applications/greenchem • Real-World Cases in Green Chemistry- Contains ten projects that have won or been nominated for the PGCC Award; designed for a variety of undergraduate courses; resource of specific examples of redesigning chemical products and processes. • Chemistry in Context and ChemCom- ACS courses for undergraduate and high school students, respectively, include new green chemistry materials and concepts. • Journal of Chemical Education- Several articles on green chemistry and incorporating it into teaching have been published.

  13. Education continued • Resources in development: • Green chemistry labs, demonstrations, teaching modules for high school teachers, publication of readings, green chemistry video resource for high school teachers, short courses, workshops, meetings and symposia. • Also, undergraduate courses in green chemistry are being developed by various universities such as Carnegie Mellon University, the University of Delaware and the University of Scranton. “The biggest challenge of green chemistry is to get people to adopt it. We would like to see it incorporated into every course from high school onwards.” –A. Matlack, Green Chemistry, February 1999

  14. Resources • Amato, Ivan. The Slow Birth of Green Chemistry. Science,Vol. 259, 12 March 1993, 1538-1541. • Anastas, P.T.; Warner, J.C. Green Chemistry: Theory and Practice; Oxford University Press: New York, 1998. • Cann, Michael C. Bringing State of the Art, Applied, Novel, Green Chemistry to the Classroom by Employing the Presidential Green Chemistry Challenge Awards. J. Chem. Ed.1999, 76 (12), 1639-1641. • Cann, M.C.; Connelly, M.E. Real World Cases in Green Chemistry, American Chemical Society: Washington, DC, 2000. • Collins, T.J. Introducing Green Chemistry in Teaching and Research. J. Chem. Ed.1995, 72 (11), 965-966. • Connell, Des W. Basic Concepts of Environmental Chemistry; CRC Press LLC-Lewis Publishers: New York, 1997. • Dow Chemical Company Web sites. (accessed Mar 2001) www.dow.com/dow_news/corporate/co9_6_28.html; www.dow.com/dow_news/prodbus/20000627a_pb.html;www.dow.com/dow_news/prodbus/20000627b_pb.html; www.dow.com/dow_news/speeches/spe_lauzon_may.html

  15. Resources continued • Freeman, Harry F. Industrial Pollution Prevention Handbook; McGraw-Hill, Inc., 1995. • Frost, John. Green Chemistry at Work: Products Can be Made From Glucose Instead of Benzene. U.S. Environmental Protection Agency Web site. (accessed April 2001) www.epa.gov/docs/epajrnal/fall94/09.txt.html • Kodak Web sites. (accessed Mar 2001) www.kodak/com/US/en/corp/environment/commitment/goals.shtml;www.kodak/com/US/en/corp/environment/operations/prevention/index.shtml; www.kodak/com/US/en/corp/environment/operations/voluntary/design.shtml; www.kodak/com/US/en/corp/environment/operations/voluntary/epa.shtml • Matlack, A. Teaching Green Chemistry. Green Chemistry1999, 1 (1), G19-G20. • Schulz, William. ACS green Chemistry Initiatives Get Boost from EPA Grant. Chemical and Engineering News, August 17, 1998, 47, 59. • U.S. Environmental Protection Agency Web site. (accessed Jan 2001) www.epa.gov/greenchemistry.htm • Again, a special thanks to Angie Burmeister for constructing this presentation!