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GREENING THE CHEMISTRY CURRICULUM. Michael Cann, Chemistry Department http://academic.scranton.edu/faculty/CANNM1/greenchemistry.html. Sustainability. "Meeting the needs of the present without compromising the ability of future generations to meet their needs."
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GREENING THE CHEMISTRY CURRICULUM Michael Cann, Chemistry Department http://academic.scranton.edu/faculty/CANNM1/greenchemistry.html
Sustainability • "Meeting the needs of the present without compromising the ability of future generations to meet their needs." (The U.N. Brundtland Commission 1987) JUSTICE? Michael C. Cann, University of Scranton
Sustainability? Nature • Are we exceeding the carrying capacity of the earth? Are we using resources and creating waste faster that the earth can take our wastes and convert them back into resources? Resources Consumption Waste Humans Resources Consumption Waste Michael C. Cann, University of Scranton
Chemists Must Place a Major Focus on the Environmental Consequences of Chemical Products and the Processes by which these Products are Made. We must consider our chemical ecological footprint.
GREEN CHEMISTRY • Green Chemistry, or sustainable/environmentally benign chemistry is the design of chemical products and processes that reduce of eliminate the use and generation of hazardous substances • Minimize: • waste • energy use • resource use (maximize efficiency) • utilize renewable resources Michael C. Cann, University of Scranton
The Twelve Principles of GREEN CHEMISTRY(Anastas and Warner 1998) 1.It is better to prevent waste than to treat or clean up waste after it is formed. 2. Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product. 3. Wherever practicable, synthetic methodologies should be designed to use and generatesubstances that possess little or no toxicity to human health and the environment. 4. Chemical products should be designed to preserve efficacy of function while reducing toxicity. 5. The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made unnecessary whenever possible and, innocuous when used. 6. Energy requirements should recognized for their environmental and economic impacts and should be minimized. Synthetic methods should be conducted at ambient temperature and pressure. Michael C. Cann, University of Scranton
The Twelve Principles of GREEN CHEMISTRY (Anastas and Warner 1998) 7.A raw material feedstock should be renewable rather than depleting whenever technically and economically practical. 8. Unnecessary derivatization (blocking group, protection/deprotection, temporary modification of physical/chemical processes) should be avoided whenever possible. 9. Catalytic reagents (as selective as possible) are superior to stoichiometric reagents. 10. 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. 11. 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. Substances and the form of a substance used in a chemical process should chosen so as to minimize the potential for chemical accidents, including releases, explosions, and fires. Michael C. Cann, University of Scranton
GREEN CHEMISTRY • Pollution Prevention Act 1990 • GC Began in 1991 at EPA, Paul Anastas • 1996 Presidential Green Chemistry Challenge Awards • 1997 Green Chemistry and Engineering Conference • 1999 Journal “Green Chemistry” • Chemical and Engineering News • 2000 GCI integrated into ACS • 2000 Journal of Chemical Education Michael C. Cann, University of Scranton
Examples of Green Chemistry Presidential Green Chemistry Challenge Award Winners For more informational on Presidential Green Chemistry Challenge Award Winners: http://www.epa.gov/greenchemistry/presgcc.html • New syntheses of Ibuprofen and Zoloft. • Integrated circuit production. • Removing Arsenic and Chromate from pressure treated wood. • Many new pesticides. • New oxidants for bleaching paper and disinfecting water. • Getting the lead out of automobile paints. • Recyclable carpeting. • Replacing VOCs and chlorinated solvents. • Biodegradable polymers from renewable resources. Michael C. Cann, University of Scranton
GREEN CHEMISTRY • "Green chemistry represents the pillars that hold up our sustainable future. It is imperative to teach the value of green chemistry to tomorrow's chemists." • Daryle Busch, President ACS, June 26, 2000, “Color Me Green” • Chem. Eng. News 2000, 78 (28) 49-55. Michael C. Cann, University of Scranton
ENVIRONMENTAL CHEMISTRY • Poster/Oral Presentation on one of the PGCCAward Winning Proposals 1996 • Cann, Michael C., J. Chem. Ed.1999, 76 (12), 1639-1641. Michael C. Cann, University of Scranton
REAL-WORLD CASES IN GREEN CHEMISTRY • ACS/EPA Green Chemistry Educational Materials Development Project, 1998 • Compilation of materials on real-world green chemistry (based on PGCC) in a format that can be used for educational purposes • Each case acts as an informational resource for instructors to use in greening their courses • Marc Connelly • http://www.acs.org/portal/Chemistry?PID=acsdisplay.html • &DOC=education\greenchem\cases.html Michael C. Cann, University of Scranton
MAINSTREAMING GREEN CHEMISTRY • Insertion of green chemistry into mainstream chemistry courses • Need faculty who teach these courses to develop modules on green chemistry related to topics already covered in their course • Make it easy (lower Eact) for other • faculty to do the same; • place materials on the web Michael C. Cann, University of Scranton
WEB BASED GREEN CHEMISTRY MODULES FOR SPECIFIC CHEMISTRY COURSES • Major support-The Camille and Henry Dreyfus Foundation • Additional support-ACS/EPA, University of Scranton • T. Dickneider, T. Foley, D. Marx, D. Narsavage-Heald, J. Wasilewski • (The “Green Machine”) Michael C. Cann, University of Scranton
GREEN CHEMISTRY MODULES FOR SPECIFIC CHEMISTRY COURSES • General -Surfactants for CO2 • Organic -Atom economy • Inorganic –Activators of hydrogen peroxide for green oxidation • Biochemistry –Confirm, Mach 2 and Intrepid pesticides • Advanced Organic –Elimination of Chlorine in NAS Michael C. Cann, University of Scranton
GREEN CHEMISTRY MODULES FOR SPECIFIC CHEMISTRY COURSES • Polymer –Polyaspartic acid • Industrial –Petretec polyester regeneration • Environmental –Sea-nine antifoulant • Toxicology –Confirm, • Mach 2, and Intrepid Michael C. Cann, University of Scranton
GREEN CHEMISTRY MODULES FOR SPECIFIC CHEMISTRY COURSES • Introduction to Green Chemistry 17,000 hits; 500 different universities • Module: text, questions and bibliography • Notes to instructors • Power Point presentation • http://academic.scranton.edu/faculty/CANNM1/dreyfusmodules.html Michael C. Cann, University of Scranton
ATOM ECONOMYBarry Trost, Stanford University“Because an Atom is a Terrible Thing to Waste” • How many of the atoms of the reactant are incorporated into the final product and how many are wasted? Infusing green chemistry into organic. Michael C. Cann, University of Scranton
ATOM ECONOMY Atom Economy Table % Atom Economy = (FW of atoms utilized/FW of all reactants) X 100 = (137/275) X 100 = 50% Michael C. Cann, University of Scranton
ATOM ECONOMY IN THE WITTIG REACTION Michael C. Cann, University of Scranton
GREEN CHEMISTRY • The Synthesis of Ibuprofen • Advil, Motrin, Medipren • 28-35 million pounds of ibuprofen are produced each year (37-46 million pounds of waste) Michael C. Cann, University of Scranton
Environmental Advantages of BHC Synthesis of Ibuprofen • Less waste • greater atom economy • catalytic versus stoichiometric reagents • recycling, reuse, recovery of byproducts and reagents (acetic acid >99%; HF >99.9%) • greater throughput (three steps versus five steps) and overall yield (virtually quantitative) • Fewer auxiliary substances (solvents separation agents) Michael C. Cann, University of Scranton
Economic Advantages of BHC Synthesis of Ibuprofen • Greater throughput and overall yield (three steps versus five steps) • Greater atom economy (uses less feedstocks) • Fewer auxiliary substances (solvents separation agents) • Less waste (lower disposal costs) Michael C. Cann, University of Scranton
GREEN CHEMISTRY • Major Focus: Replacement of organic solvents -VOCs, halogenated, almost 15 billion kilograms produced wordwide each year • Solvent free • Solvent alternatives: • Ionic liquids • Fluorous • Carbon dioxide Michael C. Cann, University of Scranton
GREEN CHEMISTRY • Dry Cleaning • Initially gasoline and kerosene were used • Chlorinated solvents are now used, such as perc • Supercritical/liquid carbon dioxide (CO2); infusing green chemistry into general chemistry Michael C. Cann, University of Scranton
Solubility of Substances in CO2 • Carbon dioxide a non polar molecule since the dipoles of the two bonds cancel one another. • Carbon dioxide will dissolve smaller non polar molecules • hydrocarbons having less than 20 carbon atoms • other organic molecules such as aldehydes, esters, and ketones • But it will not dissolve larger molecules such as oils, waxes, grease, polymers, and proteins, or polar molecules. Michael C. Cann, University of Scranton
Surfactant Michael C. Cann, University of Scranton
CO2 Surfactant:Joe DeSimone, UNC, NCSU, NSF Science and Technology Center for Environmentally Responsible Solvents and Processes, PGCC Award 1997
CO2 Surfactant Michael C. Cann, University of Scranton
http://www.hangersdrycleaners.com/ Michael C. Cann, University of Scranton
Environmental/Economic Advantages of Liquid CO2 • Using CO2 eliminates hazardous waste generation of perc. • CO2 does not pose the environmental and human health risks associated with perc (used by 34,000 dry cleaners in US). • Using CO2 reduces environmental regulatory burdens for Hangers operators. • Uses waste CO2 from other processes. Michael C. Cann, University of Scranton
GREEN CHEMISTRY • Antifoulants (algae and seaweed; • barnacles and diatoms) • Pesticides, infusing green • chemistry into environmental chemistry Michael C. Cann, University of Scranton
Antifoulants • TBTO • Half-life of TBTO in seawater is > 6 months • Bioconcentration, 104 • Chronic Toxicity • Thickness of oyster shells • Sex changes in whelks • Imposex in snails • Immune system in dolphins and others? Michael C. Cann, University of Scranton
Antifoulants • DCOI (PGCC award; Rohm and Haas) • Acutely toxic to a wide range of marine organisms (effective anitfoulant) • Rapid biodegradation to nontoxic products (½ life < 1 hour) • Low Bioconcnetration (bioconcentration =13) • Environmental Conc. < Acute Toxicity level • No Chronic Toxicity • Rapid partitioning to the sediment (low bioavailability) 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one Michael C. Cann, University of Scranton
Green Chemistry–Environmental Chemistry • Ozone hole and troposheric air pollution: carbon dioxide as a replacement for CFCs and hydrocarbon blowing agents; surfactants for carbon dioxide so that carbon dioxide can be used to replace VOCs. • Pesticides: readily biodegradable marine antifoulant as replacement for tributyltin oxide; selective pesticides as replacements for broad spectrum pesticides. • Toxic organic chemicals (e.g. dioxins): activators of hydrogen peroxide to replace chlorine bleaching agents. • Polluted water and sewage treatment: biodegradable scale inhibitors and dispersing agents as a replacement for polyacrylate polymer. • Solid waste, landfills and closed loop recycling: Petretec process for conversion of PET back into its monomers and reformation into virgin PET. Michael C. Cann, University of Scranton
Environmental ChemistryBaird & Cann • Introduction to Green Chemistry –Atom economy; synthesis of ibuprofen. • Ozone –CO2 as a blowing agent; Harpin as a replacement for methyl bromide fumigant. • Tropospheric pollutants –CO2 surfactants. • Greenhouse gases –scCO2 in photolithography. • Energy/petroleum –biodegradable polymers from renewable resources. • Pesticides –selective pesticides; termite control/ reduced risk pesticides. Michael C. Cann, University of Scranton
Environmental ChemistryBaird & Cann • Toxic organics –non-chlorine bleaching agents, H2O2 activators • Water pollution/purification –enzymatic preparation of cotton textiles; biodegradable chelating agents • Heavy metals –removal of lead from automobile paint; removal of arsenic and cadmium from pressure treated wood • Solid waste –biodegradable antiscalant; recylable carpeting Michael C. Cann, University of Scranton
Green Chemistry Endeavorsat Scranton • “Greening” existing chemistry textbooks. • “Organic Chemistry, Solomons & Fryhle, Wiley • “Chemistry Foundations and Applications,” Macmillan • Translation of our web-based Green Chemistry Modules into Spanish & Portuguese. • The business side of green chemistry. • Infusion into business courses • Bringing green chemistry to the high school and secondary school level. • Integrating sustainability throughout our campus http://matrix.scranton.edu/sustainability/default.shtml Michael C. Cann, University of Scranton
Acknowledgements • Marc Connelly • The “Green Machine:” Trudy Dickneider, Tim Foley, David Marx, Donna Narsavage-Heald, Joan Wasilewski • Camille and Henry Dreyfus Foundation • American Chemical Society: Sylvia Ware, Mary Kirchhoff, Janet Boese, Mary Ann Ryan • Environmental Protection Agency: Tracy Williamson • Green Chemistry Institute: Paul Anastas • Universidad de Las Palmas de Gran Canaria, Maria de la Concepcion, Sebastian Perez • Universidade Federal de Pelotas (UFPel)Eder J. Lenardãoa & Colleagues Michael C. Cann, University of Scranton