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Green Chemistry WorkshopJuly 28, 2009
Sarah Prescott KenickAssistant Professor of Chemistry
University of New Hampshire - Manchester
http://sprescott.wikispaces.com
Green Chemistry
Why do we care?
What is Green Chemistry
12 Principles with examples
What can we do?
What are we doing at UNHM?
How can you learn more/get involved?
Why do we care?
Stories of Early Chemists at work
An early chemist exploring the class of compounds
known as isocyanides, moved his research outdoors
when the overpowering disgusting odor of the
compounds drove him there, then ceased work with
them entirely when the complaints of the neighbors
became too loud
(W.Lietke, Justus Liebigs Annalen de Chemie 1859, 112,316 (quoted in J.A. Green, II &
P.T. Hoffman. “Isonitrile Chemistry,” I.Ugi, Ed,;Academic Press: New York, 1971, p.1.))
The discoverer of mustard gas, a potent blistering agent used as a warfare agent in World War I, reported the terrible effects of his newly prepared compound on the nasal membranes when sniffed. In keeping with sound organic chemical practice of the times, he then tasted his compound! (if you are curious about the outcome, it caused a violent headache, dutifully reported in the manuscript reporting the isolation and analysis of mustard gas)(F.Guthrie, J.Chemical Society 1860, 12,109 (quoted in E.E.Reid, “Organic Chemistry of Bivalent Sulfur,” Vol. 2; Chemical Publishing Co., New York, 1960, pp.238ff))
Release of methyl isocyanate in Bhopal, India killed 3800 people and permanently disabled another 2700
Blue caused by copper contamination - nothing lives - image is a collection basin used as part of remediation (water shunted to treatment plant)
Love Canal - Niagara Falls, NY
Burial site for 21,000 tons chemical waste (1920’s-1950’s)
Heavy rains 1970’s - leaching
1936 - spark ignited floating debris and oil
Annual emissions of dioxins reduced 77% from 1987 - 1995
Sept 19-22,1999
lobsters died in large numbers - due to mosquito pesticides?
What is Green Chemistry?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
The emphasis is on eliminating hazard rather than just preventing exposure Hazard is acknowledged as another important property of matter Green chemistry must be the best chemistry -practical and economically-driven
Resources for the 12 Principles
Anastas and Warner -Green Chemistry Theory and Practice ・Doxsee and Hutchison -Green Organic Chemistry: Strategies, Tools and Laboratory Experiments
Warner, Cannon and Dye- Green Chemistry,Environ. Impact Assessment Review 2004, 24, 775-799.
Presidential Green Chemistry Challenge Awards -Winners and nominations: http://www.epa.gov/greenchemistry/
Real-World Cases in Green Chemistry by Michael C. Cann and Marc E. Connelly....and .ppt presentations (http://academic.scranton.edu/faculty/CANNM1/greenchemistry.html )
12 Principles(Green Chemistry: Theory and Practice, Anastas and Warner, 1998)
#1: Prevent, rather than treat, waste
#2: Maximize use of materials - atom economy
#3: Avoid hazardous materials (reagents, starting materials and solvents) and products or by-products
#4: Design safer products -design in efficacy, design out hazards
#5: Minimize the use of solvents and auxiliary substances
#6: Recognize energy costs and minimize them
#7: Use renewable feedstocks
#8: Omit needless steps -protection/deprotection, e.g.
#9: Use catalysis!
#10: Design products for end of life -products should not persist in the environment, should degrade into innocuous substances
#11: Employ in-line, real-time monitoring/control to avoid generation of hazardous substances in transformations
#12: Whenever possible choose substances that minimize physical danger (explosions, fires, etc.)
#2: Maximize use of materials - atom economy
Production of 2 bottles of ibuprofen generated 3 bottles of waste!
3 bottles of ibuprofen generate less than 1 bottle of waste!
#3: Avoid hazardous materials (reagents, starting materials and solvents) and products or by-products
#4: Design safer products -design in efficacy, design out hazards
#10: Design products for end of life -products should not persistent in the environment, should degrade into innocuous substances
Rohm and Haas Website
#5: Minimize the use of solvents and auxiliary substances
What ideas do you have that would use the principles and practice of green chemistry in your classroom?
What are the connections between the principles and practice of green chemistry and inquiry in the classroom?
What are some benefits of teaching students about green chemistry?
What can we do?
What are we doing at UNHM ?
How can you learn more/get involved?
Green Chemistry in Action at UNHMOrganic Chemistry (traditional)
Hazardous/toxic chemicals as solventsLarge amount of hazardous wasteLittle instruction on alternatives or purpose for use of solvents/chemicalsLittle instruction on real life (outside of generating chemicals/pharmaceuticals) applicationsLittle hands on activity in the classroom (lecture) portion of the course
Green Organic Chemistry course FALL 2007 (active/inquiry/project based)
Little/no hazardous chemicals usedVery low (less than a 500 ml bottle for the class for the semester) hazardous waste Direct in class and lab instruction and activities on the purpose of solvents and alternatives for toxic solventsStudent generated projects on real life applications of content knowledgeGuest speaker, student presentations throughout the semester, and interactive discussion on green and organic chemistry
Examples of Student Assignments - Exam Essays
Each in class exam had a take home essay component around some green chemistry related topic
Exam 1 - alternative solventsStudents given a list of solvents, and asked to devise their own system for ranking relative hazard to human health and the environmentStudents also had to provide alternatives to their top two most hazardous substances on their listMTBE (Methyl tert-butyl ether), Dichloromethane, Benzene, Hexane, Pentane, Methanol, Acetic Acid, Water
Exam 2 - atom economy calculationExam 3 - Is It In Us reflective essay
Examples of student work -PPT presentations
5-10 minute presentations on a green chemistry topic of choice
Students presented throughout the semester - scheduled relative to Organic Chemistry course topicsStudents also produced a poster that was displayed at a Science Symposium at the end of the semester on the same topic
Drug coating using Supercritical CO2
MethodSupercritical CO2 plasticizes polymers
Poly Lactic Acid (PLA)Poly Lactic Glycolic Acid (PLGA)Poly-DL-Lactic Acid (PDLLA)
Drugs are mixed in to liquefied polymers
Creates homogenous mixture
Photo credit: bio-log.co.il
Drug coating using Supercritical CO2Method
Photo credit: bio-log.co.il
Mixture is sprayed in to collection chamber
Produces fibers or particles
Particles containing the polymer/drug mixture are injected under the skin
Gradual release of drug as polymer biodegrades
Benefits to using Supercritical CO2
Drug delivery & coating biopharmaceuticals
Rapid MethodVery efficient
Inexpensive materialWidely availableLow operating costs
Moderate TemperaturesMinimal loss of proteins and growth factors.Moderate temperature and pressure create safer production environments for workers.
Benefits to using Supercritical CO2
Drug delivery & coating biopharmaceuticalsBenign Solvent
Non-toxic to humans.Reduced environmental hazard.Non-flammable.Minimal drug degradation.
Increased dose effectivenessDecreased doses
Increased patient compliance.
More controlled release of the drug.
Reduced side effects.
What’s the difference?? Traditional Paint Low VOC paint
Primary Carrier Oil or solvent based Water or latex based
Resins/Binders Alkyds100 % Acrylics, Polyvinyl
Acetates (PVA)
PigmentsSolvents added in tints
(heavy metals)Less toxic solvents (if
tinted)
Additives Biocides Low Biocides
Application May be difficult Easy
Performance Varies High overall performance
Odor Harsh odor Low or No odor
Dry Time Longer Shorter
Drying/Curing Mechanism
Evaporation, oxidation, polymerization
Evaporation, self coalescing (stable)
Clean-up Mineral Spirits or solvents Warm water and soap
Flashpoint Combustible None
What’s on the market you ask??
Low VOC paint products (Green Seal Certified)Benjamin Moore
Eco Spec latex semi-gloss, flat, eggshell enamel, primerCloverdale Paint
Horizon Interior Line flat, eggshell, semi-gloss, primerSherwin Williams
Harmony Interior Line flat, eggshell, semi-gloss, primerYOLO Colorhouse
Environmentally friendly company (all products zero VOC)Variety of colors offeredFlat, eggshell, semi-gloss
Pros and Cons of Low VOC paints
Benefits ground level ozone pollutionUses less toxic solvents long/short term health effects negative impact on indoor air qualityEqual or better performanceEasy clean-up (no solvents required)Require less ventilation
Hospitals, nursing homes, schools, hotels utilize low-VOC paints
DownsidesLimited colorsAvailabilityCost (of certain products)
100 % acrylics more expensive but best quality
Samples of Student Work - Posters at Symposium
Benefits of “green” teaching
learn how chemistry is “done”, why steps matter (byproducts)
Learn why some chemicals are hazardous, and what the relative risks are (not all chemicals will kill you, and handling measures differ a lot based on what you are working with)
experimental design with an eye to green in the design stage
learn about what real experimentation is like – not just a follow the steps in a lab to a pre-determined conclusion
Labs can be done on the benchtop!
My Projects in progress
August 17-19 2009 - NH Educator Green Chemistry Workshop – for YOU! (handout)http://sprescott.wikispaces.com/Green+Chemistry+Educator+Workshop+2009
3 daysFor NH High School Science EducatorsParticipants will work with student teams this fallSupported by NH Dept. of Ed. LESCN Center Grant
Organic Chemistry Course Fall 09Service learning project (extension of pilot)
Student teams will work with area high school educator to green a high school chemistry lab activity
Green Chemistry INQ444 Course – Spring 09Under DevelopmentWill involve similar service learning/outreach projectsSupported by Inquiry course development funds
My Grand Green Goal
Establish a Green Chemistry Educator Network in the state of New Hampshire and beyond
Provide training for NH (and Mass.) secondary school teachers in both green chemistry and in practice of greening their own labs
extend to middle and elementary teachers once activities are established for these levels
Have my students serving as liaisons with schools and other interested groups to disseminate their work and help others to get “greened”!
AcknowledgementsOrganic Chemistry Students 07-08
Green Chemistry ColleaguesKen Doxsee (University of Oregon)
Jim Hutchison (University of Oregon)
Rich Gurney (Simmons College)
NH Department of EducationLESCN Center
• UNH
Useful Links/Resources• Doxsee and Hutchison -Green Organic Chemistry: Strategies, Tools and
Laboratory Experiments, Brooks Cole, 2003. (lab manual used for some course materials)
• GEMs database (Greener Educational Materials) for Chemists– Many activites, multiple searchable fields, for all levels
– http://greenchem.uoregon.edu/gems.html • EPA - Green Chemistry Presidential Awards
– Lots of industrial examples of green chemistry in action
– http://www.epa.gov/greenchemistry/index.html
• My wiki - http://sprescott.wikispaces.com/ – Up to date information on ongoing projects, both here and collaborations with other
institutions– Today’s presentation– Links to other resources– All our project items, including projects from last year’s summer workshop and fall
course
• Questions?