Download Green Chemistry

Green Chemistry Workshop
July 28, 2009
Sarah Prescott Kenick
Assistant Professor of Chemistry
University of New Hampshire Manchester
[email protected]
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
Sept 19-22,1999
lobsters died in large
numbers - due to mosquito
pesticides?
Annual emissions of
dioxins reduced 77%
from 1987 - 1995
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
UNHM
Green Organic Chemistry
course FALL 2007
Organic Chemistry (traditional)
Hazardous/toxic chemicals as
solvents
Large amount of hazardous
waste
Little instruction on alternatives
or purpose for use of
solvents/chemicals
Little instruction on real life
(outside of generating
chemicals/pharmaceuticals)
applications
Little hands on activity in the
classroom (lecture) portion of
the course
(active/inquiry/project based)
Little/no hazardous chemicals
used
Very 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 solvents
Student generated projects on
real life applications of content
knowledge
Guest 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 solvents
Students given a list of solvents, and asked to devise their own
system for ranking relative hazard to human health and the
environment
Students also had to provide alternatives to their top two most
hazardous substances on their list
MTBE (Methyl tert-butyl ether), Dichloromethane, Benzene,
Hexane, Pentane, Methanol, Acetic Acid, Water
Exam 2 - atom economy calculation
Exam 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
topics
Students 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
Method
Supercritical 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
CO2
Method
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
Photo credit: bio-log.co.il
Benefits to using Supercritical CO2
Drug delivery & coating biopharmaceuticals
Rapid Method
Very efficient
Inexpensive material
Widely available
Low operating costs
Moderate Temperatures
Minimal loss of proteins
and growth factors.
Moderate temperature
and pressure create safer
production environments
for workers.
Benefits to using Supercritical CO2
Drug delivery & coating biopharmaceuticals
Benign Solvent
Non-toxic to humans.
Reduced environmental
hazard.
Non-flammable.
Minimal drug degradation.
Increased dose effectiveness
Decreased doses
Increased patient
compliance.
More controlled release of
the drug.
Reduced side effects.
What’s the difference??
Traditional Paint
Low VOC paint
Oil or solvent based
Water or latex based
Resins/Binders
Alkyds
100 % Acrylics, Polyvinyl
Acetates (PVA)
Pigments
Solvents 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
Primary Carrier
What’s on the market you ask??
Low VOC paint products (Green Seal Certified)
Benjamin Moore
Eco Spec  latex semi-gloss, flat, eggshell enamel, primer
Cloverdale Paint
Horizon Interior Line  flat, eggshell, semi-gloss, primer
Sherwin Williams
Harmony Interior Line flat, eggshell, semi-gloss, primer
YOLO Colorhouse
Environmentally friendly company (all products zero VOC)
Variety of colors offered
Flat, eggshell, semi-gloss
Pros and Cons of Low VOC paints
Benefits
 ground level ozone pollution
Uses less toxic solvents
 long/short term health effects
 negative impact on indoor air
quality
Equal or better performance
Easy clean-up (no solvents
required)
Require less ventilation
Hospitals, nursing homes,
schools, hotels utilize low-VOC
paints
Downsides
Limited colors
Availability
Cost (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+E
ducator+Workshop+2009
3 days
For NH High School Science Educators
Participants will work with student teams this fall
Supported by NH Dept. of Ed. LESCN Center Grant
Organic Chemistry Course Fall 09
Service 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 09
Under Development
Will involve similar service learning/outreach projects
Supported 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”!
Acknowledgements
Organic Chemistry Students 07-08
Green Chemistry Colleagues
Ken Doxsee (University of Oregon)
Jim Hutchison (University of Oregon)
Rich Gurney (Simmons College)
NH Department of Education
LESCN 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?