The principles of green chemistry focus on avoiding the creation of dangerous substances.newphotoservice/Getty Images/iStockphoto
When his two-year-old son died, a question haunted Dr. John Warner. A senior research scientist at Polaroid Corp., he wondered if something he handled in the lab might have caused the birth defect that killed his son.
That question led Dr. Warner to help create a new field of chemistry – green or sustainable chemistry, the first Canadian conference on which was recently held at Queen's University in Kingston, Ont.
Dr. Warner was a very successful chemist by the mid-1990s, but his son's death led him to the disturbing realization that he had never had a course in toxicology and knew little about what makes some chemicals hazardous. Neither do most chemists, he says.
Even today, Dr. Warner says, no university in the world requires a course in toxicology to obtain a chemistry degree. "Isn't that kind of weird?" he asked in his keynote address at the inaugural Sustainable Chemistry Summit.
So Dr. Warner left the private sector to teach at the University of Massachusetts, where he helped introduce green chemistry to the curriculum. With Dr. Paul Anastas, he co-wrote Green Chemistry: Theory and Practice, generally considered the field's defining book. It contains the 12 principles of green chemistry, a sort of how-to guide for environmentally friendlier chemistry.
Traditionally, chemists accepted that they worked with dangerous substances, relying on masks and other protective gear. For many years, the industry paid little attention to the risks. More recently, that attitude gave way to containing or cleaning up the mess with scrubbers and filters.
Green chemistry holds that instead of containing or cleaning up messes, it's better to avoid them.
That means using harmless rather than toxic materials whenever possible, and designing processes that waste less, minimize energy requirements and use renewable materials. Often it means replacing petroleum-based materials with those made from plants, water, carbon dioxide and other common, relatively harmless substances.
Green chemistry isn't an absolute term. "If it's doing less damage than what's currently being done," says Dr. Philip Jessop, Canada research chair in green chemistry at Queen's. "It's green – for now."
Dr. Jessop has developed a "switchable" solvent that combines with substances like oil and paint in the presence of carbon dioxide. When the carbon dioxide is removed, it separates from the materials again. This environmentally friendly solvent can be used instead of energy-intensive distillation for recycling plastics and extracting bitumen from oil sands, among other things.
A spinoff company called Switchable Solutions Inc. has been created to commercialize the technology.
The company is one of the first fruits of GreenCentre Canada. Created at Queen's in 2009 to bring together academe's green chemists and industry, GreenCentre is, according to executive director Dr. Rui Resendes, "arguably the world's only green chemistry commercialization centre." Dr. Jessop is the centre's technical director.
Speakers at the Sustainable Chemistry Summit stressed that commercialization is important. "A technology that doesn't make it to the market doesn't help the environment," Dr. Jessop says. They also argued greener processes needn't mean sacrificing profits or jobs.
"It's not a philosophy. It's not a social movement. It's a science," says Dr. Warner. To prove green chemistry can be good business, he founded the Warner Babcock Institute for Green Chemistry LLC. The Wilmington, Mass., company solves real-world problems for business customers using green chemistry. Four years old, it has more than 200 patents and is profitable, Dr. Warner says – "tell me green chemistry isn't the right thing to do."
Dr. Anastas and Dr. Warner's first principle of green chemistry is: "It is better to prevent waste than to treat or clean up waste after it is formed." The second principle is about designing processes so as much raw material as possible ends up in the finished product. In business, that's called efficiency.
Other green chemistry principles focus on avoiding the creation of dangerous substances – which, green chemistry advocates point out, can be costly to contain or clean up, and create risks for the businesses that deal with them.
Those risks can be huge, as in the explosion at Union Carbide Corp.'s plant in Bhopal, India, in 1984 that killed thousands, injured or sickened thousands more and mired Union Carbide in years of lawsuits.
CO2 Solution Inc., of Quebec City, has adapted an enzyme found in the human body to help remove carbon dioxide from industrial gases. Not only does it allow the use of a less toxic solvent than that which is commonly used, but Jonathan Carley, CO2's vice-president of business development, says it needs 30 per cent less energy and doesn't require as tall an enclosure.
The company has 23 patents and is working with major companies to commercialize the product, Mr. Carley says.
Woodbridge Group, a Mississauga, Ont., auto parts manufacturer, is using bio-polyol from vegetable oils to replace petroleum-based oils in making car seat cushions. The company makes cushions with 7 per cent bio-polyol today and is aiming for 30 to 50 per cent, says Dr. Hamdy Khalil, global research director.
Dr. Emily Cranston, assistant professor at McMaster University, is working with nanocellulose, which she says could be used to reinforce plastics. Nanocellulose comes from wood, and would replace materials that come from non-renewable sources and are hard to recycle.
Dr. Audrey Moores, assistant professor at McGill University, is studying the use of nanocrystalline cellulose – one type of nanocellulose – in catalytic reactions.
Their work could have real-world impact soon. CelluForce, backed by Domtar Corp. and FPInnovations, a non-profit forest industry research group, plans to open a plant producing nanocrystalline cellulose in Windsor, Que., early in 2012.
While green chemistry is already having a real impact, green chemists say teaching young chemistry students to think in new ways may be their most important task. In the end, Dr. Warner says, "it's going to be the people who make the chemicals who change."