A U.S. chemist demonstrates a catalyst converter that reduces chemical emissions from diesel engines.
Crédito: Laboratorios Argonne
Scientists Set Sights on \'Green\' Chemistry
Por Stephen Leahy
New technologies are being employed to curb the use of toxic materials in productive processes and prevent tragic accidents that can potentially claim the lives of thousands of people.
TORONTO, Sep 25 (Tierramérica).-
A green chemical revolution is underway that promises to be environmentally sustainable and profitable while reducing the risks of industrial disasters like the Bhopal, India gas leak in 1984.
"Green chemistry" has already turned maize into biodegradable plastics, developed non-toxic solvents and dramatically reduced the toxic byproducts from the manufacture of popular pharmaceuticals like ibuprofen. It is vital to the production of Toyota's new electric cars, made in part from kenaf, an annual grass plant.
"Green chemistry is about developing new products and processes which actually fit the 'triple' bottom line of environmental, economic and social sustainability," said Robin Rogers, a researcher and director of the University of Alabama's Center for Green Manufacturing.
Chemical processes are involved in nearly all manufactured products. Over the past decade, some chemists have been rethinking how to make these products without using toxic materials or producing toxic wastes.
Green chemistry is not "green-washing" of old technologies, it is a fundamental part of new technologies that work better, cost less, use less energy, and will be less polluting throughout the life cycle from raw material to ultimate disposition, Rogers told IPS.
"I consider this a 'Green Technology Revolution' to equate the imagery of the Industrial Revolution," he said.
Rogers and colleagues recently developed a new way to dissolve and use cellulose -- found in the cell walls of plants -- that will help drive the replacement of expensive and toxic petroleum-based plastics with plant materials.
Those countries, including developing countries, that implement green chemistry will be globally competitive and increase their market share because the technology is cheaper and better, he says.
"The Chinese National Natural Science Foundation is funding over 100 green chemistry projects," Rogers noted.
Green chemistry is an international issue because pollution and toxic releases can have an impact globally, says Kenneth Seddon, a professor of chemistry at Queens University in Belfast, Ireland.
China's 2005 benzene spill contaminated the water supply of millions of people there, and then drifted toward Russia's far east along the Songhua River, Seddon said in an interview.
In 2004, the DuPont company agreed to pay up to 600 million dollars for environmental damage caused by production of Teflon and Gore-Tex. General Electric will spend years and tens of millions of dollars to clean up PCBs (polychlorinated biphenyls) it discharged into the Hudson River.
India's Bhopal disaster killed at least 15,000 people and injured 150,000 to 600,000 more, following the accidental release in 1984 of 40 tons of methyl isocyanate (MIC) from a chemical plant owned by the U.S. chemical company Union Carbide. Union Carbide, now owned by Dow Chemical Company, agreed to pay 470 million dollars in damages, although it took years for most victims to receive compensation.
Avoiding pollution is one reason for developing countries to pursue green chemistry. Another is the fact that such countries will never be able to afford increasingly expensive petrochemicals, said Martyn Poliakoff of the University of Nottingham in Britain.
Poliakoff is working with chemists in Ethiopia to try and turn the "white flowers of Africa" -- the ubiquitous white plastic bags that litter the landscape -- into food for cows.
Along with the Procter & Gamble company, they hope to soon make plastic bags derived from local sugarcane.
"Ethiopia wouldn't have to import oil to make petroleum-based plastics, and the cows could eat the bags when they are thrown away," Poliakoff told IPS.
Green chemistry often brings lower costs, including reducing or eliminating the costs of disposing of toxic wastes, and reduces environmental impacts, all of which will make companies more competitive, says Seddon.
"Industry likes the concept but governments and academic research have yet to grasp the full potential," he added.
Fines, financial penalties and stiffer regulations have driven the chemical industry's interest, but they have been slow to adopt the new technology, says Philip Jessop, a research chemist at Queens University in Canada.
One reason is the cost of re-tooling existing manufacturing processes and, until recently, the absence of successful full-scale examples by companies, Jessop said in an interview.
"Now companies can see that they can save a lot of money," he said.
To produce one of its most popular drugs, the pharmaceutical giant Pfizer revised a complex four-step process that produced toxic waste into a one-step process using ethanol, saving millions of dollars, he said.
Other big pharma companies have made similar changes in their manufacturing processes, saved millions of dollars and now regularly win environmental awards from the U.S. Environmental Protection Agency.
Green chemistry is no more complex than traditional chemistry but it takes a different approach, one that considers the toxicity of materials and their byproducts when developing a new chemical process, Jessop says.
Jessop and his colleagues at Queens University recently revealed a new environmentally friendly and inexpensive process to separate water from crude oil. This has the potential to reduce the toxicity of current refining methods as well as reducing water use in Canada's tar sands oil production, he said.
DuPont's Teflon production pollution problem was also solved by rethinking how the molecules making up Teflon are put together. It now uses carbon dioxide as a surfactant rather than the toxic perfluorooctanoic acid (PFOA).
There is a global network of green chemistry advocates who have developed "The 12 Principles of Green Chemistry", with the first principle stating that "it is better to prevent waste than to treat or clean up waste after it has been created".
Since nearly all chemicals currently come from petrochemical sources, future chemists need not only to be trained in the 12 principles but also in how to understand the very different chemistry of plants and other living things, said Jessop.
Standard chemistry textbooks books devote little attention to green chemistry, and there are still misconceptions that it is either more expensive or ineffective, he added.
"And we need to move quickly on teaching green chemistry in developing countries," Jessop stressed.
Rogers agreed, saying that it is important to help prevent developing countries from "making the environmental mistakes of the past by adopting newer, cleaner technologies".
Green chemistry is trying to make the planet cleaner and safer and more profitable, concludes Seddon.
"Green chemistry is the conscience of chemistry, it is the way forward."
* This story is part of a series of features on sustainable development by IPS and IFEJ - International Federation of Environmental Journalists.