&EPA www.epa.gov/research science in ACTION INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE GREEN CHEMISTRY RESEARCH AND ENGINEERING Reducing hazardous substances through chemical product and process design Introduction EPA is leading the way with innovative research and technology in green chemistry for a more sustainable world. Green chemistry is the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Green chemists use a set of guiding principles and methodologies for reducing pollution at its source, the most desirable form of pollution prevention. In the design of new compounds, green chemists look at the entire life cycle of a chemical product, including raw material acquisition, design and manufacturing, consumer use, and finally, the sustainable recycling or disposal of the product. Pollution Prevention The Pollution Prevention Act of 1990 created a national policy to prevent or reduce pollution at its source whenever possible. Under the Act, EPA launched a research grants program in 1991 to encourage and support the design of chemicals and industrial processes that reduce pollution. In 1993, EPA began to expand its green chemistry and engineering research efforts and over the years has collaborated with academia, industry, government and non-government organizations to promote green chemistry applications through completely voluntary, non-regulatory partnerships. Through cooperative research and development agreements and technology licenses with industrial partners, EPA is providing innovative methods and tools that are being applied by the chemical and fuel industries. The partnerships have provided the chemical manufacturers and their customers with: • Reduced waste generation • Less costly end-of-pipe treatments • Inherently safer processes and products • Reduction in energy and non- renewable resources usage • Improved competitiveness Research Focus Areas EPA is playing a fundamental role in the green chemistry movement by providing innovations in three important areas for the chemical and fuel industries: • Catalysis • Green Synthesis • Process Intensification Catalysis Research A catalyst is a chemical that facilitates a chemical reaction to cause a desired chemical transformation. While catalysts do their job well, they are often expensive, may generate toxic waste, and may consume natural resources. EPA scientists are actively working to address these challenges. Continued on back 12 Principles of Green Chemistry Prevention: It's better to prevent waste than to treat or clean up waste afterwards. Atom Economy Design synthetic methods to maximize the incorporation of all materials used in the process into the final product. Less Hazardous Chemical Syntheses: Design synthetic methods to use and generate substances that minimize toxicity to human health and the environment. Designing Safer Chemicals: Design chemical products to affect their desired function while minimizing their toxicity. Safer Solvents and Auxiliaries: Minimize the use of auxiliary substances wherever possible and make them innocuous when used. Design for Energy Efficiency: Minimize the energy requirements of chemical processes and conduct synthetic methods at ambient temperature and pressure if possible. Use of Renewable Feedstocks: Use renewable raw material or feedstock whenever practicable. Reduce Derivatives: Minimize or avoid unnecessary derivatization if possible, which requires additional reagents and generate waste. Catalysis: Catalytic reagents are superior to stoichiometric reagents. Design for Degradation: Design chemical products so they break down into innocuous products that do not persist in the environment. Real-time analysis for Pollution Prevention: Develop analytical methodologies needed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances. Inherently Safer Chemistry for Accident Prevention: Choose substances and the form of a substance used in a chemical process to minimize the potential for chemical accidents, including releases, explosions, and fires. he U.S. Environmental Protection Agency Office of Research and Development ------- Nanoparticles are often used as catalysts, however they are frequently difficult to remove from the product mixture. EPA researchers discovered novel pathways to make green nanoparticles, created a process to make inherently less toxic nanoparticles, and developed innovative technology geared toward recovery, reuse and recyclability of nanomaterials. EPA scientists have demonstrated that nanoparticles containing an iron core can be coated with desired catalytic materials. By using an external magnet, the nanocatalyst can be recovered after the chemical process is complete. This discovery has reduced production costs, and eliminated waste. EPA research has generated nanocatalysts from benign plant extracts and sources such as tea and winery and agricultural waste that can effectively degrade contaminants in soil at hazardous waste sites. These "green- synthesized" particles replace other toxic nanomaterials and chemicals used to clean up hazardous sites, thus reducing clean-up costs and environmental impact. A company has licensed this proprietary technology for its clean-up business resulting in the creation of "green jobs." Through a collaborative effort, EPA also developed catalytic ozone technology that converts waste air pollutants such as methanol and sulfur compounds from pulp and paper mills to products that can be sold, such as methyl formate, used to make chemicals and manufacture pharmaceuticals. Other industries are also interested in this technology, which is projected to save paper mills up to $500,000 per paper mill annually and to reduce air pollution by 100 million pounds per site. Synthesis Research Chemical synthesis involves the initiation of chemical reactions to form a more complex molecule. Chemists sometimes use toxic solvents to facilitate this process. EPA has developed technology to replace toxic solvents with water, thus taking the harmful effects out of the chemical design process and reducing waste. Similarly, EPA is making a paradigm shift in the way nanoparticles are synthesized. Traditional methods involve grinding down particles from the large to the miniscule in size. This creates a lot of waste, causes potential hazards to workers, requires more toxic solvents and uses a lot of energy. Through innovative approaches, EPA has shown that you can "grow particles up" by adding material to molecules to create nanopaticles. The result: less toxic waste and less solvents used. Process Intensification Research Discoveries at EPA are paving the way for improved industrial production processes to manufacture chemicals and chemical products. Membrane technology developed by EPA for production of biofuels has shown in the pilot stage to significantly reduce energy use and provide a solution to help overcome the challenge of mass production of biofuels for use in cars and trucks. EPA technology has the potential to reduce energy costs by 50 percent for biofuel production by using membranes and other low-energy technologies to separate biofuels from industrial mixtures. The technological advances are paving the way for more efficient biofuel production that reduces its environmental impact on air quality. In another advance, the development of the spinning tube-in-tube reactor by EPA enables the production of thousands of chemicals in an efficient and sustainable way. The traditional process of chemical synthesis involves using solvents in reactor vessels, with capacity as large as 20,000 gallons. Using a table-size spinning tube-in-tube reactor, EPA has demonstrated that significant quantities of compounds can be synthesized without using large reactors and using significantly less energy and solvents, resulting in less waste. Reaction times are faster, enabling one spinning tube-in-tube reactor to produce 2 to 12 tons of compounds a year. But even before chemists go to the laboratory to design compounds, they can use EPA's software, called T.E.S.T (Toxicity Estimation Software Tool). This tool can assist the chemical industry with development of green chemistry alternative products and processes by predicting toxicity of molecules selected for possible chemical production. Finally, EPA is on the cutting edge of computational toxicology research to develop tools that can compare toxicity of chemicals. ToxCast and ToxPi are new tools that may be useful in the future to identify green chemical alternatives. CONTACT: John Leazer, EPA's Office of Research and Development, Sustainable Technology Division Director, leazer.john@epa.gov, 513-569-7840. June 2011 U.S. Environmental Protection Agency Office of Research and Development ------- |