Office of Research and Development
Green Chemistry Research
Science in Action
EPA Green Chemistry Video (6:22 mins)
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 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 Renewable Feedstock: Use renewable raw material or feedstock rather 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.
Green chemistry is the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Green chemistry uses a set of guiding principles and methods for reducing pollution at its source. See the sidebar at the right for a list of the 12 principles.
Green chemists look at the entire life cycle of a chemical product—including raw material acquisition, design and manufacture of the product, consumer use, and finally the sustainable recycling or disposal of the product.
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 industry:
A catalyst is a chemical that assists a chemical reaction to affect a desired chemical transformation using less energy and/or less time. 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.
Nanoparticles are often used as catalysts; however, they are frequently difficult to remove from the product mixture. EPA researchers discovered new ways to make green nanoparticles, created a process to make them naturally less toxic nanoparticles, and developed innovative technology geared toward easy recovery, reuse, and recyclability of nanomaterials.
EPA scientists have demonstrated that nanoparticles containing an iron core can be coated with desired and even inexpensive 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.
Chemical synthesis involves the initiation of chemical reactions to form a more complex molecule. Chemists use toxic solvents to assist this reaction 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 change 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 solvents that are more toxic, and uses a lot of energy.
Through innovative approaches, EPA has shown that you can “grow particles up” by taking material at the molecular level and adding to it to make the nanopaticles. The result is less toxic waste and fewer solvents used.
Discoveries at EPA are paving the way for improved production processes for industry to manufacture chemicals and chemical products.
Membrane technology developed by EPA for production of biofuels has resulted in tremendous reduction in energy use and provided a solution to overcoming the challenge of mass production of the biofuel for use in cars and trucks.
In another advance, the development of the spinning tube reactor by EPA enables the production of thousands of chemicals in an efficient and sustainable way. With a table-sized spinning tube reactor, EPA has demonstrated that a compound can be developed without large reactors, using significantly less energy and fewer solvents than with traditional methods.
Reaction times are greater, enabling one spinning tube reactor to product 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 TEST (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 such tools that may be useful in the future to identify green chemical alternatives.