Green Chemistry is a set of principles for the design of products and processes to reduce or eliminate the use and generation of hazardous substances.
Everything around us is made of chemicals. We are made of chemicals; our friends are made of chemicals; the food we eat and the air we breathe are all chemicals. Modern life would not be possible without industrially produced chemicals and the products that contain them. That is why green chemistry is an important field: it helps in the design of chemical products and processes that can sustainably and safely enhance our lives. Our food production, energy systems, and material sourcing can all benefit from green chemistry principles.
How is a green chemist different from a regular chemist?
Chemistry is the study of matter and the changes it can undergo.
Often when people think of chemistry, they think of explosions, colorful precipitates, reactions giving off toxic gases, and other changes that likely have little to do with environmental sustainability.
Green chemists still work with reactions and develop new materials. However, they make every effort to make sure there are no detrimental effects to the environment or public health.
Professor in the Practice of Chemistry for the Environment
Center for Green Chemistry and Green Engineering at Yale
This video from Dr. Paul Anastas explains why green chemistry is critical for future efforts to achieve genuine sustainability.
Did you know...
Globally, 94% of extracted raw material ends up directly as waste compared to 6% that goes into a finished product.
Waste, we need to recognize, is a man-made concept, in nature, there is no waste: every time a waste is generated, an organism evolves to use that waste as a feedstock.
- Dr. Paul Anastas, CNBC 2020
This innovation in design means that not only are the chemicals less hazardous, but they are also more judiciously used; material production can be done in a way that reduces the raw material needed and minimizes overall waste. On average, the ratio of product to waste for pharmaceutical manufacturing is 1lb to 1 ton. Green chemistry uses the principles of chemistry to identify opportunities to reduce materials and eliminate waste.
Where did green chemistry start, and where is it going?
While the EPA Chief of the Industrial Chemistry Branch and as the U.S. Green Chemistry Program Director, Dr. Paul Anastas introduced the field of green chemistry about 30 years ago. Since then, green chemistry has gone global, with more than a dozen scientific journals dedicated to green chemistry. Businesses pursue green chemistry innovations because it grows their economic bottom-line with increased efficiency and top-line as the products are new and of higher quality. Green chemistry touches every business sector, from agriculture to technology, plastics, and cosmetics.
Why green chemistry?
Green chemistry goes beyond an understanding of the function of chemicals. It requires an intentional approach to analyzing their performance and impact on our environment and health. In conventional production, chemicals can deteriorate and deplete important raw materials, like fossil fuels. Green chemistry strives to redesign chemicals themselves and how chemicals are used, in a way to reduce or eliminate harmful effects.
When green chemistry principles are used to improve the design of material production, products can be made with fewer hazardous substances and reduce waste.
To help focus efforts, Dr. Paul Anastas and Dr. John Warner published the 12 principles of green chemistry. These principles can serve as a checklist of recommendations that chemists can use to reduce waste and toxicity of materials and produce safer higher quality goods. The principles are intended to be used from the sourcing of the raw material to the end of useful life for a product and everything in between.
The 12 principles of green chemistry are:
1. Prevent waste
It is better to prevent waste than to treat or clean up waste after it’s been created.
3. Design less hazardous chemical syntheses
Create chemical reactions and synthetic routes to be as safe as possible.
5. Use safer solvents and reaction conditions
Use only the safest solvent available for any given step. The use of supplementary substances should be minimized to reduce waste, and nontoxic when used.
7. Use renewable feedstocks
Use chemicals that are made from renewable (i.e. plant-based) sources whenever possible.
9. Use catalysts, not stoichiometric reagents
Increase selectivity by using a catalyst, additionally minimize waste and reduce reaction times and energy demands.
11. Analyze in real-time to prevent pollution
Evaluate chemical reactions in real-time to prevent the creation and emissions of any potentially hazardous and polluting substances.
2. Maximize atom economy
Design methods that maximize the number of atoms from inputs that are present in the final product, in order to reduce molecular waste.
4. Design safer chemicals and products
Design chemicals and products to perform their functions while being safe to humans and the environment.
6. Increase Energy efficiency
Choose the least energy-intensive chemical route, in order to increase energy efficiency.
8. Avoid chemical derivatives
Minimize or avoid unnecessary chemical derivatives to reduce reaction steps, resources required, and waste created.
10. Design chemicals and products to degrade after use
Prioritize chemicals and products that break down and degrade easily into something non-toxic, and that does not accumulate or persist in the environment.
12. Minimize the potential for accidents
Implement chemical procedures should be safe and minimize the risk for accidents.
You do not need to be a chemist to engage in green chemistry!
While there are bench lab scientists working on green chemistry, anyone from entrepreneurs to advocates can implement the core principles. Some major themes in the current practical application of green chemistry include:
Reducing reliance on nonrenewable energy sources, exploring renewable sources to replace depleting resources like fossil fuels
Reducing industrial carbon footprints with methods like carbon capture and storage, which resuses or stored CO2 so it will not enter the atmosphere
Breaking down landfill waste by designing chemicals and products to degrade
Turning our waste into something useful again (for example, using agricultural waste to make biodegradable plastic to replace petroleum-based plastic).