Green chemistry is an approach or manner of conducting research, product development and subsequent chemical manufacturing in an economically efficient manner with concurrent benefits to society, and particularly for the environment.
The application of green chemistry metrics has been adopted by many major chemical manufacturers. More broadly, it is now a major driver of innovation across a range of industries for the development of new materials and processes. This approach, demonstrating social responsibility, not only leads to improved functionality of chemicals, but also has a positive impact on human health and the environment. The ability to develop new, improved materials and processes requires regulators and companies to develop appropriate policies based on sound science and engineering that will improve safety and lessen adverse environmental impact. Green chemistry has been shown to be commercially viable for developing products or services that have enhanced performance qualities and/or cost savings in addition to reducing the environmental footprint of their businesses.
The 12 principles of green chemistry were first articulated by Paul Anastas and John Warner in 1998 and essentially encouraged a cohesive way of thinking about chemical research and development, which can then be further translated into manufacturing. These 12 principles are:
- Prevention. Preventing waste is better than treating or cleaning up waste after it is created.
- Atom economy. Synthetic methods should try to maximize the incorporation of all materials used in the process into the final product.This means that less waste will be generated as a result.
- Less hazardous chemical syntheses. Synthetic methods should avoid using or generating substances toxic to humans and/or the environment.
- Designing safer chemicals. Chemical products should be designed to achieve their desired function while being as non-toxic as possible.
- Safer solvents and auxiliaries. Auxiliary substances should be avoided wherever possible, and as non-hazardous as possible when they must be used.
- Design for energy efficiency. Energy requirements should be minimized, and processes should be conducted at ambient temperature and pressure whenever possible.
- Use of renewable feedstocks. Whenever it is practical to do so, renewable feedstocks or raw materials are preferable to non-renewable ones.
- Reduce derivatives. Unnecessary generation of derivatives—such as the use of protecting groups—should be minimized or avoided if possible; such steps require additional reagents and may generate additional waste.
- Catalysis. Catalytic reagents that can be used in small quantities to repeat a reaction are superior to stoichiometric reagents (ones that are consumed in a reaction).
- Design for degradation. Chemical products should be designed so that they do not pollute the environment; when their function is complete, they should break down into non-harmful products.
- Real-time analysis for pollution prevention. Analytical methodologies need to be further developed to permit real-time, in-process monitoring and control before hazardous substances form.
- Inherently safer chemistry for accident prevention. Whenever possible, the substances in a process, and the forms of those substances, should be chosen to minimize risks such as explosions, fires, and accidental releases.
Green Chemistry and the United Nations Sustainable Development Goals
The United Nations Sustainable Development Goals provide a blueprint to achieve and better and sustainable future for all.
The application of green chemistry will assist many of these goals including:
- Develop more productive, and safe, fertilisers (Goal 2)
- Reduction in pollution and the use of hazardous chemicals improving on human health and the environment (Goal 3)
- Improved energy and water efficiency in manufacturing (Goals 6 & 7)
- Cost effective methods for providing clean water (Goal 6)
- Improved production and storage of renewable energy (Goal 7)
- Develop clean and environmentally sound technologies and industrial processes (Goal 9)
- Reduction in waste during manufacturing, improved recycling and efficient use of renewable resources (Goal 12)
- Reduction in emission of green house gases during manufacturing (Goal 13)
- Reduction in marine pollution from manufacturing and from the use, or misuse, of products (Goal 14)