Guest Post from Boropharm, Inc.
The chemical manufacturing industry touches every aspect of modern life. From apples to Zoloft, there is virtually nothing that doesn’t require chemicals to produce. In the 1990s, amidst growing awareness of the hazardous impacts of the chemical industry, the green chemistry revolution was launched by American chemists Paul T. Anastas and John Warner. Their 12 Principles of green chemistry continue to guide industry’s efforts to prevent negative effects on people and the planet.
While it may seem obvious that greener chemistry is a good idea, as is true for most things, there are pros and cons to green chemical manufacturing. In order to consider them, it’s helpful to look more closely at what the chemical industry does.
The Recipe
If you took chemistry in high school, then you’ve learned the fundamental processes involved in chemical manufacturing: substances are combined to create new substances. The materials you start with are reactants, and when you put them together they transform to become products. At least one of those products is the desirable chemical. Everything else left over from the reaction is a waste.
Often, reactants are mixed in a solvent, which is a liquid that breaks them down and sets the stage for the transformation. Sometimes a catalyst is required. This is a substance that helps the reaction take place, but isn’t used up in the reaction. Solvents and catalysts can often be purified and reused. Reactions may also require special conditions in order to happen, like high temperatures or low pressures. Creating these conditions can require a lot of energy.
The Principles
When Anastas and Warner developed the 12 principles, they examined every aspect of the above process to see how chemistry could be made cleaner and safer. Green chemistry includes everything from using reactants that are renewable resources to ensuring chemical products eventually degrade into something safe rather than persisting in the environment.
The Pros
There are many potentially positive outcomes of green chemistry. Going green can benefit society as well as manufacturers. For example:
– Using sustainable and renewable resources for reactants and catalysts preserves resources for future generations.
– It can also save manufacturers money because sustainable resources are often plentiful, and therefore cheap. An example of this is using Nickel as a catalyst rather than Palladium.
- When less waste is produced in a reaction, there is less potentially hazardous material being released into the environment.
– Reducing waste also saves manufacturers money on materials (because more starting material can be sold as product) and on the costs of waste remediation.
– Developing reactions that take place at ambient temperatures and pressures reduces energy consumption.
– The production of safer chemical products prevents human illness and the poisoning of the human environment.
- It also prevents class actions lawsuits, which are expensive and damaging to a company’s reputation.
The Cons
There are some potential downsides to the move toward greener chemical manufacturing. For example:
- When new, greener reactions are developed, new equipment or even whole new chemical plants may be necessary. The set-up costs can be prohibitive.
-
When new, greener reactions are developed, the production of a chemical may need to halt completely while the manufacturer reconfigures manufacturing plants. If the chemical is a medication, for example, this can have negative impacts on the public.
-
Unintended consequences can have severe impacts on the public. Older chemical processes have been around long enough that their potential hazards are well understood. Newer materials may appear greener at first, but problems may reveal themselves later. For example, Tetrachloroethylene was supposed to make dry cleaning greener, however it proved to be just as carcinogenic as older chemicals.
The chemical industry and the public are in agreement about the desirability of greener chemistry for the benefit of humanity and our planet. In every step toward accomplishing that goal, however, careful consideration needs to be given to the pros and cons of each new change that is implemented.
References:
Philip Jessop and Walter Leitner,“Thoughts on Green Chemistry from the new Chair of the Editorial Board.“ Green Chem., 2017, 19, 15-17. DOI: 10.1039/C6GC90126C
http://pubs.rsc.org/-/content/articlehtml/2017/gc/c6gc90126c
Roger A. Sheldon, “Green chemistry and resource efficiency: towards a green economy.” Green Chem., 2016, 18, 3180-3183. DOI: 10.1039/C6GC90040B.
http://pubs.rsc.org/-/content/articlehtml/2016/gc/c6gc90040b