Green chemistry refers to any practices that reduce waste, reduce energy consumption, use sustainable resources, or create less hazardous substances. There are 12 Principles of Green Chemistry that are considered when synthesizing greener chemicals and creating greener processes.
It is better to prevent waste than to treat or clean up waste after it has been created.
Hazardous waste disposal is costly. Yet, if it is not done correctly, the waste can impact our air, soil, and water. Preventing waste is a hallmark of green chemistry practices and a tool that we use a lot in general chemistry lab.
Consider how you can prevent creating hazardous waste when you design experiments. Consider that we can handle some waste in house by neutralizing it.
Synthetic methods should be designed to maximize incorporation of all materials used in the process into the final product.
While you have learned about percent yield as a way to consider how much product is actually made in a reaction, atom economy goes a step further and considers how much of all starting materials in a process are incorporated into the final product. This is mainly applicable to synthetic methods, such as those seen in organic chemistry.
Wherever practicable, synthetic methods should be designed to use and generate substances that possess little or no toxicity to human health and the environment.
This is a challenging frontier for chemists. Finding new chemicals and procedures that yield similar results can be difficult.
Consider when we as a society may need a chemical that is toxic by design. Consider barriers to getting scientists to use this principle.
Chemical products should be designed to preserve efficacy of function while reducing toxicity.
This is mostly considered in synthetic chemistry, including pharmaceuticals.
The use of auxiliary substances (e.g., solvents, separation agents, etc.) should be made unnecessary wherever possible and, innocuous when used.
We will primarily use water as a solvent in this course to meet this principle.
Energy requirements should be recognized for their environmental and economic impacts and should be minimized. Synthetic methods should be conducted at ambient temperature and pressure.
In general chemistry, we will meet this principle.
A raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable.
This primarily applies to organic synthesis.
Unnecessary derivatization (use of blocking groups, protection/deprotection, temporary modification of physical/chemical processes) should be minimized or avoided if possible, because such steps require additional reagents and can generate waste.
Again, this primarily applies to organic synthesis.
Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.
Again, this primarily applies to organic synthesis.
Chemical products should be designed so that at the end of their function they break down into innocuous degradation products and do not persist in the environment.
Again, this primarily applies to organic synthesis.
Analytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances.
We will use Vernier probes later this semester to monitor pH, temperature, and more.
Consider how technology can be used for real-time monitoring.
Substances and the form of a substance used in a chemical process should be chosen to minimize the potential for chemical accidents, including releases, explosions, and fires.
This sounds a lot like RAMP! Scientists in all fields must consider this in all that they do: research, teaching, and outreach.
American Chemical Society. 12 Principles of Green Chemistry. https://www-acs-org.proxy-sm.researchport.umd.edu/greenchemistry/principles/12-principles-of-green-chemistry.html (Accessed September 11, 2024)
American Chemical Society. Green Chemistry Pocket Guide. https://www-acs-org.proxy-sm.researchport.umd.edu/content/dam/acsorg/greenchemistry/redesign/principles/the-12-principles-of-green-chemistry-pocket-guide.pdf (Accessed September 11, 2024)
Maryland Department of the Environment. Hazardous Waste - Regulatory Oversight. https://mde.maryland.gov/programs/land/HazardousWaste/Pages/index.aspx (Accessed September 11, 2024)
Jimenez-Gonzalez, C.; Ponder, C.S.; Broxterman, Q.B.; Manley, J.B. Using the Right Green Yardstick: Why Process Mass Intensity Is Used in the Pharmaceutical Industry To Drive More Sustainable Processes.Organic Process Research & Development 2011 15 (4), 912-917 DOI: 10.1021/op200097d
American Chemical Society. The ACS Center for Lab Safety. Safer Experiments and Demonstrations. https://institute.acs.org/acs-center/lab-safety/education-training/safer-experiments.html (Accessed September 11, 2024)
ACS. Hazardous Waste and Disposal. https://www.acs.org/education/policies/middle-and-high-school-chemistry/safety/hazardous-waste-and-disposal.html (accessed Aug 1, 2024)