Is It Possible to Develop Environmentally Friendly Alternative Chemicals to CFCs?
In September 1987, twenty-four countries agreed to the Montreal Protocol on Substances that Deplete the Ozone Layer, which called for countries to cut down on their use of ozone-depleting chemicals such as chlorofluorocarbons (CFCs).1 These chemicals were commonly used as coolants for air conditioning and refrigeration, propellants in aerosol spray cans, solvents and foaming agents.2 The Protocol, which has now been ratified by 197 countries, resulted in a successful reduction in global CFC usage, but these chemicals were primarily replaced by hydrofluorocarbons (HFCs), which are greenhouse gases that contribute to climate change. Confronted with growing concerns about the global consequences of climate change, almost all parties to the Montreal Protocol met again in October 2016 to pass the Kigali Amendment, which requires the phaseout of HFCs.3 Because of the terms of this amendment, industries that use CFCs and HFCs will need to start looking for specialty chemical companies that offer alternative chemicals and blends.
Identifying New Materials to Replace CFCs
Because CFCs are used in such a wide range of products, there probably won’t be just one environmentally friendly chemical that works as a replacement in every product. For example, the best alternative to include in an air conditioner may not be an equally effective foaming agent. Indeed, early studies on alternatives to CFCs and HFCs indicate that certain alternatives work better in different applications.4 Using modeling software that makes it possible to predict the chemical properties and behaviors of different materials based on their molecular structures, scientists can determine which alternatives might be best suited to each purpose.
There is also evidence that some of the proposed alternatives to CFCs and HFCs can actually make refrigerators and air conditioners more energy efficient. Although this is not a strict requirement of the Montreal Protocol, it can lower the economic and environmental costs of these products, so alternative chemicals that improve energy efficiency will be particularly appealing to manufacturers. With computer simulations, scientists can identify the most promising chemical candidates, prioritize them for development and offer them to refrigerator and air conditioning manufacturers as soon as possible.
Testing Different Chemical Blends
While many of the substances that are currently used as coolants, propellants, foaming agents and solvents only contain one chemical—a CFC or an HFC—some of the proposed alternatives contain blends of multiple chemicals. Scientists may explore some of the following options:
Combining two alternative chemicals
Ideally, chemical blends that replace currently used HFCs and CFCs will be comprised entirely of environmentally friendly alternatives.
Combining an HFC or CFC with an alternative chemical
The Montreal Protocol does not ban HFCs or CFCs altogether, so it may be possible to include them in an alternative blend. Combining an HFC or CFC with an environmentally friendly alternative reduces the total amount of the hazardous chemical that is required to produce the necessary coolant or propellant effect, so these options will still help with the phaseout of HFCs and CFCs.
Combining an HFC with a CFC
Although not the preferred option, blending an HFC with a CFC lowers the amount of each that needs to be used. As a result, there will be less ozone depletion (caused by the use of the CFC) or greenhouse gas emission (caused by the use of the HFC) than there would be if either one was used alone. This may be a good option in the early stages of the HFC phaseout, until a better alternative can be developed.
Chemical modeling software can help researchers learn more about the properties of each individual chemical in the blend and how they interact with each other to produce certain behaviors. This information can provide insight into whether the blend may be a suitable replacement for the currently used CFCs or HFCs in a certain application, without forcing researchers to conduct laborious benchtop experiments just to get a general idea of the blend’s properties. Moreover, computer modeling allows scientists to make infinitesimal adjustments to chemical concentrations and re-run tests so that they can quickly hone in on the ideal ratio of chemicals to use in the blend.
Staying Ahead of the Legal and Environmental Consequences of Using HFCs and CFCs
Now that the Kigali Amendment has been passed, it is important to start using environmentally friendly alternatives to CFCs and HFCs as quickly as possible. Modeling software improves research efficiency by reducing the number of time-consuming benchtop tests that need to be conducted on potential CFC and HFC replacements, since many of their properties can be determined with simulations.
Improvements in this technology also make it possible to automate repetitive modeling tasks by enabling the creation of reusable modeling and simulation protocols. Not only does this speed the overall development process, but it allows researchers to avoid wasting their time dealing with the mundane technicalities of modeling. Instead, they can focus their efforts on innovation, finding ways to develop environmentally friendly materials that can help combat the threats of ozone depletion and climate change in order to ensure a healthy planet for generations to come.
BIOVIA Materials Studio is a modeling and simulation environment that facilitates in-depth study of the properties and behavior of a wide range of materials. Contact us today to learn more about how this software can help researchers at your specialty chemical firm develop solutions to the most pressing environmental challenges that the world faces today.
- “Montreal Protocol on Substances that Deplete the Ozone Layer,” 2016, http://www.theozonehole.com/montreal.html ↩
- “CFC substitutes: Good for the ozone layer, bad for climate?” February 24, 2012, https://www.sciencedaily.com/releases/2012/02/120224110737.html ↩
- “Nations, Fighting Powerful Refirigerant That Warms Planet, Reach Landmark Deal,” October 15, 2016, http://www.nytimes.com/2016/10/15/world/africa/kigali-deal-hfc-air-conditioners.html ↩
- “Climate-friendly alternatives to HFCs and CFCs,” August 17, 2016, http://ec.europa.eu/clima/policies/f-gas/alternatives/index_en.html ↩