CFCS, HFCS AND THEIR CASUALTIES
Editor's Note: Lia D.B. ('17) wrote this paper investigating the history of CFCs and HFCs for her organic chemistry class.
CFCs, also known as chlorofluorocarbons, were discovered in the 1930’s as the “perfect refrigerant.” At the time, CFCs seemed to offer the ideal refrigerant as they fit all of the requirements and more. CFCs have an ideal boiling point which allows them to vaporize and then return to liquid state by compression within the defined temperature range of the refrigerant process (LeCouteur and Burreson, 2004). Additionally, CFCs have extremely stable atomic structures, causing them to be nonflammable, nontoxic, and just about odorless (LeCouteur and Burreson). At the time, CFCs’ stability revolutionized the world of refrigeration, both in the home and in foreign trade. Before the twenties, the majority of households relied on ice boxes to keep food cold, and even still many fruits were canned and meats were salted. CFC’s stability meant that countries could not only ship their produce across seas without worrying about it spoiling, but that they also didn’t have to worry about their ships catching on fire due to flammable refrigerants. Beyond refrigeration, this stability proved to be beneficial in other ways as it reacted with almost nothing, making it a great propellant in a number of substances such as hair sprays, whipped creams, and pesticides (LeCouteur and Burreson).
Unfortunately, it wasn’t long until the dark side of the “miracle” molecules were exposed. In the 1970s it was quickly discovered that CFCs’ stability, the exact thing that made them seem so attractive in the first place, caused tremendous problems to our ozone layer (LeCouteur and Burreson). In fact, CFCs are so stable that they do not break down under normal chemical reactions. Instead, CFCs end up floating up to the stratosphere where they eventually get broken down by ultraviolet light. When CFCs come into contact with the ozone molecules the chlorine atoms act as a catalyst and increase the rate at which the ozone molecules break down. This means that the chlorine atoms don’t get used up in the reaction, and will instead destroy a hundred thousand ozone molecules before they ever get deactivated (LeCouteur and Burreson).
Ironically enough, from an economic standpoint, this very idea of a chlorine atom acting as a catalyst is what made CFCs so profitable in the first place. This made it very cheap to manufacture CFCs because, in theory, the initiation process where the two chlorine atoms split only needs to happen once, and afterwards the cycle can keep repeating without anymore energy added to the system. Since the signing of the Montreal Protocol in 1987, CFCs have been, for the most part, phased out of our appliances and lifestyles (LeCouteur and Burreson). After the discovery of CFCs’ dramatic effect on the environment, a number of compounds have been introduced, though CFCs’ cheap manufacturing process has made it extremely difficult to come up with another class of compounds which are not only better for the environment, but also as profitable to produce.
One of the most well known class of compounds developed to replace CFCs are HFCs, also known as hydrofluorocarbons. HFCs were originally labeled as non threatening to the environment because they have more hydrogen atoms than CFCs, allowing most of them to break down before reaching the stratospheric ozone layer. Additionally, HFCs do not contain chlorine atoms, so even if some make it to the stratospheric ozone layer, they do not cause the same amount of harm (Empa, 2012). In an article published in Science Daily, Empa writes that by implementing the Montreal Protocol, the equivalent of 10 billion tonnes of carbon dioxide gas was prevented from getting released into the atmosphere (Empa). On the other hand, it can also be argued that HFCs are causing just as many problems as they were intended to solve. While HFCs are friendlier to the ozone layer, they are also harmful greenhouse gasses. For instance, HFCs are 12,000 times more powerful in causing climate change than carbon dioxide (Magill, 2015). Because of that, many scientists are beginning to fear that the positive effect that the Montreal Protocol had on the environment will very soon be undone with the effects of HFCs and the Obama Administration Climate Change Plan is banning them in favor of “more-climate friendly gas” (Magill).
Moving forward, how do we find the most climate-friendly option? While HFCs have tremendous greenhouse gas effects, many scientists worry that alternatives to HFCs might be less efficient and enlarge our carbon footprint by increasing the amount of electricity needed to cool a room. While HFCs ended up not being as harmful to the ozone layer as CFCs were, they still were tremendously bad for the environment in terms of their greenhouse gas effects. By solving one problem, we created another, adding on to what seems to be a never ending cycle of scientists trying to fix previous scientists’ problems, but in reality just creating another one. How do we break this cycle? Are we really ever advancing or just simply creating a whole new set of problems?
Works Cited
Empa. (2012, February 24). CFC substitutes: Good for the ozone layer, bad for climate?.
ScienceDaily. Retrieved February 25, 2016 from www.sciencedaily.com/releases/2012/02/120224110737.htm
Magill, B. (2015, July 7). EPA Bans a Gas That Once Helped Save the Ozone Layer.
Retrieved February 25, 2016, from http://www.climatecentral.org/news/epa-bans-greenhouse-gas-19197
Unfortunately, it wasn’t long until the dark side of the “miracle” molecules were exposed. In the 1970s it was quickly discovered that CFCs’ stability, the exact thing that made them seem so attractive in the first place, caused tremendous problems to our ozone layer (LeCouteur and Burreson). In fact, CFCs are so stable that they do not break down under normal chemical reactions. Instead, CFCs end up floating up to the stratosphere where they eventually get broken down by ultraviolet light. When CFCs come into contact with the ozone molecules the chlorine atoms act as a catalyst and increase the rate at which the ozone molecules break down. This means that the chlorine atoms don’t get used up in the reaction, and will instead destroy a hundred thousand ozone molecules before they ever get deactivated (LeCouteur and Burreson).
Ironically enough, from an economic standpoint, this very idea of a chlorine atom acting as a catalyst is what made CFCs so profitable in the first place. This made it very cheap to manufacture CFCs because, in theory, the initiation process where the two chlorine atoms split only needs to happen once, and afterwards the cycle can keep repeating without anymore energy added to the system. Since the signing of the Montreal Protocol in 1987, CFCs have been, for the most part, phased out of our appliances and lifestyles (LeCouteur and Burreson). After the discovery of CFCs’ dramatic effect on the environment, a number of compounds have been introduced, though CFCs’ cheap manufacturing process has made it extremely difficult to come up with another class of compounds which are not only better for the environment, but also as profitable to produce.
One of the most well known class of compounds developed to replace CFCs are HFCs, also known as hydrofluorocarbons. HFCs were originally labeled as non threatening to the environment because they have more hydrogen atoms than CFCs, allowing most of them to break down before reaching the stratospheric ozone layer. Additionally, HFCs do not contain chlorine atoms, so even if some make it to the stratospheric ozone layer, they do not cause the same amount of harm (Empa, 2012). In an article published in Science Daily, Empa writes that by implementing the Montreal Protocol, the equivalent of 10 billion tonnes of carbon dioxide gas was prevented from getting released into the atmosphere (Empa). On the other hand, it can also be argued that HFCs are causing just as many problems as they were intended to solve. While HFCs are friendlier to the ozone layer, they are also harmful greenhouse gasses. For instance, HFCs are 12,000 times more powerful in causing climate change than carbon dioxide (Magill, 2015). Because of that, many scientists are beginning to fear that the positive effect that the Montreal Protocol had on the environment will very soon be undone with the effects of HFCs and the Obama Administration Climate Change Plan is banning them in favor of “more-climate friendly gas” (Magill).
Moving forward, how do we find the most climate-friendly option? While HFCs have tremendous greenhouse gas effects, many scientists worry that alternatives to HFCs might be less efficient and enlarge our carbon footprint by increasing the amount of electricity needed to cool a room. While HFCs ended up not being as harmful to the ozone layer as CFCs were, they still were tremendously bad for the environment in terms of their greenhouse gas effects. By solving one problem, we created another, adding on to what seems to be a never ending cycle of scientists trying to fix previous scientists’ problems, but in reality just creating another one. How do we break this cycle? Are we really ever advancing or just simply creating a whole new set of problems?
Works Cited
Empa. (2012, February 24). CFC substitutes: Good for the ozone layer, bad for climate?.
ScienceDaily. Retrieved February 25, 2016 from www.sciencedaily.com/releases/2012/02/120224110737.htm
Magill, B. (2015, July 7). EPA Bans a Gas That Once Helped Save the Ozone Layer.
Retrieved February 25, 2016, from http://www.climatecentral.org/news/epa-bans-greenhouse-gas-19197
