The Dangers of Chlorofluorocarbons
In her organic chemistry class, Esme L. ('19), explored the dangerous effects that use of chlorofluorocarbons in everyday products can cause to the environment.
The ability to keep things cool has been around for around 4,000 years, relying on the scientific principle that solid ice absorbs heat from its surrounds while it melts. This classic theory involves the liquid water produced from the melting process draining away as a new supply of ice is added: solid and liquid phases. The newer, more familiar process of refrigeration involves a continuous cycle of liquid and vapor phases in which the liquid vaporizes by absorbing the heat from its surroundings, then compresses back into a liquid, which causes it to cool its surroundings. Though this process of refrigeration seems rather straightforward, it first requires a refrigerant, a compound which vaporizes and liquefies within a certain temperature range (Le Couteur and Burreson, 2004).
In the early stages of the refrigeration process, scientists used ether, ammonia, methyl chloride, and sulfur dioxide for the chemical cooling process. Though each of these compounds technically fit the criteria of a refrigerant by vaporizing and compressing within the right temperature range and absorbing a relatively large amount of heat during its vaporization process, they all had negative aspects to being a refrigerant as well. Each of them either decomposed, was a fire hazard, was poisonous, or smelled terrible - sometimes multiple of these. In an attempt to find new, safer refrigerants, chlorofluorocarbons (CFCs) were found, fulfilling the criteria of its role in an astonishing manner. Once discovered, other uses for CFCs were found as well. Since they reacted with almost nothing, they made ideal propellants for any substance that could possibly be applied via aerosol. Hair sprays, foaming shaving creams, carpet cleaners, and insecticides were just a few of the many ways CFCs were put to use (Le Couteur and Burreson).
While CFCs were originally thought to be the perfect solution to all propellant and refrigeration needs, it was soon discovered that they were hazardous to our environment. Due to CFCs’ stability, they don’t break down in the same manner that other, less stable compounds do. Once CFCs are released into the atmosphere, they drift around for years only to rise into the stratosphere. Within the stratosphere, there is a layer known to us as the ozone layer, a layer made up of innumerable O3 molecules. Once the CFCs reach the ozone layer, a radical chain mechanism begins, breaking up the ozone layer via chlorination. Once the ozone molecules are broken up, they are almost unable to reform because the bond between chlorine or fluorine and oxygen is much stronger than that between oxygen and oxygen (Le Couteur and Burreson). Although it seems as if the ozone is irrelevant as it’s so far away from Earth’s surface, the ozone layer blocks most of the sun’s high frequency rays. These UV rays from the sun can cause skin cancer and cataracts in humans and reproductive issues in fish, crabs, and frogs (Handwerk, 2010). Due to the risk of cancer and disruption of animals’ reproductive process, CFCs were deemed too harmful to continue using.
In 1987, many countries signed the Montreal Protocol committing to phase out the use of CFCs and ultimately establishing a ban on the production and use of them entirely. Today, hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) are used in the process of refrigeration. Each compound either does not contain chlorine or is more easily oxidized in the atmosphere causing them to be less likely to reach the stratosphere (ozone layer) (Le Couteur and Burreson). However, even compounds that work as refrigerants and do not destroy our ozone layer have a downside. The newer replacements for CFCS are generally more expensive to produce and less effective than CFCs. For example, one of the main ozone-destroying refrigerants, CFC-12, could be replaced with HFC-134a. Except, CFC-12 is made up of two basic elements, making it easily manufacturable while HFC-134a is much more difficult to manufacture, in turn, making it more expensive to manufacture. Earlier in the development process, chemical engineers said that the replacement chemical were likely to cost up to three times the cost of CFC-12 to produce and might not last as long (Brown, 1989). And while HFC-134a would not affect the ozone layer, it would increase the trapping of solar heat by the atmosphere. As scientists continued to grapple with the ever developing discovery of chlorofluorocarbon substitutes, engineers also considered designing an entirely new refrigeration system without the conventional compression system (Brown, 1990).
While the use of CFCs has greatly benefited technology worldwide, Dr. Manzer of E. I. du Pont de Nemours & Company, stated in 1990 “There's no question that the world will learn to get along without CFC's. The questions that remain have to do with cost - the trade-off costs, as well as the money'’ (Brown, 1990).
As studies continue, the use of HFCs is still being debated. While they’re much better for the environment than CFCs, they still tend to come with a host of environmental issues. An article published in 2015 by the World Resources Institute touches upon various ways the United States can reduce their use of hydrofluorocarbons. Major manufacturers, such as Honeywell and Arkema, are producing alternatives to HFCs, compounds that have less of an effect on the environment. The alternatives tend to include compounds such as carbon dioxide (CO2) and hydrocarbons as well as other synthetic materials. Companies such as Coca-Cola, Pepsi, and Ben and Jerry’s have begun to use coolers with low or zero global warming potential (GWP) HFCs. And although these environmentally friendly compounds may come with higher costs up front, there’s a high probability they will offer net savings over time. The immediate fees include mostly replacement of equipment or the facilitation of vehicle/machinery redesign. Once the Montreal Protocol began phasing out the use of CFCs, a movement of technological development and investment in a new generation of air conditioning and refrigeration systems was spurred, creating both benefits to public health and environmental safety as well as lifetime savings for consumers. The Environmental Protection Agency even found that most products did not cost more than their predecessors, and some machinery was actually cheaper to maintain (Igusky).
Ultimately, it comes down to the sacrifices the population is willing to make. While it may take time and money to replace the existing systems with more environmentally sound machinery, it could ultimately save consumers a considerable amount of money and make the world a safer place to live for its inhabitants.
Works Cited
Brown, Malcolm W. (1989, March 7). In Protecting the Atmosphere, Choices are Costly and Complex. The New York Times. Retrieved from http://www.nytimes.com/1989/03/07/science/in-protecting-the-atmosphere-choices-are-costly-and-complex.html?pagewanted=all.
Brown, Malcolm W. (1990, July 17). Grappling With the Cost of Saving Earth’s Ozone. The New York Times. Retrieved from http://www.nytimes.com/1990/07/17/science/grappling-with-the-cost-of-saving-earth-s-ozone.html?pagewanted=all.
Handwerk, Brian. (2010, May 7). Whatever Happened to the Ozone Hole? The New York Times. Retrieved from https://news.nationalgeographic.com/news/2010/05/100505-science-environment-ozone-hole-25-years/.
Igusky, Kristin. (2015, March 3). Reducing HFCs in the US Would Benefit Consumers and the Climate. The World Resources Institute. Retrieved from http://www.wri.org/blog/2015/03/reducing-hfcs-us-would-benefit-consumers-and-climate.
Le Couteur, Penny and Jay Burreson. (2004). Chlorofluorocarbon Compounds. Napoleon’s Buttons: 17 Molecules That Changed History (pp. 308-329). New York: Jeremy P. Tarcher/Penguin.
In the early stages of the refrigeration process, scientists used ether, ammonia, methyl chloride, and sulfur dioxide for the chemical cooling process. Though each of these compounds technically fit the criteria of a refrigerant by vaporizing and compressing within the right temperature range and absorbing a relatively large amount of heat during its vaporization process, they all had negative aspects to being a refrigerant as well. Each of them either decomposed, was a fire hazard, was poisonous, or smelled terrible - sometimes multiple of these. In an attempt to find new, safer refrigerants, chlorofluorocarbons (CFCs) were found, fulfilling the criteria of its role in an astonishing manner. Once discovered, other uses for CFCs were found as well. Since they reacted with almost nothing, they made ideal propellants for any substance that could possibly be applied via aerosol. Hair sprays, foaming shaving creams, carpet cleaners, and insecticides were just a few of the many ways CFCs were put to use (Le Couteur and Burreson).
While CFCs were originally thought to be the perfect solution to all propellant and refrigeration needs, it was soon discovered that they were hazardous to our environment. Due to CFCs’ stability, they don’t break down in the same manner that other, less stable compounds do. Once CFCs are released into the atmosphere, they drift around for years only to rise into the stratosphere. Within the stratosphere, there is a layer known to us as the ozone layer, a layer made up of innumerable O3 molecules. Once the CFCs reach the ozone layer, a radical chain mechanism begins, breaking up the ozone layer via chlorination. Once the ozone molecules are broken up, they are almost unable to reform because the bond between chlorine or fluorine and oxygen is much stronger than that between oxygen and oxygen (Le Couteur and Burreson). Although it seems as if the ozone is irrelevant as it’s so far away from Earth’s surface, the ozone layer blocks most of the sun’s high frequency rays. These UV rays from the sun can cause skin cancer and cataracts in humans and reproductive issues in fish, crabs, and frogs (Handwerk, 2010). Due to the risk of cancer and disruption of animals’ reproductive process, CFCs were deemed too harmful to continue using.
In 1987, many countries signed the Montreal Protocol committing to phase out the use of CFCs and ultimately establishing a ban on the production and use of them entirely. Today, hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) are used in the process of refrigeration. Each compound either does not contain chlorine or is more easily oxidized in the atmosphere causing them to be less likely to reach the stratosphere (ozone layer) (Le Couteur and Burreson). However, even compounds that work as refrigerants and do not destroy our ozone layer have a downside. The newer replacements for CFCS are generally more expensive to produce and less effective than CFCs. For example, one of the main ozone-destroying refrigerants, CFC-12, could be replaced with HFC-134a. Except, CFC-12 is made up of two basic elements, making it easily manufacturable while HFC-134a is much more difficult to manufacture, in turn, making it more expensive to manufacture. Earlier in the development process, chemical engineers said that the replacement chemical were likely to cost up to three times the cost of CFC-12 to produce and might not last as long (Brown, 1989). And while HFC-134a would not affect the ozone layer, it would increase the trapping of solar heat by the atmosphere. As scientists continued to grapple with the ever developing discovery of chlorofluorocarbon substitutes, engineers also considered designing an entirely new refrigeration system without the conventional compression system (Brown, 1990).
While the use of CFCs has greatly benefited technology worldwide, Dr. Manzer of E. I. du Pont de Nemours & Company, stated in 1990 “There's no question that the world will learn to get along without CFC's. The questions that remain have to do with cost - the trade-off costs, as well as the money'’ (Brown, 1990).
As studies continue, the use of HFCs is still being debated. While they’re much better for the environment than CFCs, they still tend to come with a host of environmental issues. An article published in 2015 by the World Resources Institute touches upon various ways the United States can reduce their use of hydrofluorocarbons. Major manufacturers, such as Honeywell and Arkema, are producing alternatives to HFCs, compounds that have less of an effect on the environment. The alternatives tend to include compounds such as carbon dioxide (CO2) and hydrocarbons as well as other synthetic materials. Companies such as Coca-Cola, Pepsi, and Ben and Jerry’s have begun to use coolers with low or zero global warming potential (GWP) HFCs. And although these environmentally friendly compounds may come with higher costs up front, there’s a high probability they will offer net savings over time. The immediate fees include mostly replacement of equipment or the facilitation of vehicle/machinery redesign. Once the Montreal Protocol began phasing out the use of CFCs, a movement of technological development and investment in a new generation of air conditioning and refrigeration systems was spurred, creating both benefits to public health and environmental safety as well as lifetime savings for consumers. The Environmental Protection Agency even found that most products did not cost more than their predecessors, and some machinery was actually cheaper to maintain (Igusky).
Ultimately, it comes down to the sacrifices the population is willing to make. While it may take time and money to replace the existing systems with more environmentally sound machinery, it could ultimately save consumers a considerable amount of money and make the world a safer place to live for its inhabitants.
Works Cited
Brown, Malcolm W. (1989, March 7). In Protecting the Atmosphere, Choices are Costly and Complex. The New York Times. Retrieved from http://www.nytimes.com/1989/03/07/science/in-protecting-the-atmosphere-choices-are-costly-and-complex.html?pagewanted=all.
Brown, Malcolm W. (1990, July 17). Grappling With the Cost of Saving Earth’s Ozone. The New York Times. Retrieved from http://www.nytimes.com/1990/07/17/science/grappling-with-the-cost-of-saving-earth-s-ozone.html?pagewanted=all.
Handwerk, Brian. (2010, May 7). Whatever Happened to the Ozone Hole? The New York Times. Retrieved from https://news.nationalgeographic.com/news/2010/05/100505-science-environment-ozone-hole-25-years/.
Igusky, Kristin. (2015, March 3). Reducing HFCs in the US Would Benefit Consumers and the Climate. The World Resources Institute. Retrieved from http://www.wri.org/blog/2015/03/reducing-hfcs-us-would-benefit-consumers-and-climate.
Le Couteur, Penny and Jay Burreson. (2004). Chlorofluorocarbon Compounds. Napoleon’s Buttons: 17 Molecules That Changed History (pp. 308-329). New York: Jeremy P. Tarcher/Penguin.
