Hydrofluorocarbon
Synthetic organic compounds
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Related on Lably
Through Ozone layer, Montreal Protocol and Climate change
While HFCs do not degrade the ozone layer to the same degree as the compounds they replace, they still contribute to global warming. For example, trifluoromethane (CHF3 or R-23) has 11,700 times the warming potential of carbon dioxide. HFC atmospheric concentrations and contribution to anthropogenic greenhouse gas emissions are rapidly increasing – consumption rose from near zero in 1990 to 1.2 billion tons of carbon dioxide equivalent in 2010 – causing international concern about their radiative forcing.
Chemistry
Fluorocarbons with few C–F bonds behave similarly to the parent hydrocarbons, but their reactivity can be altered significantly. For example, both uracil and 5-fluorouracil are colourless, high-melting crystalline solids, but the latter is a potent anti-cancer drug. The use of the C–F bond in pharmaceuticals is predicated on this altered reactivity. Several drugs and agrochemicals contain only one fluorine center or one trifluoromethyl group.
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Environmental regulation
Unlike other greenhouse gases in the Paris Agreement, hydrofluorocarbons are included in other international negotiations.
In September 2016, the New York Declaration on Forests urged a global reduction in the use of HFCs. On 15 October 2016, due to these chemicals' contribution to climate change, negotiators from 197 nations meeting at a summit of the United Nations Environment Programme in Kigali, Rwanda reached a legally-binding accord (the Kigali Amendment) to phase down HFCs in an amendment to the Montreal Protocol. As of February 2020, 16 U.S. states ban or are phasing down HFCs.
COVID-19 relief legislation, which included a measure that would require chemical manufacturers to phase down the production and use of HFCs, was passed by the United States House of Representatives and United States Senate on 21 December 2020. The U.S. Environmental Protection Agency signed a final rule phasing down HFCs on 23 September 2021. President Trump has announced a rollback of regulations on super pollutants, specifically targeting potent greenhouse gases used in refrigeration and air conditioning in May 2026.