Computational Study of Hydrofluoroolefins (HFO’s): Reactivity with CI/HO Radicals and Ozone in the Troposphere

In 1974, scientists linked chloroflueorocarbons (CFC's) to the depletion of the stratospheric ozone layer. As a result, researchers have sought to find alternate refrigerants and propellants with little or no ozone depletion potential (ODP).

Hydrofluoroolefins (HFO’S) are promising non-chlorine containing CFC replacements with appear to have relatively short atmospheric lifetimes, near zero to zero ODP's, and limited transport to the stratosphere. However, to date researchers have only conducted a limited number of HFO degradation product studies.

The goal of this Edgren project was to identify likely degradation pathways of HFO's via their reaction with their prevalent species in the troposphere (HO, Cl, and ozone). Stoffregen and Mojeske used computational chemistry techniques to model HFO reaction with HO, Cl, and ozone in order to determine whether HFO's are possible contributors to the bio accumulation of perfluorinated acids in fish and mammals and in surface water.