ABSTRACT Hydrofluorocarbons (HFCs) are one of the alternatives to ozone-depleting chlorofluorocarbons (CFCs) in refrigeration, air conditioning and foam blowing. But their high global warming potentials (GWPs) have given rise to the concern that increased use and direct emissions of HFCs could have a significant impact on climate change. Some other CFC alternatives such as fluorinated alcohols (FAs) have been proposed in many industrial applications. The tropospheric photooxidation of FAs yields fluorinated aldehydes as secondary pollutants. To evaluate the tropospheric persistence of these species it is necessary to determine the rate coefficients of the main removal pathways in the gas-phase, namely UV photolysis and reaction with hydroxyl (OH) (J and kOH, respectively). The tropospheric lifetimes (t) of a species can be calculated from J and kOH. In this article, the gas-phase kinetics of OH radicals with CF3CH2CH2OH, CF3(CH2)2CH2OH, CF3CF2CH2OH, CHF2CF2CH2OH, CF3CH2CHO, CF3(CH2)2CHO and CF3CF2CHO recently reported by our research group, as a function of temperature (263‑359 K) and pressure (40‑215 Torr of He), is reviewed. The determination of kOH as a function of temperature was performed by Pulsed Laser Photolysis – Laser Induced Fluorescence (PLP – LIF). Furthermore, a photochemical study of the fluorinated compounds at 308 nm (in the actinic region) is also reviewed here, including the determination of the UV absorption cross sections (sl) between 200 and 370 nm and photodissociation quantum yields by PLP at 308 nm coupled to Fourier transform Infrared (FTIR) spectroscopy (Fl = 308nm). The formation of the photodegradation products initiated by absorption of UV radiation at 308 nm in a simulated clean atmosphere is also reviewed. It can be concluded that hydrofluorinated alcohols (HFAs) are suitable for replacing HFCs, since they are short‑lived compounds that do not contribute to the Earth’s global warming. The degradation of these fluorocompounds is not expected to significantly contribute to air pollution in free-NOx atmospheres.
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