Logo image
Back
Fluoroform (CHF3) Production from CF3CHO Photolysis and Implications for the Decomposition of Hydrofluoroolefins and Hydrochlorofluoroolefins in the Atmosphere
Journal article   Peer reviewed

Fluoroform (CHF3) Production from CF3CHO Photolysis and Implications for the Decomposition of Hydrofluoroolefins and Hydrochlorofluoroolefins in the Atmosphere

Joshua D. Thomson, Jyoti S. Campbell, Ethan B. Edwards, Christopher Medcraft, Klaas Nauta, Maria Paula Perez-Pena, Jenny A. Fisher, David L. Osborn, Scott H. Kable and Christopher S. Hansen
Journal of the American Chemical Society, Vol.147(1), pp.33-38
23/12/2024
DOI: https://doi.org/10.1021/jacs.4c11776
PMID: 39714911
Appears in  Recent Faculty of Science and Engineering Publications

Metrics

1 Record Views
13 Times Cited - Web of Science

Abstract

quantum yield lasers photodissociation organic reactions absorption
Hydrofluoroolefins (HFOs) and hydrochlorofluoroolefins (HCFOs) are the leading synthetic replacements for compounds successively banned by the Montreal Protocol and amendments. HFOs and HCFOs readily decompose in the atmosphere to form fluorinated carbonyls, including CF3CHO in yields of up to 100%, which are then photolyzed. A long-standing issue, critical for the transition to safe industrial gases, is whether atmospheric decomposition of CF3CHO yields any quantity of CHF3 (HFC-23), which is one of the most environmentally hazardous greenhouse gases. This comprehensive experimental investigation employs purpose-built photoionization mass spectrometry, Fourier-transform infrared, and microwave spectroscopy techniques and confirms production of CHF3 following excitation at a tropospherically relevant wavelength (lambda = 308 nm) and under atmospheric pressure conditions. Pressure-dependent CHF3 quantum (Phi) and molar (Y) yields are reported from Phi = Y = 0.16 +/- 0.03 under collision-free conditions to Phi = (2.3 +/- 0.3) x 10-4, Y = (1.17 +/- 0.27) x 10-3 at 1 bar N2.

Details

Logo image