Historical trend of ozone-depleting substances and hydrofluorocarbon concentrations during 2004–2020 derived from satellite observations and estimates for global emissions

Boosting Catalytic and Anti-fluorination Performance of the Ru/Vanadia–Titania Catalyst for the Oxidative Destruction of Freon by Sulfuric Acid Modification

“…In the last decades, Freon (e.g., chlorofluorocarbons (CFCs)) as the typical F-containing volatile organic compounds (FVOCs) have received significant attention due to the extremely high global warming potential, which are thousands of CO 2 equivalents. , Additionally, CFCs in the atmosphere currently constitute the largest contributor to ozone depletion and have been widely used in various applications (e.g., refrigerants, foaming agents, and insulation materials). − Although the Montreal Protocol has restricted the production of CFCs, the unexpected and persistent leaked low-concentration CFCs in discarded equipment and small-scale production are usually emitted directly to the atmosphere. − CFCs are more difficult to remove than the other non-halogenated volatile organic compounds (VOCs) owing to their high toxicity and unique stability. Catalytic oxidation is considered as a suitable strategy for the complete elimination of low-concentration CFCs under mild conditions, , and it is of paramount significance to investigate the preparation of catalysts with high performance and good durability as well as the underlying catalytic mechanisms.…”

“…In the last decades, Freon (e.g., chlorofluorocarbons (CFCs)) as the typical F-containing volatile organic compounds (FVOCs) have received significant attention due to the extremely high global warming potential, which are thousands of CO 2 equivalents. 1,2 Additionally, CFCs in the atmosphere currently constitute the largest contributor to ozone depletion and have been widely used in various applications (e.g., refrigerants, foaming agents, and insulation materials). 3−5 Although the Montreal Protocol has restricted the production of CFCs, the unexpected and persistent leaked lowconcentration CFCs in discarded equipment and small-scale production are usually emitted directly to the atmosphere.…”

Detection of Atmospheric Hydrofluorocarbon-22 with Ground-Based Remote High-Resolution Fourier Transform Spectroscopy over Hefei and an Estimation of Emissions in the Yangtze River Delta

“…For satellite remote sensing, the limb-viewing infrared Fourier transform spectrometer MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) observed the global HCFC-22 on the Environmental Satellite (ENVISAT) from 2002-2012 [10][11][12]. The Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (ACE-FTS) has been monitoring the global HCFC-22 atmospheric concentration since 2003 [13][14][15][16][17]. Steffen et al (2019) analyzed the HCFC-22 annual trend changes in the tropical region between 7.5-17.5 km in 2004-2018 for ACE-FTS satellite data [17].…”

A Survey on Fluorinated Greenhouse Gases in Taiwan: Emission Trends, Regulatory Strategies, and Abatement Technologies

“…Naturally, the major GHGs include water vapor (H 2 O), carbon dioxide (CO 2 ), methane (CH 4 ), nitrous oxide (N 2 O), and ozone (O 3 ) [1]. Although chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) were phased out under the Montreal Protocol on Substances that Deplete the Ozone Layer [2], the significant emissions of these synthetically chemical alternatives, including hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF 6 ), and nitrogen trifluoride (NF 3 ), have been observed since the 1990s to be consistent with the enhancement of global warming or greenhouse effect due to their radioactively active features with the high global warming potential (GWP) [3][4][5][6]. More importantly, the temperature rise of 1.5 • C on earth could negatively affect the climate system and ecosystem, causing extreme weather events, shifting wildlife populations and habitats, rising sea levels, and increased disease/epidemic risks [7].…”