Globally, HFC-23 emissions calculated from atmospheric measurements are historically at their highest level in 2018, in contrast to reported emissions as by-product primarily from HCFC-22 production which were much lower, according to a recent paper . China and India set out ambitious programmes to reduce HFC-23 emissions. The paper concludes that the discrepancy between expected and observation-inferred emissions, makes it likely that the reported reductions have not fully materialized or there may be substantial unreported production of HCFC-22, resulting in unaccounted-for HFC-23 by-product emissions.
From this year (1 January 2020) the Montreal Protocol Article 2J (the Kigali Amendment) requires that HFC-23 (an ultra-high GWP HFC) from HCFC-22 production is destroyed to the extent practicable. HCFC-22 is produced as a feedstock for fluropolymer manufacture. The EU reports its emissions of HFC-23, as part of its Annual greenhouse gas inventory submission to the unfccc . From this, in 2017 the EU share of global HFC-23 emissions, reported in the paper, was about 0.2%. The EU reported over 98% reduction in emissions in 2017 compared to 1990.
Complimentary to the Kigali Amendment, the F-gas Regulation 517/2014 in Article 7 states that the placing on the market of HFCs and HFOs shall be prohibited unless, where relevant, that trifluoromethane, produced as a by-product during the manufacturing process, including during the manufacturing of feedstocks for their production, has been destroyed or recovered for subsequent use, in line with best available techniques.
1 Increase in global emissions of HFC-23 despite near-total expected reductions, Nature Communications https://doi.org/10.1038/s41467-019-13899-4
2 EEA/PUBL/2019/051 Annual European Union greenhouse gas inventory 1990–2017 and inventory report 2019 Submission under the United Nations Framework Convention on Climate Change and the Kyoto Protocol page 469