Q835. What factors influenced the trend in emissions for fluorinated chemicals production?
A835. Reported emissions from the Fluorinated Chemicals Production sector decreased from 17.4 million metric tons (MMT) CO2e in 2011 to 8.11 MMT CO2e in 2018, a decrease of 53%. This long-term downward trend was driven primarily by increases in voluntary emission controls at facilities (e.g., use of destruction devices) but also by changes in the types and quantities of fluorinated gases produced. The fluctuations seen between 2016 and 2018 were driven by fluctuations in production of chlorodifluoromethane (HCFC-22), which is associated with emissions of trifluoromethane (HFC-23).  Since 2012, emissions from HCFC-22 production and HFC-23 destruction have varied between a low of 2.8 MMT CO2e in 2016 and a high of 5.2 MMT CO2e in 2017.  Emissions from production of other fluorochemicals have varied between a high of 9.3 MMT CO2e in 2013 and a low of 4.8 MMT CO2e in 2016, with emissions holding steady since then.
 Trifluoromethane (HFC-23 or CHF3) is generated as a byproduct during the manufacture of chlorodifluoromethane (HCFC-22). HCFC-22 is produced by the reaction of chloroform (CHCl3) and hydrogen fluoride (HF) in the presence of a catalyst, SbCl5. The HFC-23 generated may be released to the atmosphere, recaptured for use in a limited number of applications, or destroyed.
 Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2017. U.S. Environmental Protection Agency. April 11, 2019. EPA 430-R-18-003. Available at https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks-1990-2017.