Fluorine in annual revenue. Due to the danger from direct hydrocarbon–fluorine reactions above −150 °C (−240 °F), industrial fluorocarbon production is indirect, mostly through halogen exchange reactions such as Swarts fluorination, in which chlorocarbon chlorines are substituted for fluorines by hydrogen fluoride under catalysts. Electrochemical fluorination subjects hydrocarbons to electrolysis in hydrogen fluoride, and the Fowler process treats them with solid fluorine carriers like cobalt trifluoride. Halogenated refrigerants, termed Freons in informal contexts, are identified by R-numbers that denote the amount of fluorine, chlorine, carbon, and hydrogen present. Chlorofluorocarbons (CFCs) like R-11, R-12, and R-114 once dominated organofluorines, peaking in production
Bromine production in the United States rail access, and difficult highway access, and was shut down in 1945. Dow found a better permanent location at Freeport, Texas, where a seawater extraction plant started in 1940, and a second in 1943. The Freeport plants recovered magnesium, sodium compounds, and chlorine, in addition to the bromine. The Freeport chemical operations are still active, but they stopped extracting bromine in 1969. Brine mining Bromine production in the United States Bromine production in the United States of 225,000 tonnes in 2013 made that country the second-largest producer of bromine, after Israel. The US supplied 29 percent of world production. Since