Chlorofluorocarbon consumption

Regulate a reduction in chlorofluorocarbon consumption of at least 85 percent... 

Production of hydrogen fluoride from reaction of Cap2 with sulfuric acid is the largest user of fluorspar and accounts for approximately 60—65% of total U.S. consumption. The principal uses of hydrogen fluoride are ia the manufacture of aluminum fluoride and synthetic cryoHte for the Hall aluminum process and fluoropolymers and chlorofluorocarbons that are used as refrigerants, solvents, aerosols (qv), and ia plastics. Because of the concern that chlorofluorocarbons cause upper atmosphere ozone depletion, these compounds are being replaced by hydrochlorofluorocarbons and hydrofluorocarbons. 

The Montreal Protocol was initiated in 1987 which required the reduction of production and consumption of chlorofluorocarbons. 

The production of chlorofluoro- and hydrochlorofluorocarbons expanded rapidly after 1945, reaching about 1 million tons in 1986 despite a drop in production in the late 1970s, when the United States and several other countries banned the use of chlorofluorocarbons as aerosol propellants In the early 1990s, production and consumption are in decline... 

Measurements of methyl chloroform or 1,1,1-trichloroethane (CH3CCI3) showed that this compound was significantly unsaturated in the equatorial Pacific Ocean (Butler et al., 1991). Loss rates were supported roughly by known hydrolysis rates and the authors calculated that —6% of atmospheric CH3CCI3 is removed by consumption in the oceans. With this exception, most of the chlorofluorocarbons were originally thought to be stable in the water column. 

For their physical properties, high stability and low toxicity, chlorofluorocarbons (CFC s) have found an extensive use, accompanying the development of various industrial fields. About forty years after their discovery in the early thirties [1], the hypothesis was advanced that, because of their stability, these compounds dispersed in the atmosphere arrived in the stratosphere where they caused a series of reactions generating chlorine and leading to an abnormal consumption of the ozone layer [2]. The Protocol of Montreal and its successive amendments have therefore placed limits to the production and the use of CFCs proscribed in industrialized coimtries since 1996 and fi om 2010 in the underdeveloped nations. 

Conventional chlorofluorocarbon (CFG) and hydrofluorocarbon (HFC) consumption can be completely eliminated by using CO2 as a refrigerant. The... 

Chlorofluorocarbons, or CFCs, are substances used in refrigeration, plastic foam production, the electronic industry and many other applications. CFC and related chemicals have been used from 1929 and their World consumption in 1986 is shown in Figure 3. 

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