Chlorodifluoromethane HCFC

Chlorofluorocarbon-blown foam blocks are used to insulate the walls and roofs of some buildings, thus reducing heat losses and helping to conserve fossil fuels. In this area, polyurethane foam competes with polystyrene foam, which until recently was blown with dichlorodifluoromethane (CFC 12) but is now blown with a mixture of chlorodifluoromethane (HCFC 22) and 1 -chloro-l,l-difluoroethane (HCFC 142b). 

Midgley, P. M and A. McCulloch, "Estimated National Releases to the Atmosphere of Chlorodifluoromethane (HCFC-22) during 1990, Atmos. Environ., 31, 809-811 (1997). 

Reported aqueous solubilities and vapor pressures of chlorodifluoromethane (HCFC-22) at various temperatures... 

The decomposition of chlorodifluoromethane (HCFC-22) using gold supported on sulfated Ti02/Zr02 proceeded as follows 117... 

Aucott M. L., McCulloch A., Graedel T. E., Midgley P., and Li Y.-F. (1999) Anthropogenic emissions of trichlorometh-ane (chloroform, CHCI3 and chlorodifluoromethane (HCFC-22) reactive chlorine emissions inventory. J. Geophys. Res. 104, 8405-8415. 

Chlorodifluoromethane (HCFC 22 R 22) 96.4 48.5 Combustible under specific conditions... 

Miller B., Huang J., Weiss R., Prinn R., Fraser P. (1998) Atmospheric trend and lifetime of chlorodifluoromethane (HCFC-22) and the global tropospheric OH concentration. Geophys. Res. 103, 13237—48. 

HCFC21. See Dichlorofluoromethane HCFC 22. See Chlorodifluoromethane HCFC 23. See Trifluoromethane HCFC 123 HCFC f23. See Dichlorotrifluoroethane HCFC 141b HCFC f4fb. See Dichlorofluoroethane... 

HF CHCl2F-(-HCl (Dichlorofluoromethane HCFC-21) +2HF- CHC1F2+2HC1 (Chlorodifluoromethane HCFC-22) -t3HF->CHF3 + 3HCl (Trifluoromethane HFC-23)... 

CFCs were rapidly banned under the Montreal Protocol (1987) - in fact the manufacture of CFjClg is now banned - and substitutes were introduced in the early 1990s, such as hydrocarbons like butane or less stable CFCs like chlorodifluoromethane (HCFC-22 or R-22). 

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