Chlorofluorocarburo

Chlorofluorocarburos (CFC) e hydrochlorofluorocarburos (HCFC) son hydrocarburos halogenate que contine carbon (C), hydrogeno (H), chloro e (Cl) e fluor (F). Son volatile derivates de methano, ethano o propano.

Le exemplo le plus consuete es le dichlorodifluoromethano (R-12), alsi appellate Fréon. Essava usate como refrigerante fuido in refrigeratores e alsi como aerosol propulsor, extinctor de incendios gasose, o solvente.

Iste compositos son nocive pro le ozonosphera (strato de ozone) e ha un effecto conservatorio multe importante. In consquentia, lor fabrication ha essite progressivemente abandonate, conformemente al . Son reimplaciate per altere productos como hydrofluorocarburos (HFC) o hydrofluoroolefinas (HFO) (includente R-410A, le R-134a e R-1234yf).

 Productos 
Freones continente bromo son notate con 4 nummeros. Isomeres, que son consuete pro ethano e propano derivatos, son distinguite per literas post numeros:

 Principal CFC Systematic nomine Usual nomine, code Ebullition (°C) Formula Trichlorofluoromethano Freon-11, R-11, CFC-11 23.77 CCl3F Dichlorodifluoromethano Freon-12, R-12, CFC-12 −29.8 CCl2F2 Chlorotrifluoromethano Freon-13, R-13, CFC-13 −81 CClF3 Dichlorofluoromethano R-21, HCFC-21 8.9 CHCl2F Chlorodifluoromethano R-22, HCFC-22 −40.8 CHClF2 Chlorofluoromethano Freon 31, R-31, HCFC-31 −9.1 CH2ClF Bromochlorodifluoromethano BCF, Halon 1211, H-1211, Freon 12B1 −3.7 CBrClF2 1,1,2-Trichloro-1,2,2-trifluoroethano Freon 113, R-113, CFC-113, 1,1,2-Trichlorotrifluoroethane 47.7 Cl2FC-CClF2 1,1,1-Trichloro-2,2,2-trifluoroethano Freon 113a, R-113a, CFC-113a 45.9 Cl3C-CF3 1,2-Dichloro-1,1,2,2-tetrafluoroethano Freon 114, R-114, CFC-114, Dichlorotetrafluoroethano 3.8 ClF2C-CClF21,1-Dichloro-1,2,2,2-tetrafluoroethanoCFC-114a, R-114a3.4Cl2FC-CF3 1-Chloro-1,1,2,2,2-pentafluoroethane Freon 115, R-115, CFC-115, Chloropentafluoroethano −38 ClF2C-CF3 2-Chloro-1,1,1,2-tetrafluoroethano R-124, HCFC-124 −12 CHFClCF3 1,1-Dichloro-1-fluoroethano R-141b, HCFC-141b 32 Cl2FC-CH3 1-Chloro-1,1-difluoroethano R-142b, HCFC-142b −9.2 ClF2C-CH3 Tetrachloro-1,2-difluoroethano Freon 112, R-112, CFC-112 91.5 CCl2FCCl2F Tetrachloro-1,1-difluoroethano Freon 112a, R-112a, CFC-112a 91.5 CClF2CCl3 1,1,2-Trichlorotrifluoroethano Freon 113, R-113, CFC-113 48 CCl2FCClF2 1-bromo-2-chloro-1,1,2-trifluoroethano Halon 2311a 51.7 CHClFCBrF2 2-bromo-2-chloro-1,1,1-trifluoroethano Halon 2311 50.2 CF3CHBrCl 1,1-Dichloro-2,2,3,3,3-pentafluoropropano R-225ca, HCFC-225ca 51 CF3CF2CHCl2 1,3-Dichloro-1,2,2,3,3-pentafluoropropano R-225cb, HCFC-225cb 56 CClF2CF2CHClF

 Reimplaciamente 

 Applications and replacements for CFCs Application Previe CFC Reimplacimento Refrigeration CFC-12 (CCl2F2); CFC-11(CCl3F); CFC-13(CClF3); HCFC-22 (CHClF2); CFC-113 (Cl2FCCClF2); CFC-114 (CClF2CClF2); CFC-115 (CF3CClF2); HFC-23 (CHF3); HFC-134a (CF3CFH2); HFC-507 (a 1:1 azeotropic mixture of HFC 125 (CF3 CHF2) and HFC-143a (CF3CH3)); HFC 410 (a 1:1 azeotropic mixture of HFC-32 (CF2H2) and HFC-125 (CF3CF2H)) Propulsores in medicinal aerosoles CFC-114 (CClF2CClF2) HFC-134a (CF3CFH2); HFC-227ea (CF3CHFCF3) Sufflante agentes pro spumas CFC-11 (CCl3F); CFC 113 (Cl2FCCClF2); HCFC-141b (CCl2FCH3) HFC-245fa (CF3CH2CHF2); HFC-365 mfc (CF3CH2CF2CH3) Solventes, disgrassante agentes, nettamento agentes CFC-11 (CCl3F); CFC-113 (CCl2FCClF2) HCFC-225cb (C3HCl2F5) 

 Presentia in atmosphera 
Le CFC ha essite initialemente reimplaciate per hydrochlorofluorocarburos (HCFC), principalemente pro refrigeration e le sufflaje de insulante spuma, quando non nocive alternativas non esseva trovate.

Hodie, gratias al Montreal protocollo, le atmospheric quantitate de HCFC comencia a decrescer.

Categoria:Organohaluros