Chlorine initiated oxidation studies of hydrochlorofluorocarbons: Results for HCFC-123 (CF3CHCl2) and HCFC-141b (CFCl2CH3)

✍ Scribed by E. O. Edney; B. W. Gay; D. J. Driscoll

• Publisher: Springer Netherlands
• Year: 1991
• Tongue: English
• Weight: 841 KB
• Volume: 12
• Category: Article
• ISSN: 0167-7764
• DOI: 10.1007/bf00115774

✦ Synopsis

Oxidation reactions of the proposed CFC substitutes HCFC-123 (CF,CHCI,) and HCFC-141b (CFCl&H,) have been studied in the laboratory using long-path Fourier transform infrared spectroscopy. The air oxidation of the HCFCs was initiated by the photolysis of Cl, forming Cl atoms that abstract H atoms from the HCFC. CF,C(O)Cl was the only carbon containing compound observed in the infrared spectrum of the products of the HCFC-123/C12 irradiations and its yield was approximately one. The product data are consistent with formation of CF,C(O)Cl by Cl elimination of the intermediate halogenated alkoxy radical CF,CC120. The Cl-initiated oxidation of HCFC-141b led to the formation of CO and C(O)FCI. The product data are consistent with a 1 : 1 relationship between C(O)FCl formed and HCFC-141b reacted. Product data were compatible with both decomposition by cleavage of the C-C bond of the radical CFCl,CH,O leading to the prompt generation of C(O)FCI and reaction of the radical with O2 forming the two carbon halogenated aldehyde CFCI,CH(O), which in the presence of CI was likely oxidized to C(O)FCl. An approximate method was developed in which the ratio was extracted from analysis of the time evolution of HCFC14lb. C(O)FCI, and CO. The data suggest that the contributions are comparable.