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An assessment of potential degradation products in the gas-phase reactions of alternative fluorocarbons in the troposphere
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Niki, Hiromi |
| Copyright Year | 1990 |
| Description | Tropospheric chemical transformations of alternative hydrofluorocarbons (HCF's) and hydrochlorofluorocarbons (HCFC's) are governed by hydroxyl radical initiated oxidation processes, which are likely to be analogous to those known for alkanes and chloroalkanes. A schematic diagram is used to illustrate plausible reaction mechanisms for their atmospheric degradation, where R, R', and R'' denote the F- and/or Cl-substituted alkyl groups derived from HCF's and HCFC's subsequent th the initial H atom abstraction by HO radicals. At present, virtually no kinetic data exist for the majority of these reactions, particularly for those involving RO. Potential degradation intermediates and final products include a large variety of fluorine- and/or chlorine-containing carbonyls, acids, peroxy acids, alcohols, hydrogen peroxides, nitrates and peroxy nitrates, as summarized in the attached table. Probably atmospheric lifetimes of these compounds were also estimated. For some carbonyl and nitrate products shown in this table, there seem to be no significant gas-phase removal mechanisms. Further chemical kinetics and photochemical data are needed to quantitatively assess the atmospheric fate of HCF's and HCFC's, and of the degradation products postulated in this report. |
| File Size | 704809 |
| Page Count | 16 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19920006225 |
| Archival Resource Key | ark:/13960/t4cp2141n |
| Language | English |
| Publisher Date | 1990-01-01 |
| Access Restriction | Open |
| Subject Keyword | Environment Pollution Carbonyl Compounds Chlorofluorocarbons Hydrogen Peroxide Vapor Phases Troposphere Chemical Reactions Nitrates Fluorocarbons Alcohols Reaction Products Degradation Atmospheric Composition Atmospheric Chemistry Reaction Kinetics Hydroxyl Radicals Air Pollution Oxidation Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
