NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Rate constant for the reaction of OH with CH3CCl2F (HCFC-141b) determined by relative rate measurements with CH4 and CH3CCl3Determination of accurate rate constants for OH abstraction is of great importance for the calculation of lifetimes for HCFCs and their impact on the atmosphere. For HCFC-141b there has been some disagreement in the literature for absolute measurements of this rate constant. In the present work rate constant ratios for HCFC-141b were measured at atmospheric pressure in the temperature range of 298-358 K, with CH4 and CH3CCl3 as reference gases. Ozone was photolyzed at 254 nm in the presence of water vapor to produce OH radicals. Relative depletions of 141b and the reference gases were measured by FTIR. Arrhenius expressions for 141b were derived from each reference gas and found to be in good agreement with each other. The combined expression for HCFC-141b which we recommend is 1.4 x 10 exp -12 exp(-1630/T) with k at 298 K being 5.9 x 10 exp -15 cu cm/molec-s. This value is in excellent agreement with the JPL 92-20 recommendation.
Document ID
19930069917
Document Type
Reprint (Version printed in journal)
Authors
Huder, Karin (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Demore, William B. (JPL Pasadena, CA, United States)
Date Acquired
August 16, 2013
Publication Date
August 6, 1993
Publication Information
Publication: Geophysical Research Letters
Volume: 20
Issue: 15
ISSN: 0094-8276
Subject Category
ATOMIC AND MOLECULAR PHYSICS
Distribution Limits
Public
Copyright
Other