NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Surface reaction and pore diffusion in flow-tube reactorsThe interaction of gas diffusion with surface reaction in porous solids is discussed and applied specifically to heterogeneous rate measurements in flow-tube reactors. External diffusion to the outer surface of a reactive solid, internal diffusion within the pores, surface reaction, and laminar flow are considered. A procedure is developed to correct observed surface rate constants for the interaction of these processes. Measured surface areas and bulk densities are used to construct a semiempirical model for porous diffusion in vapor-formed HNO3-H2O ices which are used to simulate polar stratospheric cloud surfaces. The model is tested experimentally by varying the thickness of these ices from about 15 to 120 microns. The results are consistent with the model predictions and show that the HNO3-H2O ices used are highly porous, and the internal surface must be considered in calculating kinetic parameters from observed loss rates. The best fit of the data yields a tortuosity factor of 3.3 +/-1.1 for the ice substrates.
Document ID
19920037232
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Keyser, Leon F.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Moore, Steven B.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Leu, Ming-Taun
(JPL Pasadena, CA, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1991
Publication Information
Publication: Journal of Physical Chemistry
Volume: 95
Issue: 14, 1
ISSN: 0022-3654
Subject Category
Inorganic And Physical Chemistry
Accession Number
92A19856
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available