Using diffusion measurements to determine pore-size distributions in porous materials

Conference · Tue Jan 01 04:00:00 EST 1980 · AIChE Pap.; (United States)

OSTI ID:6469310

Brown, L F; Travis, B J

The internal structure of the porous solid was modeled as nonintersecting cylindrical pores of random directions. A relationship was derived for the flux as a function of pressure in which the flux is a functional of the pore size distribution. The resulting Fredholm integral equation of the first kind was solved for the diffusion region between Knudsen and bulk diffusion, which can be measured by Wicke-Kallenbach experiments. Calculations of pore size distributions of hypothetical materials with ideal simple or bimodal pore distributions for 0.1-2.0 MPa and 0.1-30.0 MPa showed the validity of the method. The method also predicted the diffusion as a function of pressure in Girdler G-3B porous catalyst, for which Wicke-Kallenbach data were available, but calculated results deviated for the pore size distribution based on available mercury porosimeter data for the same catalyst.

• Research Organization: Los Alamos Scientific Lab.
• OSTI ID: 6469310
• Report Number(s): CONF-800610-
• Conference Information: Journal Name: AIChE Pap.; (United States) Journal Volume: 1A
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360602 -- Other Materials-- Structure & Phase Studies
CATALYSTS
CRYSTAL STRUCTURE
DIFFUSION
EQUATIONS
FREDHOLM EQUATION
INTEGRAL EQUATIONS
MATERIALS
MATHEMATICAL MODELS
MEASURING INSTRUMENTS
METALLURGICAL FLUX
MICROSTRUCTURE
POROSIMETERS
POROSITY
POROUS MATERIALS
PRESSURE DEPENDENCE
TESTING
VALIDATION