Premium
Adsorption rate studies—significance of pore diffusion
Author(s) -
Masamune Shinobu,
Smith J. M.
Publication year - 1964
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.690100222
Subject(s) - adsorption , thermal diffusivity , diffusion , surface diffusion , chemistry , nitrogen , radius , thermodynamics , porosity , helium , critical radius , chemical engineering , organic chemistry , physics , geometry , computer security , mathematics , curvature , computer science , engineering
Adsorption rates were measured by a transcient method for nitrogen on beds of porous Vycor glass particles. Nitrogen was adsorbed, from a low concentration in helium, at liquid nitrogen temperature. Equations are presented for the concentration as a function of time and position in the bed, based upon surface adsorption, pore diffusion, or external diffusion controlling the overall process. Analysis of the data with these results indicates that the surface adsorption is a very rapid process and that pore processes determine the rate for particles larger than 0.01 cm. in radius. The effective pore diffusivity was determined to be 0.04 sq. cm./sec. The predominant contribution to the diffusivity is a surface mechanism rather than diffusion in the gas within the pores.