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Detailed Mathematical Analysis of Solute Transport in Armfield's Liquid Diffusion Apparatus
Author(s) -
Ramírez Carlos A.
Publication year - 2014
Publication title -
chemical engineering and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.403
H-Index - 81
eISSN - 1521-4125
pISSN - 0930-7516
DOI - 10.1002/ceat.201300261
Subject(s) - thermal diffusivity , mass transfer , aqueous solution , diffusion , chemistry , thermodynamics , constant (computer programming) , mass diffusivity , analytical chemistry (journal) , chromatography , computer science , physics , programming language
A solute's diffusivity is a key property in the design and analysis of mass transfer systems. A simple method to determine such coefficients in aqueous media is Armfield's diffusion apparatus, in which reservoir (donor) and bath (receiver) compartments are separated by a honeycomb array of liquid‐filled cylindrical pores. The solute of interest, i.e., NaCl, diffuses from the reservoir and pores into the bath. The electrical conductivity of the bath solution, which is proportional to the NaCl molarity, is tracked as a function of time at constant temperature. A comprehensive mathematical model is presented which combines simultaneous solute transport in the three compartments, allowing estimation of the aqueous NaCl diffusivity from experimental data. The model improves existing theoretical analyses of such data and can be adapted to study other challenging systems.