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Diffusion processes in multicomponent mixtures can behave
in quite a different way than in binary mixtures, where the General Fick’s
Law is valid. In multicomponent mixtures, the diffusive flux of one component
can be influence not only by the concentration gradient of that component,
but also by all the other concentration gradients. Although in many cases
these effects are negligible under a practical point of view (Cussler,
1976), there are some other cases where it is important to take them into
account, as in film drying processes (Pourdarvish, 2005). Some theories
are available to predict all the diffusion coefficients needed to describe
a multicomponent process based on the thermodynamics of the system and
the transport properties of the binary case. Nevertheless no experimental
values for those coefficients have been reported in the literature, since
no experimental technique has been successfully applied to multicomponent
processes. In this work, we propose using the inverse gas chromatography
(IGC) as a base to experimentally determine these diffusion coefficients.
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