Abstract

A model for the adsorption of gold from I 2/I - aqueous solutions onto a cellulose acetate (CA)-polyaniline (PANI) porous membrane is presented. The adsorption of gold is represented by an ion-exchange overall reaction in which AuI 2 - ions replace the Cl - ions at the active sites of the polyaniline matrix. The model incorporates the external mass transfer of AuI 2 - from the bulk solution to the membrane surface, followed by the pore diffusion of AuI 2 - to reach the active sites in the membrane. The overall ion-exchange reaction was assumed to achieve local instantaneous equilibrium. Verification of the kinetic model with the experimental data showed that the effective diffusivity of AuI 2 - within the membrane is about 8.3 × 10 -6 cm 2/s. The potential applications of the present formulation are discussed.

Original languageUndefined/Unknown
Pages (from-to)1695-1706
Number of pages12
JournalJournal of Applied Polymer Science
Volume124
Issue number2
DOIs
StatePublished - 2012

Keywords

  • adsorption
  • diffusion
  • membranes
  • modeling

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