A numerical model describing transport of multiple species and chemical reactions during
electrokinetic treatment is presented. The transport mechanisms included in the model were
electromigration and electroosmosis. The chemical reactions taken into account were water
electrolysis at the electrodes, aqueous species complexation, precipitation, and dissolution.
The model was applied to simulate experimental data from an acid-enhanced electrokinetic
treatment of a Pb-contaminated calcareous soil. The kinetics of the main pH buffering process
(i.e., calcite dissolution) was taken into account and its time-dependent behavior was described
by a rate law. The influence of kinetics was evaluated by comparing the results from a set of
simulations in which calcite dissolution was implemented considering thermodynamic
equilibrium and another set in which the same reaction was described by the rate law. The results
show that the prediction capability of the model significantly improves when the kinetic rate is
taken into account.
