MODELING ADSORPTION IN SOLUTE FLOW SIMULATIONS

Abstract

Ionic transport in soils is commonly described by equations representing mass conservation and the rates of ion-soil interactions. The type of adsorption equation used is an important factor in solute flow predictions. Adsorption is most commonly described by either the diffuse double layer (DDL) theory, or approaches based on gas-solid interactions (GSI). Computer simulations, in the form of breakthrough curves for a goethite system, showed that DDL and GSI model predictions were similar. The GSI approach is readily adaptable to adsorption-desorption dynamics and was more convenient than DDL models for the simulation of ionic transport in soils.