Pore-scale study of dynamic adsorption of a water-soluble catalyst during drainage displacement in porous media using lattice Boltzmann simulations

This paper presents the first systematic pore-scale study of the dynamic adsorption of a water-soluble catalyst during two-phase flows of immiscible fluids (water and oil) in porous media. The results of this paper are based on mathematical modeling in two-dimensional synthetic porous structures using the lattice Boltzmann simulations for two-phase flow and convective-diffusive transport of catalyst dissolved in a water that cannot penetrate the oil. The results showed that an increase in oil viscosity tends to a decrease in the maximum adsorbed amount of catalyst measured in a quasi-stationary state. An increase in capillary number, on the contrary, promotes an increase in the adsorbed amount. In this paper, for the first time, we have characterized the dynamic adsorption regimes versus the adsorption rate constant and capillary number. At a low adsorption rate, the adsorbed amount is determined by the duration of the reaction between the catalyst and the adsorbent particles, while at a high adsorption rate, the adsorbed amount is controlled by the maximum adsorption value. In addition, it has been established that a prediction accuracy of the adsorbed amount deteriorates significantly with decreasing capillary number.