Model identification and diffusion coefficients determination of glucose and malic acid in calcium alginate membranes

Abstract

Cell-free and cell-occupied calcium alginate membranes were placed in a plate diffusion cell. The measurements of the diffusion coefficients for glucose and malic acid were performed for each isolated solute, for cocurrent diffusion and with simultaneous CO2 evolution. The results indicate that neither CO2 release nor solute concentration or cocurrent diffusion affect the diffusion coefficients of either solute. The presence of cells is the main factor responsible for the decrease in solute transport across alginate membranes. The mass transfer mechanism in cell-occupied membranes is better characterized by the random pore model.