The regeneration with sodium hydroxide of fixed-bed adsorbers saturated with single and binary mixtures of phenol and m-cresol has been investigated by performing a set of desorption experiments. The process simulation is accomplished by the development of a mathematical model considering the effects of axial dispersion in the liquid phase, film diffusion, intraparticle mass transfer, and reaction between sodium hydroxide and phenol/m-cresol species. The particle equations were discretized by orthogonal collocation on finite elements, and the resulting ordinary differential equations together with the mass balance equations were numerically solved with the PDECOL package. The effects of the flow rate of the regenerant and bed initial conditions on single and binary experiments are addressed. Experimental data show that regeneration with sodium hydroxide is efficient and faster than conventional desorption with a solvent.