A generalized nonlinear driving force (NLDF) approximation of intraparticle mass transfer rate for nonlinear isotherm systems with macropore diffusion control is presented. The obtained expression is compared with the solutions of the Fickian diffusion and adsorption model and excellent accuracy over the entire time (fractional uptake) domain and for all values of the Freundlich exponent (adopted as the isotherm nonlinearity measure) is demonstrated. The high accuracy of the model is further demonstrated by comparison with experimental data. The presented methodology for the derivation of driving force approximations is shown to be a useful alternative to the methodology based on intraparticle concentration profile approximations.