A simple and interesting method is presented for analyzing the effect of adsorbent mass on the rate of adsorption process. In this approach, a graphical method is applied for determination the adsorbent mass order in the rate equation. The proposed analysis is according to the plot of the normalized adsorbed amount q(c)-q/q(c), versus the normalized time scale t[m](n). In comparison with the limited available methods for describing the adsorbent dosage effect on the adsorption rate, this method needs fewer experiments. The classical adsorption kinetic models were extended by considering mass of adsorbent which provides unique rate coefficient for all experiments. (C) 2017 Elsevier B.V. All rights reserved.