where qt is the adsorption capacity at time t (mg/g), k 1 is the
first-order reaction rate constant (L/min) and k 2 represents the
second-order reaction rate constant (g/mg.min). The plots of
pseudo-first-order and pseudo-second-order models are
illustrated in Figs. 6 and 7, respectively. A comparison of the
reaction rate constants and R2 values estimated from the
pseudo-first-order and second-order equations is presented in
Table II.