Result in Fig. 6 shows the optimum time for the metal beingremoved from the aqueous solution is 60 min, before the amountof metal uptake become constant and no longer dependent on time.At the equilibrium, the amount of Pb, Cu and Cd ions being uptakewere 90.5%, 87.6% and 84.8%, respectively. The data obtained wascalculated by using the equation below (Kavitha & Namasivayam,2007):Pseudo first-order reaction