Kinetic study on lead (II) ion removal by adsorption onto peanut hull ash

This paper investigates the adsorption of lead (II) ion from aqueous solution by using peanut hull ash (PHA). The PHA was found to be effective in removing lead (II) ion from aqueous solution. Experimental results indicated both the rate of removal and the removal at equilibrium were increased with decreasing PHA dosage or increasing initial lead concentration. pH, stroke speed, and adsorption temperature, however, were found to have no effect on the rate of removal and removal at equilibrium for the high PHA dosage, 3.0 g/L. High value of pH, however, might increase the removal for the low PHA dosage, 0.2 g/L. The overall adsorption process was found to be controlled by the physisorption step and suitably interpreted by a pseudo-second-order rate equation. An empirical relationship between the removal of lead ion and adsorption time for high PHA dosage was also determined.