Modeling of lead (II) adsorption on sodium hydroxide treated rice husk: Fixed-bed studies

Abstract

The treated rice husk has been evaluated as a sorbent for removing lead (II) from aqueous solutions in fixed-bed studies. In this paper, the effects of flow rate (3 and 9 mL/min), bed depth (0.9, 1.8 and 2.8 cm) and influent lead concentration of (5 and 20 mg/L) on the adsorption capacity of the adsorbent in a fixed-bed column were investigated. The highest adsorption capacity (78 %) on a 20 mg/L Pb (II) solution was achieved within a flow rate of 9 mL/min and a bed depth of 2.8 cm. The experimental data obtained from the adsorption process was correlated with the Thomas, Adams– Bohart and Yoon–Nelson models. The results of the parameters indicated Adams–Bohart model fitted well over the other models.