Fixed-Bed Column Study for Zn (II) Removal from Solution Using Raw Rice Husk

A fixed bed of raw rice husk was used for the removal of Zn (II) from aqueous solution. The material as adopted was found to be an efficient media for the removal of Zn (II) in continuous mode using fixed bed column. Different column design parameters like depth of exchange zone, flow rate and initial concentration were calculated. When conducted with Zn (II) concentration 10 mg.L^-1 and flow rate 10 ml.min^-1 with different bed depths such as 3, 6 and 9 cm, the equilibrium uptake was 3.366, 2.847 and 2.764 mg.g^-1, respectively. The equilibrium uptake decreased from 2.802 to 1.975 mg.g^-1 with increasing of flow rate from 5 to 15 mL.min^-1 and increased from 2.764 to 3.798 mg.g^-1 when initial concentration increased from 10 to 30 mg.L^-1. The dynamics of adsorption process was modeled by bed depth service time (BDST), and indicating the validity of BDST model when applied to the continuous column studies.