Equilibrium and kinetic studies of sorption of polycyclic aromatic hydrocarbons from water using rice husk activated carbon

Abstract

The uptake of polycyclic aromatic hydrocarbons (viz., naphthalene, phenanthrene and pyrene) by rice husk activated carbon was comparable to conventional adsorbent, powdered activated carbon and higher than all other agricultural and industrial adsorbents. Polycyclic aromatic hydrocarbons showed similar behaviour regarding kinetics after 24 h. Polycyclic aromatic hydrocarbon removal follow the order naphthalene < phenanthrene < pyrene. Molecular weight and solubility play vital role in the adsorption of polycyclic aromatic hydrocarbon on rice husk activated carbon. The results pointed to the occurrence of intraparticle mechanism in all cases. The isotherm models which best represented the data obtained were Freundlich for naphthalene, Redlich-Peterson for phenanthrene and Langmuir for pyrene. These observations suggest that rice husk activated carbon have great potential as biosorbents to remove polycyclic aromatic hydrocarbons from water.