Equilibrium sorption of anionic dye from aqueous solution by palm kernel fibre as sorbent

Palm kernel fibre was investigated for its ability to perform as a suitable sorbent for anionic dye from aqueous solution. The effect of sorbent dose and temperature was investigated using a batch sorption technique. The results revealed the potential of palm kernel fibre, an agricultural waste, as a low-cost sorbent for the anionic dye examined. The isotherm data were closely fitted to the Langmuir equation and the dye sorption capacity of palm kernel fibre increased as the sorbent dose decreased. Maximum saturated monolayer sorption capacity of palm kernel fibre for 4-bromoaniline-azo-1,8-dihydronaphthalene-3,6-disodiumsulphate was 38.6 mg/g. Thermodynamic parameters such as change in the free energy, the enthalpy, and the entropy were also evaluated. In addition, relationships between sorbent dose and Langmuir constants were developed and are presented. © 2006 Elsevier Ltd. All rights reserved.