The adsorption of crystal violet (CV) dye onto kola nut husk based activated carbon (KPAC) was carried out in this work. The effects of various reaction parameters such as contact time, initial pH, initial CV concentration, adsorbent dosage and solution temperature were investigated. The sorption of CV dye on
KPAC was found to increase with increase in initial dye concentration, passed through a maximum as function of pH (at pH 8), and decreased with increase in temperature. The adsorption equilibrium data were best represented with the Langmuir model. Kinetic studies revealed that the adsorption data fit well to the pseudo-second-order model with high correlation coefficient. The apparent energy of adsorption (E) of CV using KPAC is 11.323kJmol-1. The Thermodynamic properties showed that adsorption of CV onto KPAC was exothermic, spontaneous and feasible with a decrease in the degree of freedom of the adsorbed species in the
temperature range 303-333K. The KPAC can be used as effective and low cost adsorbent for the removal of CV dye from aqueous solution.