Studies on adsorption of crystal violet dye from aqueous solution onto coniferous pinus bark powder (CPBP)

The present study shows that the coniferous pinus bark powder (CPBP) can be used as a potential adsorbent for the removal of crystal violet (basic dye) from aqueous solutions. Experiments were carried out as a function of contact time, concentration, temperature, pH and dosage. The amount of dye uptake was found to vary with increasing initial solution pH and maximum adsorption was observed at pH 8. The equilibrium was attained in 2 h. The amount of dye uptake (mg/g) was found to increase with increase in dye concentration and contact time. The % adsorption was found to decrease with increase in amount of adsorbent. The thermodynamic parameters were also calculated and the positive value of Delta H degrees indicates the endothermic nature of adsorption. The applicability of the three isotherm's model for the present data follows the order: Langmuir>Temkin >Freundlich. The kinetics of crystal violet on to the adsorbent can be described well by pseudo-second order>Elovich>pseudo-first order equation. (c) 2009 Elsevier B.V. All rights reserved.