Removal of Torque Blue Dye from Aqueous Solution by Kail Sawdust

Kail sawdust (Pinus wallichiana) was used for the removal of Torque Blue dye (textile dye) from water using a batch adsorption technique. The effect of initial dye concentration, adsorbent size (particle size) and dosage, pH and temperature on the removal of dye from water was studied to understand the process of adsorption and the kinetics of adsorption process. It was found that maximum (98.7%) adsorption occurred at an adsorbent dosage of 0.5 gm/100 ml dye solution with a particle size of 75 μm in 15 mg/L dye concentration at 37°C temperature and 7.5 pH. The Langmuir adsorption isotherm model fitted the data well. The rate of adsorption was better fitted by pseudo first order kinetics. The values of thermodynamic parameters (ΔG°, ΔH° and ΔS°) indicated that adsorption was spontaneous and exothermic. The surface morphology and the functional groups on the adsorbent surface were characterised by SEM and FTIR spectroscopic techniques.