Fixed bed column study for the removal of crystal violet (C. I. Basic Violet 3) dye from aquatic environment by surfactant-modified alumina

The fixed bed column study was undertaken for the removal of crystal violet (CV), also known as Basic Violet 3, a well-known cationic dye from wastewater using surfactant-modified alumina (SMA) as an adsorbing media. The SMA was found to be a very efficient media for the removal of dye from wastewater. The column with 2 cm diameter, different bed heights such as 10, 20 and 30 cm could treat 3.58 l, 7.94 l and 12.51 l, respectively, of CV bearing wastewater with CV concentration 200 mg/l and flow rate 8.5 ml/min. The adsorption bed was exhausted within a very short time (∼1.5 h) after the breakthrough occurred. This indicated that the adsorption zone was almost saturated at the time of exhaustion. Different column design parameters like depth of exchange zone, time required for exchange zone to move its own height, adsorption rate, adsorption capacity etc. were calculated. Effect of flow rate and initial concentration was studied. Theoretical breakthrough curve was drawn from the batch isotherm data and was compared with experimental breakthrough curve. Desorption of CV from the SMA surface was possible using 1 M sodium hydroxide solution, rectified spirit and acetone.