Removal of Harmful Textile Dye Congo Red from Aqueous Solution Using Chitosan and Chitosan Beads Modified with CTAB

摘要

Color is an important aspect of human life. Textile industries are the major consumers of dye stuffs. During coloration process, 10 to 15 percent of the dyes will be lost and this will be discharged with the effluents coming from textile industries. These are very difficult to degrade and they may degrade to form products that are highly toxic to human. Today, methods such as coagulation, flocculation, activated carbon adsorption, etc. are available for the removal of dyes. These are all quite expensive and difficult to degrade. Chitosan is a natural hetero polymer derived from chitin. Chitosan has proved to be effective in removing hazardous compounds from environment due to its multiple functional groups. It is available as flakes and powder. In the present work, chitosan beads were prepared and modified with a cationic surfactant CTAB for the removal of dye Congo Red. Batch experiments were conducted to study the effect of CTAB concentration, contact time, agitation speed, adsorbent dosage, initial dye concentration and pH. Batch equilibrium data were analyzed using Langmuir and Freundlich isotherm. Bach kinetic data were analyzed using Pseudo first order kinetic model and pseudo second order kinetic model.