Some New Three-Level of Design Experiments for the Determination of Adsorption Equilibrium of a Basic Dye on Chitosan

The adsorption of basic dye on chitosan was investigated in this study to assess its efficiency of treating the waste stream from dye works. Chitosan is produced by the deacetylation of chitin which is a natural chelating polymer extracted from the shells of arthropods such as lobsters, shrimps and crabs. The possibility of using chitosan as an adsorbent has been studied in this investigation, since it has the potential advantage of dyestuff recovery under different operating conditions. Box-Behnken methods and analysis of variance have been applied to the experimental determination of adsorption studies. Response surface method with three levels of temperature (30° C, 45°C, 60°C), pH (6.7, 8.1,9.5) and particle size (0.177 mm, 0.914 rnm, 1.651 mm) was used in the identification of significant effects and interactions in the equilibrium studies. This methodology requires no assumption and identifies the principal experimental variables, and their interactions, which have the greatest effect on adsorption. The experimental values are in good agreement with predicted values, the correlation coefficient was found to be 0.9977.