Adsorption of crystal violet from quaternary dye mixture onto sawdust: statistical analysis and optimization studies

The selective adsorption of crystal violet from dye mixture of methylene blue, malachite green, and Rhodamine B using sulphuric acid-treated sawdust of Parkia biglobosa was investigated through crossed composite Design of Experiments. The competitive effects of mixture components and process parameters on the adsorption process were studied and optimized using response surface methodology. The optimum contact time, pH, adsorbent dose and temperature were found to be 275.10 min, 9.94, 0.99g and 60 oC respectively for the maximum decolorization of 68.39 mg/L CV (97.2%). A linear model was obtained for the dye decolourization through this design. The experimental values were in good agreement with predicted values and the model developed was highly significant with the correlation coefficient of 0.985. Experimental results were analyzed by Analysis of variance (ANOVA) statistical concept