Adsorption of crystal violet onto hibiscus Rosa Sinensis

Abstract

The removal of the textile dye, crystal violet (CV), from aqueous solutions was studied by adsorptionon Hibiscus rosa sinensis. Batch adsorption studies were conducted by varying the  initial concentration of the adsorbate, adsorbent dosage, contact time, and pH. The effect of pH on adsorption of crystal violet ontoHibiscus rosa sinensis was studied at pH 4. The percentage removal of dye was measured as a function of both the concentration of the dye (10 - 30 ppm) and the temperature (303 – 323 K). The experimental data were fitted into the Freundlich and Langmuir adsorption isotherm equations. The values of their corresponding constants were determined. Thermodynamic parameters like free energy, enthalpy and entropy of the systems were calculated using Freundlich constant. The present study shows that nearly80% removal of crystal violet was observed and hence Hibiscus rosa sinensiswas found to be an efficient adsorbent for the removal of the basic dye crystal violet from aqueous solutions.