OXIDATIVE DEGRADATION OF CRYSTAL VIOLET DYE

ABSTRACT

This study focused on the oxidative degradation of crystal violet dye using tigernut as bioadsorbent. It explore to investigate the potential use of tigernut (unmodified and modified) as adsorbent for the removal of crystal violet dye from aqueous solution. The batch experimental setup was used to determine the optimum conditions for the adsorption process by varying the effect of various operating parameters such as adsorbent dosages, contact time, pH, temperature and initial dye concentrations. The batch adsorption shows the optimum conditions for both unmodified and modified to be adsorbent dosage of 2.375g (98.05 and 99.13 %), contact time of 90 min (99.42 and 97.47 %), temperature of 40oC (96.79 and 97.46 %) and initial concentration of 25 mg/l (99.32 and 99.09 %). The rate of adsorption process was analyzed using different kinetics models such as pseudo-first order, pseudo-second order, intra-particle diffusion and Elovich model. Results showed that the pseudo-second order kinetics best described the adsorption of crystal violet unto Tigernut, this indicate that the adsorption is governed by chemi-sorption. Furthermore, the thermodynamics parameters (∆𝐺 𝑜 , ∆𝐻 o , ∆S°) indicates that the current process was spontaneous as well as endothermic in nature. The results in this study indicated that Tigernut thought it is a low cost, effective and environmental friendly adsorbent can be considered suitable for the removal of crystal violet dye from aqueous solution.