The Removal of Crystal Violet (CV) Dyestuff by Wheat Bran: Kinetic Studies

Treatment of waste water containing dye from widespread use of dyestuff is an important environmental issue. For this reason, color removal processes from waste water of the textile industry containing dyestuffs gaining importance in terms of ecological. Nowadays, alternative methods are needed in order to efficiently and economically remove the dyestuffs in large volume wastewater. In the study, the adsorption of Crystal Violet (CV) which is common in textile waste waters on the wheat bran was investigated. The different initial dye concentrations, pH values, adsorbent concentrations and temperature parameters were tested in order to determine the effects of adsorption on the CV dyestuff and optimum conditions were provided. The highest removal was obtained at the natural pH (6.24). As the amount of adsorbent increased up to certain value, the removal of dyestuff increased. Besides, it was observed that the adsorption reached a balance at 120 minutes and the removal efficiency decreased as the dyestuff concentration increased. However, increasing the temperature from 25°C to 45°C increased the removal of the dyestuff. The suitability of experimental data with Langmuir and Freundlich isotherms and pseudo-first and pseudo-second order kinetic models has been investigated. The parameters of these models and the thermodynamic parameters of the adsorption process were calculated. As part of characterization studies, the functional groups in the biosorption mechanism were examined and structural changes after biosorption were observed by Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM) analyzes were performed for the wheat bran before and after the adsorption studies.