Optimization of Reactive Blue 19 dye removal using ozone and ozone/UV employing response surface methodology

摘要

This work reports the degradation of Reactive Blue 19 (RB19) dye using ozone and ozone/UV. The effects of operationalparameters such as pH, ozone concentration and UV radiation were examined. A two factor with three levels factorialdesign was carried out and the interaction between variables was studied. Response surface methodology was appliedin order to optimize ozone concentration, pH and UV radiation in terms of the half life time required for discolorationand/or mineralization of the solution. Equations of color and TOC half-life time with respect to operational conditionswere determined. Contour plots and a desirability function were used to find the local points of optimization. Optimizedreaction conditions were established as pH 8.26, UV radiation of 40 W and ozone concentration of 50 g Nm~(−3). A specificexperiment was carried out under the optimal conditions where RB19 half life time was 1.59 min and TOC half life timewas 30.98 min, confirming the agreement between model and experimental results. The obtained results confirm ozonationas a promising alternative for treatment of wastewater with a high content of recalcitrant reactive dyes.