Environment and Natural Resources Journal (Jul 2024)
Optimization of Diclofenac Treatment in Synthetic Wastewater using Catalytic Ozonation with Calcium Peroxide as Catalyst
Abstract
This research studied the performance of ozonation process combined with calcium peroxide (CaO2) as a catalyst for the removal of diclofenac (DCF) from synthetic wastewater. The experiments were conducted using venturi-type ozonation with an ozone production rate of 96.30 mg/h. Response surface methodology (RSM) with a Box-Behnken experimental design (BBD) was used to investigate the DCF removal efficiency by optimizing the catalytic ozonation process and analyzing the influence of key parameters: solution pH (5.0-9.0), initial DCF concentration (10-25 mg/L), CaO2 dosage (1-3 g/L), and reaction time (30-90 min), on the DCF removal efficiencies. Analysis of variance (ANOVA) indicated that the experimental model derived from the RSM-BBD was best suited to a quadratic regression model, with a coefficient of determination (R2) of 0.84. The model demonstrated that the optimal conditions for achieving the highest DCF removal efficiency of up to 100% were an initial DCF concentration of 10 mg/L, solution pH of 7, CaO2 dosage of 2 g/L, and reaction time of 90 min. Using these conditions, the actual DCF removal efficiency from a confirmation test was 97.6%. The accuracy of the model was verified; the root mean square error (RMSE) was 5.90 and the mean absolute percentage error (MAPE) was 6.10%, indicating that the regression model could be used to predict the DCF removal efficiency under various conditions. The results showed that catalytic ozonation using CaO2 as a catalyst could effectively remove DCF in synthetic wastewater.
Keywords