The Removal of Sulfamonomethoxine (SMM) with Copper Oxide/Zirconium Dioxide (CuO/ZrO2) Nanocomposites by Photocatalytic Degradation in Pharmaceutical Industry Wastewaters and the Evaluation of Microtox (Aliivibrio fischeri) and Daphnia magna Acute Toxicity Assays

Abstract

In this study, Copper oxide/zirconium dioxide (CuO/ZrO2) nanocomposites (NCs) as a photocatalys was examined during photocatalytic degradation process (PDP) in the efficient removal of Sulfamonomethoxine (SMM) from pharmaceutical industry wastewater (PI ww) plant, İzmir, Turkey. Different pH values (3.0, 4.0, 7.0, 9.0, 10.0 and 12.0), increasing SMM concentrations (5, 10, 20 and 40 mg/l), increasing CuO/ZrO2 NCs concentrations (100, 200, 400, 800 and 1000 mg/l), different CuO/ZrO2 NCs mass ratios (1/2, 2/3, 3/4, 4/4, 4/3, 3/2, 2/1), increasing recycle times (1., 2., 3., 4., 5., 6. and 7.) was operated during PDP in the efficient removal of SMM in PI ww. The characteristics of the synthesized nanoparticles (NPs) were assessed using XRD, DRS, FESEM, EDX, FTIR, TEM and XPS analyses, respectively. The acute toxicity assays were operated with Microtox (Aliivibrio fischeri also called Vibrio fischeri) and Daphnia magna acute toxicity tests. The photocatalytic degradation mechanisms of CuO/ZrO2 NCs and the reaction kinetics of SMM were evaluated in PI ww during PDP. Cost analysis was evaluated for SMM removal with CuO/ZrO2 NCs by PDP in PI ww. ANOVA statistical analysis was used for all experimental samples. Maximum 99.6% SMM removal was obtained during PDP in PI ww, at 350 W UV-vis light irradiation power, at 147 mW/cm2 light intensity, after 120 min, at pH=12.0 and at 25oC, respectively. Maximum 99.2% SMM removal was found with PDP in PI ww, at 5 mg/l SMM, at 350 W UV-vis, at 147 mW/cm2, after 120 min, at pH=12.0 and at 25oC, respectively. Maximum 99.5% SMM removal was measured to 800 mg/l CuO/ZrO2 NCs with PDP in PI ww, at 5 mg/l SMM, at 350 W UV-vis, at 147 mW/cm2, after 120 min, at pH=12.0 and at 25oC, respectively. Maximum 99.4% SMM removal was measured at 4/3wt CuO/ZrO2 NCs mass ratios, at 5 mg/l SMM, at 800 mg/l CuO/ZrO2 NCs, at 350 W UV-vis, at 147 mW/cm2, after 120 min, at pH=12.0 and at 25oC, respectively. Maximum 99.5% SMM recovery was measured in PI ww during PDP, after 1. recycle time, at 5 mg/l SMM, at 800 mg/l CuO/ZrO2 NCs, at 4/3wt CuO/ZrO2 NCs mass rartio, at 350 W UV-vis, at 147 mW/cm2, after 120 min, at pH=12.0 and at 25oC, respectively. 97.31% maximum Microtox acute toxicity removal was found in SMM=20 mg/l after 180 min, and at 60oC. It was observed an inhibition effect of SMM=40 mg/l to Microtox after 180 min, and at 60oC. 93.27% maximum Daphnia magna acute toxicity removal was obtained in SMM=20 mg/l after 180 min, and at 60oC, respectively. It was obtained an inhibition effect of SMM=40 mg/l to Daphnia magna after 180 min and at 60oC. As a result, the CuO/ZrO2 NCs during PDP in PI ww was stable in harsh environments such as acidic, alkaline, saline and then was still effective process. Finally, the combination of a simple, easy operation preparation process, excellent performance and cost effective, makes this CuO/ZrO2 NCs a promising option during PDP in PI ww treatment.