Catalytic effect of Fe@Fe2O3 nanowires and Fenton process on carbamazepine removal from aqueous solutions using response surface methodology

• Main Authors: M.M. Amin, S. Yousefinejad, M. Dehghani, S. Rahimi
• Format: Article
• Language: English
• Published: GJESM Publisher 2019-04-01
• Series: Global Journal of Environmental Science and Management
• Subjects: Carbamazepine removal; Fenton process; Nano catalyst, Response surface methodology (RSM)
• Online Access: https://www.gjesm.net/article_34364_79206b2c446ccc118a15f1a772ba8be5.pdf
• ISSN: 2383-3572; 2383-3866

Carbamazepine is one of the hydrophilic compounds identified in aquatic environments. Due to toxicity and bio-stability of this psychotropic pharmaceutical in the environment and humans, its removal efficiency and mineralization are important. In this study, synthesized Fe@Fe₂O₃ nanowires were applied to improve Fenton oxidation process using FeCl₃.6H₂O and NaBH₄. The effects of different parameters such as initial pH, H₂O₂, FeSO₄.7H₂O, carbamazepine concentrations, oxidation time, and nanowires dose were evaluated using response surface methodology. After scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffract meter analysis, Fe@Fe₂O₃ morphology was synthesized in the form of nanowires with diameters of about 40-80 nm. The optimum oxidation conditions for carbamazepine were established at pH= 4.3, reaction time of 45.9 min, nanowire dose of 179.4 mg/L as well as H₂O₂, FeSO₄.7H₂O and carbamazepine concentrations of 22, 52.2 and 7.7 mg/L, respectively. The oxidation efficiency (99.5%) achieved under the optimum condition, which was determined by the model, was consistent with the efficiency predicted by the model. The multi-parameter models showed good calibration and prediction abilities with R²₌0.922, R²_adj= 0.907, R²_pred= 0.868. According to the results, the carbamazepine degradation rate increased with the increase of Fe²⁺ due to the synergistic effect between Fe@Fe₂O₃ and Fe²⁺ on the catalytic decomposition of H₂O₂and generation of OH•. It was concluded that the Fenton process based on the Fe@Fe₂O₃ nanowires can increase the carbamazepine oxidation rate in aqueous solutions. This method can also be used as an effective and pre-treatment process in the conventional treatment plants.