Simin Shokrolahi; Mehrdad Farhadian; Nila Davari
Abstract
ZnO/Fe2O3/Zeolite nanophotocatalyst was synthesized by sol-gel method, and its performance in degradation of ENR, as one of the most commonly used veterinary antibiotics, is evaluated. The synthesized nanophotocatalyst is characterized by XRD, XRF, FT-IR, FE-SEM, EDX, and BET analyses. According to XRD, ...
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ZnO/Fe2O3/Zeolite nanophotocatalyst was synthesized by sol-gel method, and its performance in degradation of ENR, as one of the most commonly used veterinary antibiotics, is evaluated. The synthesized nanophotocatalyst is characterized by XRD, XRF, FT-IR, FE-SEM, EDX, and BET analyses. According to XRD, FT-IR, and EDX, presence of ZnO and Fe2O3 on the zeolite surface is confirmed. Based on XRF results, the optimal molar value of Fe3+/ZnO in the synthesized nanophotocatalyst is obtained as 0.06. The FE-SEM results confirm the deposition of ZnO/Fe2O3 on the zeolite surface and indicate the approximate size of the photocatalyst particles as 48 nm. According to BET results, the specific surface area and pore volume for the synthesized nanophotocatalyst are obtained as 280.16 m2/g and 0.35 cm3/g, respectively. The simultaneous effects of operational factors, including the concentration of pollutant (150-450 mg/l), initial pH of the solution (5-9), and H2O2 concentration (50-200 mg/L) are examined on the ENR degradation efficiency via RSM. The results demonstrate that ENR concentration, pH, and H2O2 concentration have significant impacts on the ENR degradation efficiency in turn. According to the experimental results under optimal conditions (pH, contaminant concentration, and H2O2 concentration: 9, 500 mg/l, and 90 mg/l, respectively), the ENR degradation efficiency is 97.4%. This study suggests that the synthesized nanophotocatalyst has an acceptable efficiency to degrade a non-biodegradable contaminant.
Danial Nayeri; Seyyed Alireza Mousavi; Azadeh Mehrabi
Abstract
In this study, oxytetracycline removal from aqueous solution by activated carbon prepared using corn stalks has been investigated. The adsorbent was characterized using Fourier transform infrared spectrophotometer (FTIR) and scanning electron microscope (SEM). The effects of main variables; adsorbent ...
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In this study, oxytetracycline removal from aqueous solution by activated carbon prepared using corn stalks has been investigated. The adsorbent was characterized using Fourier transform infrared spectrophotometer (FTIR) and scanning electron microscope (SEM). The effects of main variables; adsorbent dose, contact time, pH, and initial oxytetracycline concentration on the efficiency of adsorption efficiency were investigated. Results confirmed the effects of main variables and the maximum removal of antibiotic (99.9 %) achieved at initial concentration of 10 mg/L, pH of 9, and contact time of 60 min, when adsorbent dose was 1.5 g. The results of isotherm and kinetic studies showed that the oxytetracycline adsorption onto activated carbon prepared from corn stalks follows Freundlich isotherm (R2 = 0.98) and pseudo-second order kinetic model (R2 = 0.99). The maximum adsorption capacity of oxytetracycline was 522.6 mg/g. In brief, the activated carbon that has been prepared from corn stalks as low cost, non-toxic and environment friendly adsorbent shows a good ability for removal of oxytetracycline form water and wastewater.
