%0 Journal Article %T Removal of metronidazole antibiotic pharmaceutical from aqueous solution using TiO2/Fe2O3/GO photocatalyst: Experimental study on the effects of mineral salts %J Advances in Environmental Technology %I Iranian Research Organization for Science and Technology %Z 2476-6674 %A Farhadian, Mehrdad %A Entezami, Negin %A Davari, Nila %D 2019 %\ 01/01/2019 %V 5 %N 1 %P 55-65 %! Removal of metronidazole antibiotic pharmaceutical from aqueous solution using TiO2/Fe2O3/GO photocatalyst: Experimental study on the effects of mineral salts %K Mineral salts %K Reaction rate constant %K Titanium dioxide %K Graphene Oxide %K Iron oxide (III) %R 10.22104/aet.2020.3952.1196 %X A TiO2/Fe2O3/GO photocatalyst is synthesized via the sol-gel method and characterized by X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), FT-IR, Brunauer-Emmett-Teller (BET), and Ultraviolet-Visible Diffuse Reflection Spectroscopy (UV-Vis DRS) analyses. Metronidazole (MET) concentration (10-20 mg/L), photocatalyst concentration (0.5-1.5 g/L), irradiation time (60-120 min), and initial pH (4-6) are investigated through response surface methodology (RSM), and the optimal process conditions are determined. The removal efficiency of MET with the TiO2/Fe2O3/GO photocatalyst is 97% under optimal conditions: a pollutant concentration of 10 mg/L, the irradiation time of 120 min, photocatalyst concentration of 1 g/L, and pH of 5. The influence of mineral salts concentrations (50-800 mg/L), including NaCl, Na2SO4, NaHCO3, KCl, MgSO4, and CaCl2, are examined at the initial pH of 5, photocatalyst concentration of 1 g/L, and pollutant concentration of 20 mg/L. According to the results, the reaction rate constant decreases with an increase in mineral salts concentrations up to 800 mg/L, especially with Na2SO4 (42.43% deactivation) and also with MgSO4 (38.08%) and NaHCO3 (37.73%), under the same operational conditions. The effects of mineral salts such as NaCl and KCl on the reaction rate constant for the contaminant removal efficiency have a downward trend until these salts reach a 200 mg/L concentration, and then they experience an upward trend. %U https://aet.irost.ir/article_899_017b6d23a2f8fa6bb41d3f22618494d0.pdf