Pezhman Gheitasian; Seyed Mohammad Tabatabaee jabali; Ahmad Jonidi Jafari; Mohsen Farhadi; Javad Golshani asl; Behzad Valizadeh; Maryam Meserghani
Abstract
Background and Purpose: Tetracycline represents the most prevalent antibiotic group in production and utilization and is extensively employed for the prophylaxis and treatment of infectious diseases in both human and veterinary medicine. The primary objective of this investigation was to assess the efficacy ...
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Background and Purpose: Tetracycline represents the most prevalent antibiotic group in production and utilization and is extensively employed for the prophylaxis and treatment of infectious diseases in both human and veterinary medicine. The primary objective of this investigation was to assess the efficacy of electro-activated persulfate (EC/PS/HR) for eliminating tetracycline from aqueous solutions.Materials and Methods: This study was conducted in a batch mode utilizing an electro-activated persulfate (EC/PS/HR) system. All experiments were carried out under constant temperature conditions. Response surface methodology (RSM) in conjunction with a central composite design (CCD) was employed to optimize the variables associated with the electro-activated persulfate and hydrogen peroxide process, including pH, current density, and the persulfate/hydrogen peroxide molar ratio, with the aim of tetracycline removal. Data analysis in this study was performed using Data Designer 8.0.6 software.Results: The results of this study revealed the use of a quadratic model to predict the impact of independent variables on the efficiency of tetracycline removal in the process. The exceedingly low (p <0.0001) and the high correlation coefficient (R2) of the obtained model signify a robust correlation between experimental and predicted data. The optimal conditions for achieving maximum efficiency in the degradation of tetracycline through electro-activated persulfate were determined to be a pH of 5.6, a persulfate/hydrogen peroxide molar ratio of 1.1, and a current density of 31 mA. Under these conditions, tetracycline degradation reached approximately 95.2%.Conclusion: Based on the findings of this investigation, it can be deduced that the advanced oxidation process relying on electro-activated persulfate (EC/PS/HR) is capable of eliminating contaminants in aqueous environments, influenced by various factors such as hydrogen peroxide dosage, catalyst concentration (persulfate), and pH. The study highlights the capability of the electro-activated persulfate (EC/PS/HR) hybrid process to decompose recalcitrant pollutants like tetracycline from aqueous environments. Overall, the electro-activated persulfate process demonstrates promise for the degradation of tetracycline in aqueous solutions.
Anis Jahantigh; Hossien Kamani; Elham Norabadi; Edris Bazrafshan; Fateme Sancholi; Ali Meshkinian
Abstract
Abstract Backgroundandpurpose:Chlorophenols are one of the toxic compounds in the industries that are resistant to biodegradation and they last a long time in environment. Therefore, it is necessary to eliminate them and prevent pollution of the receiving waters. The aim of this study was evaluation ...
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Abstract Backgroundandpurpose:Chlorophenols are one of the toxic compounds in the industries that are resistant to biodegradation and they last a long time in environment. Therefore, it is necessary to eliminate them and prevent pollution of the receiving waters. The aim of this study was evaluation of ZnO nano-particles for removal of 2,4,6-trichlorophenol from aqueous solution based on the response surface methodology (RSM) model. Materials and methods: Effect of independent variables including pH, catalyst dose, contact time and the initial concentration of 2,4,6-trichlorophenol on response variable (removal of 2,4,6-trichlorophenolfrom) were evaluated based on the response surface methodology (box-behnken method). In this study, all experiments were carried out in a batch reactor containing ZnO nano-particles under 15 Watt UV lamp Results:The results showed that the best conditions for the removal of 2,4,6-trichlorophenolwere achieved at pH= 3,nano-particle concentration 0.4g/l, reaction time and74.72 min and initial concentration of 2,4,6-trichlorophenol50 mg/l contact time (95.85% removal efficiency). Results: The results showed that the best conditions for removal of 2,4,6-trichlorophenol were achieved at pH=3, nano-particle concentration 0.4g/l, reaction time 74.72 min, initial concentration of 2,4,6-trichlorophenol 50 mg/l (95.85% removal efficiency). Conclusion: The results showed that photocatalytic process was accelerated in the presence of ZnO nano-particle and enhanced removal of 2,4,6-trichlorophenol.
Mitra Gholami; Mojtaba Davoudi; Simin Naseri; Amir Hossein Mahvi; Mehdi Farzadkia; Ali Esrafili; Hossein Alidadi
Abstract
Backgrounds & Objectives: Elimination of phenolic compounds which is considered as resistant pollutants to biological degradation has a great importance. This study aims to investigate the electrochemical oxidation process efficiency in removal of phenol compounds using a continuous and divided rector. ...
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Backgrounds & Objectives: Elimination of phenolic compounds which is considered as resistant pollutants to biological degradation has a great importance. This study aims to investigate the electrochemical oxidation process efficiency in removal of phenol compounds using a continuous and divided rector. Materials & Methods: The catalytic anodes of Ti/SnO2-Sb and cathodes of iron were employed in a reactor divided into anolyte and catholyte chambers by a cellulosic separator. The influence of initial phenol concentration (14.12‒40.88 mg L‒1), retention time (32.23‒82.77 min), and current intensity (0.18‒0.42 A) on TPh removal efficiency, TPh residual concentration, and energy consumption was investigated using response surface methodology. Results: The results showed that TPh removal efficiency strongly depends on retention time, followed by current intensity and initial phenol concentration. The importance order of factors affecting on TPh residual concentration were distinguished as initial TPh concentration > retention time > current intensity. The energy consumption in terms of kWh m‒3 is mostly affected by retention time and then current intensity, and irrespective of initial phenol concentration. Under the optimal conditions, removal efficiency of 93.21%, residual concentration of 1 mg L‒1, and energy consumption of 34.40 kWh m‒3 is achieved. Conclusion: Based on the obtained results, the electro-oxidation is a very efficient process for diminution of wastewater phenolic content, and is able to set the allowable limits to discharge to the environment.