Health and environment
Mousa Aminivafa; Ahmad Allahabadi; Golamreza Moussavi; Hosein Fahimi
Volume 28, Issue 6 , January and February 2022, , Pages 838-849
Abstract
Background and Objectives: Antibiotics, comprising a significant amount of pharmaceutical compounds, are used as human and veterinary treatments . these antibiotics come to appear as contaminantoin soil, surface water, groundwater, and even drinkingwater.Advanced oxidation processes such as catalytic ...
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Background and Objectives: Antibiotics, comprising a significant amount of pharmaceutical compounds, are used as human and veterinary treatments . these antibiotics come to appear as contaminantoin soil, surface water, groundwater, and even drinkingwater.Advanced oxidation processes such as catalytic ozonation are effective to remove the antibiotics form water and wastewaterThe aim of this study was to investigate the efficiency of Catalytic Ozonation Process for tetracycline antibiotics removal from contaminated watersMaterial and method:In this design, an ozonation pilot with a volume of 200 cc was used. In each experiment, the tetracycline solution was poured into the desired concentration, the pH of the sample was adjusted with sulfuric acid and NaOH. At different times of 5 to 30 minutes and different pHs of 2 to 10 ozonation was performed at the dose of 0.8 mg/min. Then, under these conditions, ozonation was performed in the presence of activated carbon catalyst and a sample was discharged from the pilot and analyzed (HPLC) to determine the remaining tetracycline.Results:The results showed that under optimum conditions of pH= 8 and ozone dose of 0.8 mg / min and contact time of 30 minutes ozonation only eliminated 59% of tetracycline and in the same conditions catalytic ozonation with 0.01 g/L carbon. The Calligonum comosum tree was able to remove 100% tetracycline in 30 minutes.Conclusion: The results of this study showed that carbon catalyzed ozonation from wood Calligonum comosum waste can be used as an advanced treatment method.
Gholamreza Moussavi; Ahamd Allahabadi; Milad Ganbary; Morteza Dab; Fahimeh Mircholi
Volume 23, Issue 4 , September and October 2016, , Pages 652-661
Abstract
Background Malathion is a pesticide with the highest consumption in phosphoric pesticides. This pesticide has acute and chronic effects. Therefore, for the protection of the water and human health against the harmful effects of these compounds, they must be removed by appropriate treatment of wastewater ...
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Background Malathion is a pesticide with the highest consumption in phosphoric pesticides. This pesticide has acute and chronic effects. Therefore, for the protection of the water and human health against the harmful effects of these compounds, they must be removed by appropriate treatment of wastewater and water resources. Among the treatment methods, the ozonation process has drawn more attention; one of the best options of ozonation process is the catalytic ozonation process (COP)with activated carbon.Materials & Methods In this study, at first the synthetic wastewater was prepared at the mentioned concentration with pure malathion. Then, removal malathion experiments in a cylindrical pilot with a total volume of 200 mL were performed by single ozonation and catalytic ozonation process with use of NH4Cl-induced activated carbon (NAC) obtained from of agricultural waste. Study variables included pH, contact time, the concentration of ozone, and the concentration of catalyst. In all conditions, the sole catalytic ozonation adsorption and catalystic synergistic effects were evaluated.Results The results showed that the removal efficiency of ozone in alkaline pH is higher. Also, in 200 mL samples containing 50 mg/L malathion and 0.1 g/L concentration of catalyst in carbon NAC, in the COP test for 50 minutes, the malathion removal performance was 62.9% in ozonation; 100% in catalytic ozonation, 22% in adsorbtion only, and 15.1% in the synergism effect. It showed the high removal efficiency of COP/NAC.
Ashkan Abdoli; Reza Shokohi; Abdolmotalleb SeydMohammadi; Qorban Asgari
Volume 23, Issue 1 , May and June 2016, , Pages 84-94
Abstract
Background & Objectives: Antibiotics can cause negative impacts on animals and bacterial resistance by entering to the environment. Catalytic ozonation process is a method for increasing the efficiency of the simple ozonation. This study evaluated the efficiency of catalytic ozonation process with ...
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Background & Objectives: Antibiotics can cause negative impacts on animals and bacterial resistance by entering to the environment. Catalytic ozonation process is a method for increasing the efficiency of the simple ozonation. This study evaluated the efficiency of catalytic ozonation process with activated carbon modified with MgO to remove metronidazole from aqueous solutions in a fluidized bed reactor. Materials & Methods: Catalytic ozonation experiments were performed in a fluidized bed reactor. Impact of pH, reaction time, catalyst dosage, initial concentration, radical scavengers and hydroxyl radicals was found. The degradation kinetic of metronidazole was determined as well as FTIR spectra of the catalysts. The concentration change of metronidazole was determined by HPLC. Results: The results showed that the catalyst prepared increases metronidazole decomposition rate as high as 7.32 times, compared to conventional ozonation. The optimum pH of 10, the optimal dose of 1.5 g/L of catalyst and the optimum time of 30 min were determined. The results of radical scavengers’ effect showed the main reactions of metronidazole decomposition are on the catalyst surface. Conclusions: The results showed that, due to the high performance activated carbon coated with MgO in catalytic ozonation process, increased removal of metronidazole, compared with simple ozonation, and easy access to raw materials, the use of these catalysts in ozonation process are recommended to increase efficiency and accelerate the metronidazole decomposition reaction and similar compounds.