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.
Somayyeh Akberi; Abdolmotalleb Seyyed Mohammadi; Javad Fardmal; Qorban Asgari
Volume 22, Issue 5 , November and December 2015, , Pages 870-878
Abstract
Background: Phenol is one of the toxic saline wastewater pollutants that is considered as priority pollutants since it is necessary treatment and reached the phenol concentration to the level of effluent discharge standard before discharge into the environment. In this study the performance of electro-Fenton ...
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Background: Phenol is one of the toxic saline wastewater pollutants that is considered as priority pollutants since it is necessary treatment and reached the phenol concentration to the level of effluent discharge standard before discharge into the environment. In this study the performance of electro-Fenton process in phenolic saline waste water treatment and the removal degree of COD were investigated. Materials and Methods: In this experimental study a reactor (1 litre) which was equipped to four iron electrodes and a DC power supply used to remove phenol and COD. The effect of operating parameters such as phenol initial concentration, H2O2 dosage, electrolyte concentration, pH, current density, connection time and type of electrode connection were investigated. Results: The results showed that this process using iron electrodes with parallel monopole connections is able to leave out the phenol from saline waste water by 96% and the removal COD equals 59% in operating conditions: pH= 3, initial phenol concentration=500mg/l, H2O2 concentration = 150 mg/L, Hydrogen peroxide at a current density = 15 mA/cm2at 10 minutes. Conclusion: The results showed that electrochemical processes can be considered as a better suitable substitute rather than other methods due to saline content and high electrical conductivity in saline wastewater.