Catalytic Potential of Nano-Magnesium Oxide on Degradation of Humic Acids From Aquatic Solutions

Catalytic ozonation is a new and promising process used to remove the contaminants from drinking water and wastewater. This study aimed to evaluate the catalytic potential of nano-magnesium oxide (nano-MgO) for the removal of humic acids (HA) from water. Mg (NO3)2 solution was used to prepare MgO powder by the calcination method. In a semi-batch reactor, the catalytic ozonation was carried out. The effects of the various operating parameters, including pH, reaction time, T-butyl alcohol (TBA) and phosphate on HA degradation were evaluated. Experimental results indicated that degradation of HA was increased as the pH solution and reaction time were increased. Maximum HA degradation was obtained at pH = 10 and the reaction time of 10 minutes in the catalytic process. The calculated catalytic potential of nano-MgO on ozonation of HA was 60%. Moreover, catalytic ozonation process was not affected by TBA and the main reaction on HA degradation HA have effect take place on MgO surface. According to the results of this study, the developed MgO catalyst is the active and proficient catalyst in HA degradation using the catalytic ozonation process

Investigation of Heterognous Fenton with nZVI Perfomance in Dimethylphthalate Removal from Aqueous Solutions

Background and purpose: Stability of new synthetic compounds such as Dimethyl phthalate increased their concentration in the environment and food chain and caused health risks. Therefore, achieve effective and efficient methods to removal of pollutants are one of the environmental researchers concern. This study investigates efficiency of heterognous Fenton process using  nZVI in dimethylphthalate removal from aqueous solutions. Materials and Methods: This experimental study was conducted in batch reactor in laboratory scale and the efficiency of heterognous Fenton process was analyzed in a batch system with the effect of changes in operating parameters such as reaction time (15 to 120 min), pH (2 to10), H2O2 concentration (0.01 to 1 mmol/L), nZVI dose (0.01 to 0.5 mg/L) and initial concentration of Dimethyl phthalate (2 – 50 mg /L). Then the effect of each heterogeneous Fenton regent in dimethyl phthalateremoval was determined. Results: The results showed that the maximum efficiency of heterognous Fenton process in removal of Dimethyl phthalate is at pH=4. Also in optimal conditions, the parameters affecting reaction was determined  as H2O2 concentration 0.1 mmol/L, nZVI dose 0.05 gr/L, Dimethyl phthalate concentration 2 mg/L and 120 minute, amount of Dimethyl phthalate removal was 92.8%. Conclusion: According to the results, heterognous Fenton process using  nZVI has an optimal efficiency in removal of Dimethyl phthalate from aquatic solutions and can be considered as an acceptable and low Cost method for the removal of similar compounds

Monitoring of pH, Oxidation-Reduction Potential and Dissolved Oxygen to Improve the Performance of Dimethyl Phthalate Removal From Aqueous Solutions

Since the process of heterogeneous Fenton is more complex and dynamic than the common Fenton process, control and online monitoring is entirely vital for optimum operation of this system. This study was aimed to investigate the effects of pH, oxidation-reduction potential (ORP) and dissolved oxygen (DO) variations on dimethyl phthalate (DMP) removal from aqueous solutions using the heterogeneous Fenton process with nano zero-valent iron (nZVI). Parameters affecting the process like contact time (5 - 120 minutes), pH (2 - 10), H2O2 concentration (0.01 - 1 mmol/L) nZVI content (0.01 - 0.5 g/L) and initial DMP concentration (2 - 50 mg/L) were also studied. It was found that, at optimum amounts (pH = 4, H2O2 concentration = 0.1 mmol/L, nZVI = 0.05 g/L, initial DMP concentration = 2 mg/L, and contact time = 60 minutes), approximately 98% of the pollutant was removed. This process could treat DMP well from aqueous environments and can be introduced as a cheap and effective method

Application of Heterognous Fenton Process Using Zero-Valent Iron Nanoparticles in Dimethylphthalate Removal from Aqueous Solutions

Background and purpose: Stability and sustainable [s1] of emerging synthetic compounds such as Dimethyl phthalate lead to increasing their concentrations in environment and food chain and health risks. Therefore, researchers are concern to achieve effective and efficient methods for removal these pollutions. This aim of this study was to evaluation of the efficiency of heterognous Fenton using Zero-valent iron nanoparticles in dimethylphthalate removal from aqueous solutions. Materials and Methods: This experimental study was conducted in laboratory scale in batch reactor. The effects of operational parameters such as reaction time (15 to 120 min), pH (2 to10), H2O2 concentrations (0.01 to 1 mmol/L), nZVI dose (0.01 to 0.5 mg/L) and initial concentrations of Dimethyl phthalate (2 – 50 mg /L) determined by one at a time method. Then effect of each heterogeneous Fenton regent was determined in dimethyl phthalate removal. Results: The results showed that maximum efficiency of heterognous Fenton process in dimethylphthalate removal occur at pH=4. Also at H2O2 concentration 0.1 mmol/L, nZVI dose 0.05 g/L, Dimethyl phthalate concentration 2 mg/L and reaction time 120 minute, amount of Dimethyl phthalate removal was 92.8%. Conclusion: According to the results, nZVI- heterognous Fenton process has appropriate efficiency in Dimethyl phthalate removal from aquatic solutions and can be assumed as an effective and applied method for removal similar compounds from industrial wastewater