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Background and purpose: According to thetheory ofsustainable development, protect the environmentforcurrent and futuregenerationsisinevitable. Chromium (VI) is one of the pollutant of waterthatcauseharm totheaqueous environmentandrisksfor human health, animalsand plants. The purpose of this study was tosynthesis of Fe3O4 nanoparticlesand evaluateofCr (VI) adsorptionon Nanoparticle ssynthesizedasanadsorbent. Materials and methods: Inthisexperimental- laboratorystudy, nanoparticleswere synthesized bychemicalco-precipitation method and as an adsorbent was studiedforadsorptionof Cr (VI).The resulted nanomaterials were characterized by SEM, XRD and FT-IR. Effects ofpH, contacttime, adsorbentdoses andinitial Cr (VI) concentration werestudied. The resulting data were described by the Langmuir and Freundlich isotherm models and for Data analysis was used from Excel software. Results: The results showedthat thecharacterization ofnanoparticleswereas expectedandthe best of removal performance in pH= 2, at contact time equal10 min, adsorbentdose of 1g/L and initial Cr (VI) concentration of50 mg/L.The Pattern of Cr (VI) adsorption was fitted with the Freundlich model and Adsorption processes followed the pseudo second-order kinetics. Conclusion: chemical co-precipitation Synthesis methodbased onlow power consumptionandShort time isaappropriate methodandFe3O4nanoparticlessynthesizedby this methodcan be used as asuitable optionfor theadsorptionof Cr (VI).

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Background and purpose: Dyes and cyanide are the most important sources of environmental pollution, found in industrial wastewater, which are harmful for human health and environment. The purpose of this research was to investigate the Kinetic and efficiency of titanium dioxide photacatalytic process in removal of Reactive Black 5 (RB5) dye and cyanide from aquatic solution in a batch system.
Materials and methods: This research was an applied-fundamental study. Â reactor was designed and optimum dosage of TiÔ2 was determined, 1g/L keeping other parameters constant. The effect of pH, contact time and initial Reactive Black 5 )RB5) dye and cyanide concentration was studied at a constant concentration of TiÔ2 (1 g/L).
Results: The result showed that removal efficiency of Reactive Black 5 )RB5) dye and cyanide decreased with increasing pH and initial Reactive Black 5 )RB5) dye and cyanide concentration. There was also an increase in specific removal efficiency by increasing the contact time and the TiÔ2 dosage. Ïn addition, kinetic parameters were obtained by application of Langmuir and Hinshelwood equation.
Çonclusion: The results showed that removal of Reactive Black 5 )RB5) dye and cyanide can be efficiently performed by ÜV/TiÔ2

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Background and purpose: In oil and petrochemical industries, organic aromatic compounds such as furfural are produced on a large scale. They are degradable or act as a deterrent for biological systems. In order to generate sulfate radical (SO4), persulfate (S2O8-2, PS) is often activated by heat, UV irradiation and intermediate metals like iron ions. The aim of this study was to investigate the efficiency of activated S2O8-2 by electrically produced iron using the iron electrode (modern process of electro/ persulfate) for furfural removal. Material and methods: In this study, a lab-scale batch reactor equipped to 4 electrodes and direct power source was used to remove furfural. The effects of key parameters such as pH, voltage, initial concentration of S2O8-2 and furfural on the process were studied. Furthermore, we investigated the changes in pH during the process and the effect of the optimized situation Results: The findings showed that initial pH, S2O8-2 initial concentration and voltage played an important role in furfural removal. Under acidic situations, an increase in the efficiency was seen, and by raising pH the amount of furfural removal decreased. We observed that 98% of furfural was removed in 60 min (pH=3, voltage=10 V, S2O8-2 concentration=8.4 mM). When the concentration of furfural was raised, the efficiency declined. At pH=5, 7, 9 and 11 after 60 min, the efficiencies were 66, 53, 48 and 12, respectively. By increasing voltage to 10 V, the highest rate of efficiency was seen. By applying S2O8-2 separately, after 60 min the efficiency was 39% while at these conditions, the efficiency of the electrochemical process was only 28%. By contrast, electro/persulfate could remove 98% of furfural. Conclusion: The use of S2O8-2 ion in electrochemical reactors equipped to iron electrode can increase the efficiency of the process. Thus, the application of this novel process could be of great benefit for industrial wastewater plants operators.

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Background and purpose: Cadmium (Cd) is a toxic heavy metal that pollutes the environment via industrial, domestic and agricultural effluents. Its accumulation in aquatic ecosystem could have adverse effects on human health so, its removal from aquatic environment is of great importance. The aim of this study was to evaluate the performance of activated carbon coated iron nanoparticles for the removal of cadmium from aqueous solution. Moreover, kinetic and isotherm models were used to fit experimental data. Materials and methods: This fundamental and applied study was performed in laboratory. Adsorbent characterization was determined using X-ray dilatometer (XRD), scanning electron microscope (SEM), and FTIR. Factors affecting the adsorption process such as concentrations of cadmium, pH, time and adsorbent dose in removal of cadmium from aqueous solution were selected and evaluated. The experimental data were evaluated by various isotherm and kinetic models. Data analysis was performed using SPSS V.16. Results: Results of XRD and SEM showed that nanoparticles diameter were 20 nm that was well coated on to activated carbon. With increase in pH, time, concentration, and decreasing of Cd concentration, the rate of cadmium adsorption increased. The highest adsorption rate (approximately 90%) was obtained at pH 9.The results of cadmium adsorption were found to fit well with Freundlich isotherm model (R2> 0.94). Adsorption followed second-order kinetics. FTIR analysis revealed that O-H, C-O-H and amine groups played an important role in sorption of cadmium. Conclusion: According to the results, coated nanoparticles could be used to increase the adsorption efficiency of cadmium and as an effective method in removing of cadmium.

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Abstract Background and purpose: Conventional treatment processes do not have good efficiency in degradation and removal of antibiotics from aqueous environments, therefore, using advanced oxidation processes seems to be necessary. The aim of this study was to evaluate the performance of catalytic ozonation for degradation of cefazolin from aqueous environments and the effect of various parameters on the performance of this process. Materials and methods: In this experimental study after applying the process, the effect of different parameters were measured including pH (2-10), initial concentration of cefazolin (5-45 mg/L), catalyst dose (0.25-1 gr/L), ozone concentrations (1-5 mg/L.min), TBA concentration (0. 2mg/L) as a radical scavenger, the synergistic effect of the parameters, and reducing COD and TOC. Cefazolin concentrations and COD levels were measured by a spectrophotometer after the process and TOC was measured by TOC analyzer. Then the SEM images, BET analysis of nanoparticles, and XRD were prepared. Results: The optimum condition for the highest efficacy of the process was found to be pH 8, catalyst dose 0.5 gr/L, O3 concentration 5 mg/L.min and cefazolin concentration 5 mg/L. At this optimal condition the efficiency of process was 92.01%. In presence of TBA, the efficiency of process reduced. The efficiency of process in COD and TOC removal was 55% and 42%, respectively. Conclusion: The results showed that the process conducted in this study was useful in degradation and mineralization of cefazolin, and can be used in treatment of wastewater containing pollutants. One of the main features of this process is that it does not produce sludge and by-products. Removal of COD and TOC needs more reaction time.