Iranian Journal of

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Backgrounds and Objectives: Industrial wastewater included the heavy metal is one of the important sources of environmental pollution. Hexavalent chromiumand divalent nickel are founded in plating wastewater which is harmful for human health and environment. Therefore, the purpose of this research is investigation of photocatalytic removal of hexavalent chromium and divalent nickel from aqueous solution using UV/TiO2 process in a batch system.
Materials andMethods: At first, reactor was designed. Then, optimumdosage of TiO2 was obtained equal to 1 g/L, with variation TiO2 dosage at constant pH and initial concentrations of hexavalent chromium and divalent nickel. The effect of pH, contact time and initial concentration of hexavalent chromium was studied at the constant amount of TiO2 (1gr/L).
Results: The result showed that photocatalytic removal efficiency increased with increasing reaction time and TiO2 dosage. In addition, it was found that removal efficiency of hexavalent chromium was decreased by increasing initial chromium concentration and pH. But, photocatalytic removal efficiency of nickel ion was increased and decreased by increasing of pH and initial nickel concentration, respectively.
Conclusion: The results showed that UV/TiO2 was an effective method in removal of hexavalent chromium and divalent nickel from aqueous solutions

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Backgrounds and Objectives: Treatment of colored wastewater is one of the important challenges of environmental engineers. Adsorption process is a key option for removal of organic matter from wastewater. The aim of present work was to investigate pumice stone as an adsorbent for removal of Acid Black 1 from aqueous solution.
Materials and Methods: Removal of Acid Black 1 by pumice stone was investigated. Acid Hyrdo Chloric(HCL) 1 N was used to increse adsorbent porosity. Various parameters such as pH, initial dye concentration and contact time were studied.
Results: Results showed that removal of Acid Black 1 was increased by increasing of contact time and initial dyeconcentration although it was decreased by increasing of pH. Experimental data was best fitted to Longmuir isotherm model (r2>0.98). Study of diffusion model revealed that intraparticle diffusion is rate-controlling step in removal of Acid Black 1 by pumice stone.
Conclusion : The results indicated that pumice stone was a dominant adsorbent for Acid Black 1 removal.

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Background and Objectives: Industrial wastewater included the dyes one of the important sources of environmental pollution, that founded in loom wastewater which are harmful for human health and environment. Therefore, the purpose of this research was investigated removal of RB5 dye from aquatic solution by using of adsorption onto synthesized magnetic sodium alginate beads.
Material and Methods: At first, synthesized magnetic sodium alginate beads. Then, acquired beads optimum dosage equal to 18 g/100CC, with constant other parameters. The effect of pH, contact time and initial RB5 dye concentration was studied at the constant of beads (18 g/100CC).
Results: Results showed that removal efficiency was decreased by increasing of initial RB5 dye concentration. Also the results showed the removal efficiency was increased by increasing of adsorbent dose and contact time. The results showed data were explained acceptably by Langmuir isotherms and pseudo-second-order kinetics models respectively.
Conclusion: The results showed that removal of RB5 dye from aqueous solution by using of magnetic sodium alginate beads can be done cheaper and effective.

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Background and Objectives: Industrial wastewater included the cyanide is one of the important sources of environmental pollution which founded in Industrial wastewater which are harmful for human health and environment. Therefore, the purpose of this research that was fundamental designed is investigation of Removal of cyanide from aquatic solution by using of iron and copper powder in experimental scale.
Material and Methods: At first, pilot was designed. Then, acquired pH optimum equal to 2,7 for copper and iron by variation pH= (2,4,6,8,12) and constant other parameters. The effect of initial cyanide concentration (40,60,80 mg/l), initial iron and copper dosage (0.08-1 g/100CC) and contact time (15-12 min) studied at the constant of optimum pH. 
Results: The result showed removal efficiency Increased from 46.6% to 90.56% and 31% to 93.78% for copper and iron by increasing of contact time from 15to 120 minute in constant conditions, respectively. Also result showed Removal efficiency decreased and increased by increasing initial cyanide concentration and initial iron and copper dosage. The results showed equilibrium data were explained acceptably by Langmuir isotherms and kinetic parameters were obtained by application of Langmuir&Hinshelwood equation.
Conclusion: The results showed that removal of cyanide can be quick and effective done by iron and copper in experimental scale.

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A MicrosoftInternetExplorer4 Background and Objectives: Colored wastewaters are known as one of the most important sources of environmental pollutants. Having toxic chemicals and aesthetic problems has made treatment of these wastewaters very crucial. So far a number of methods such as electrochemical treatment, coagulation and flocculation, and adsorption have been used for treatment of textile industries wastewater. Hence,  the efficiency of zero-valent iron powder in the presence of UV light and hydrogen peroxide to remove Acid Orange 7 and Reactive Black 5 from the synthetic solutions was investigated.
Materials and Methods: Conducting all experiments in a batch reactor, we examined different parameters including initial concentration of the color (25, 50, 75 mg/L), contact time (30,  60, 120 min), pH (3, 7, 11), the amount of iron powder (0.6, 1.3,  2  g/l), and hydrogen peroxide concentration (10, 15, 20  ml/l).
Result: The results showed that dye removal efficiency was increased by increasing contact time, the amount of iron powder and hydrogen peroxide concentration. On the other hand, with the increasing pH and initial concentration of dye, removal efficiency decreased in both AO7and RB5 dyes.
Conclusion: We found that the integrated ZVI/UV/H₂O₂ method has  high efficiency in removing azo dyes Acid Orange 7 and Reactive Black 5.

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Background and Objective: Electroproxone process is a combination of ozonation process and electrolysis in which the production of hydroxyl radical and ultimately degradation of a pollutant occurs. The aim of this study was to estimate the E-Proxone process in removing ceftriaxone from a synthetic solution.
Materials and Methods: In this experimental study, a semi-continuous reactor equipped with four graphene electrodes having 2 × 10 cm dimension and 3 mm thickness was used. The effect of pH (3-11), concentration of ozone gas (1-5 mg/min), direct electric current (1-3 A), initial concentration of ceftriaxone (5-50 mg/L) and radical scavenger dose (tertbutanol = 20 mmol/L) was studied in a 0-60 minutes reaction time. The Ceftriaxone concentration was measured by HPLC, COD was measured with spectrophotometer (DR6000) and TOC with a TOC analyzer.
Results: The results of this study indicated that this process had sufficient performance in the degradation of the antibiotic and diminishing of COD and TOC. The excellent condition was pH = 3, the electric current of 3 A, the ozone concentration of 5 mg/min, and the sodium sulfate as an electrolyte was 50 mmole/L. The ceftriaxone concentration was 5 mg/L in the duration of the 30 minutes experiment. 99.39% of the Ceftriaxone was destroyed. The process efficiency in COD and TOC removal was highest at 90 minutes. The presence of tertbutanol reduced the process efficiency to 83%.
Conclusion: The E-Proxone process, as one of the advanced oxidation processes, has the ability to reduce the pollution load of pharmaceutical industry, especially the ceftriaxone in this wastewater. This process is considered an environmentally friendly process.