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The combination process of UV/ S2O82-/Al2O3 leads to the production of radicals and radical hydroxyls, which could decompose and remove various pollutants, such as phenol. The present study aimed to investigate the photocatalytic efficiency of aluminum oxide nanoparticles and persulfate compilative processes in the removal of phenol. This experimental study was conducted in a discontinuous reaction chamber with a useful volume of one liter. In this process, we assessed the effects of the initial pH parameters (3, 5, 7, and 9), initial concentration of phenol (10, 20, 30, 50, and 100 mg/l), concentration of persulfate anions (20, 30, 40, 50, and 60 mg/l), reaction time (5 and 120 minutes), and dose of Al2O3 nanoparticles (10, 20, 30, and 40 mg/l). The applied pilot was composed of a low-pressure mercury lamp (55 Watt), which was inside the steel chamber. The obtained data were fitted to the pseudo-first- and pseudo-second-order reaction kinetics. According to the findings, the process had high efficiency in the removal of phenol. In optimal conditions (pH:5, persulfate concentration: 50 mg/l, nanoparticle dose: 40 mg/l, reaction time: 60 minutes), the efficiency of the process was determined to be 95% at the initial phenol concentration of 10 mg/l, which was fitted with first-rate kinetics (R2=0.98). Furthermore, the highest efficiency was observed in the photocatalytic process of aluminum oxide nanoparticles and persulfates in the optimal conditions of exploitation. Therefore, persulfate could be used as an appropriate oxidizer with aluminum oxide nanoparticles for the removal of phenol.

Background: Dyes are resistant organic matter because they have an aromatic rings. Sulfate radical (SO4●-) is a powerful oxidative radical. The design via CCD, cause the process was done by high accurate and low-cost. The aim of this study was modeling of UV-EPS process to degradation of Acid Blue 25 dye via the CCD from aqueous. Methods: In this experiment study, used to a photoelectrochemical reactor with two iron electrodes as an anode and two titanium electrodes as a cathode and Low-pressure mercury lamp (254 nm). The pH (2-4), Direct Current (0.75-1/5 A), S2O82- concentration (0/5-1/5 mg/l), reaction time (20-40 min) and initial concentration of AB25 (50 -100 mg/l) as a main independed variables were chosen. Also, COD, synergist effect, presence of radical scavenger and kinetic of reaction were studied in optimum conditions. Dye concentration and COD were measured by spectrophotometer (DR5000). Results: The results illustrate that the efficiency of process is affected by the variables. Optimum condition obtained in pH=3/01, DC was 1/08 A, PS was 1/30 mg/l, reaction time was 34 minute and initial concentration equal to 50 mg/l. In this situation efficiency of process was 91 percent. The COD removal in these conditions was 69 percent. The correlation coefficient was 0.84 which indicates that the quadratic model is suitable for process design. The kinetics of reaction followed the first order kinetics. Reduce of efficiency of process in the presence of radical scavenger occur. Conclusion: Optimizing via CCD reduces the number of runs and increases accuracy. This process has a high efficiency in dye and COD removal and this process can be used to reduce the pollutant loading form industrial wastewater, such as textile wastewater, before discharging into the environment.

Background and Objectives: Using additives such as Balnkit, to increasing the quality color of food and for the fermentation and early preparation of bread dough, has increased in recent years. The purpose of this study was to investigate the concentration of Blankit in Hamadan breads production and risk assessment of food consumption during 2016. Materials and Methods: In this descriptive-analytical study, Balnkit, concentration in breads produced in Hamadan in 2016 was determined. A total number of 85 samples were randomly collected from all bakeries in two steps. The concentration of Blankit was determined according to ISIRI guideline using spectrophotometer in 560 nm. Then for the evaluation of risk assessment of food consumption, the value of target hazard quotients (THQ) was calculated. Results: The Blankit was not found in 97% of samples and only 3% of samples (Lavash bread) have the Blankit. The calculation of the THQ index showed that value of THQ was 0.0041 whose value is less than 1 and the consumption of bread with this concentration will not endanger. Conclusions: The results of this study showed that the addition of Blankitin bread processing, with regard to the concentrations determined and eliminating it from bread due to the heat, does not pose a threat to the health of the people.