Health and environment
Khadijeh Yari; Mostafa Leili; Hassan Zolghadrnasab; Shima Mohammadi bolban; Shahla Rahmani
Volume 27, Issue 1 , May and June 2020, , Pages 93-100
Abstract
Background: The consumption of bottled water in various parts of the world have significantly increased. The aim of this study was to evaluate the physical, chemical and microbial quality of bottled waters in Hamadan in 2016.Materials and Methods: This research is a descriptive cross-sectional study, ...
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Background: The consumption of bottled water in various parts of the world have significantly increased. The aim of this study was to evaluate the physical, chemical and microbial quality of bottled waters in Hamadan in 2016.Materials and Methods: This research is a descriptive cross-sectional study, that was carried out on 5 popular brands and 40 randomly selected samples, in which 20 types of physical, chemical and microbial characteristics were investigated. All data were analysed using the statistical software package, SPSS 20.0 and descriptive statistics.Results: The results showed that none of the samples had microbial contamination and passed the required standards. Total dissolved solids (TDS) content are lower than the minimum values required by the Food and Drug Administration (500 mg/L). The differences between the measured and labeled values was investigated using paired t-test. Based on the results, there were differences between the measured and labeled values for all parameters, where for the parameters of nitrite, TDS and chloride it was significant, while for the rest of the parameters it was not significant. The mean values of the parameters were also compared with the standard values using one sample t-test. Conclusion: For the most samples, the assessed parameters were consistent with the standards, however, for the few number of samples which violates from the standard values it was also important in terms of the possible health impacts, thus should be taken into consideration.
Health and environment
Alireza Rahmani; Mostafa Leili; Jamal Mehralipor; Marzihe bagheri; Amir shabanloo; sonia chavoshi
Volume 26, Issue 2 , July and August 2019, , Pages 225-232
Abstract
Background: The use of (advanced oxidation processes) AOPs, due to have high performance in degradation of organic compounds is growing. Combined use of electrical current and sulfate free radical creates a synergy effect on removal of pollutant. The aim of this study was to evaluation the performance ...
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Background: The use of (advanced oxidation processes) AOPs, due to have high performance in degradation of organic compounds is growing. Combined use of electrical current and sulfate free radical creates a synergy effect on removal of pollutant. The aim of this study was to evaluation the performance of activated per sulfate by the electrochemical method with copper – iron electrodes for removal of Aniline from aqueous solution.Materials and Methods: In this experimental study, a batch electrochemical reactor with a useful volume of 250 mL, copper and iron electrodes with 2×10×50 mm area from the DC source to aniline degradation was used. Also the Influence of parameters such as pH, Voltage (with amper), initial concentration of per sulfate and initial concentration of Aniline was investigated. Aniline concentrations, determined by spectrophotometer DR5000 making HACH.Results: The experimental results indicated that the removal of aniline was influenced by different operational parameters, So that the highest process efficiency was obtained at pH 4, a voltage of 11 V, a concentration of per sulfate anions equal to 750 mg /L and a concentration of 60 mg /L of pollutant, 90.41% in a 25 minute period. It was also found that with an increase of nitrogen gas, efficiency will be increase and aeration reduces efficiency.Conclusion: The present study demonstrated the proper performance of the process in removing organic pollutants under optimal conditions of use as well as an alternative technology for the treatment of industrial wastewater containing Aniline.
Bahman Ramavandi; Mostafa Leili
Volume 21, Issue 3 , July and August 2014, , Pages 502-513
Abstract
Background: Dyes are used in many industries. The discharge of colored wastewater and effluents from these industries to receiving water bodies could cause many significant problems such as increasing the toxicity and chemical oxygen demand (COD). So, these types of wastewater should be appropriately ...
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Background: Dyes are used in many industries. The discharge of colored wastewater and effluents from these industries to receiving water bodies could cause many significant problems such as increasing the toxicity and chemical oxygen demand (COD). So, these types of wastewater should be appropriately treated. The efficiencies of activated carbon derived from date stone in the removal of methylene blue (MB) from aqueous solutions were assessed in this study.
Material and Methods: In this research that was an experimental study and was done in laboratory scale, the effects of different parameters such as initial pH (2-12), adsorbent dose (0.25-5 mg/L), initial dye concentration (50 -400 mg/L), and contact time (20-430 min) on methylene blue adsorption with activated carbon derived from date stone were evaluated. The reaction isotherm using the appropriate equations was also investigated.
Results: The results showed that dye adsorption with high efficiencies were obtained at pH 8. The evaluation of adsorption isotherm showed that laboratory data was best fit with Langmuir isotherm (R2= 0.998) and maximum adsorption capacity was obtained 478.3 mg/g.
Conclusion: Based on the removal efficiency of used MB-concentrations in this study, we found that activated carbon derived from date stones could be applied as an efficient and inexpensive adsorbent in the removal of dyes from wastewater.
Maryam Ghaffari; Kazem Nadafi; Seyyed Gholamreza Mosavi; Mostafa Lieli
Volume 20, Issue 1 , March and April 2013, , Pages 51-61
Abstract
Background: Furfural is a toxic chemical, so, to avoid its effects on humans and the environment, furfural-containing wastewater must be treated with an appropriate method prior to dispose in the environment. In this study, advanced oxidation methods based on ozone was used to removal of various concentrations ...
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Background: Furfural is a toxic chemical, so, to avoid its effects on humans and the environment, furfural-containing wastewater must be treated with an appropriate method prior to dispose in the environment. In this study, advanced oxidation methods based on ozone was used to removal of various concentrations of furfural in laboratory scale.
Materials and Methods: This study is an applied research and the required samples was taken in desired times. The effects of single ozonation process (SOP), catalytic ozonation process (COP), and single adsorption on activated carbon (SAP) on furfural removal efficiency in different conditions were studied. Results: In this study, the influence of some important parameters such as pH, activated carbon dosage and reaction time on the efficiency of SOP, SAP and COP was studied. In the case of pH, the results showed that the efficiency of all three processes in very acidic and very alkaline conditions were higher than the other pH. By increasing activated carbon dosages, the removal efficiency was also increased. Finally, the removal efficiency for the processes studied, increased by increasing reaction time. Conclusion: The higher removal efficiency of furfural in acidic conditions can be due to direct and catalytic oxidation of furfural by ozone. Higher efficiency in the alkaline pH may be due to indirect oxidation because of hydroxyl radicals generation. About the effect of reaction time, the removal efficiency of COP indicates that there was a synergistic effect in catalytic ozonation processes. The increase of reaction surfaces available for ozone-activated carbon-furfural reactions could be the reason of increased efficiency with increasing dosages of activated carbon