Health and environment
Mousa Aminivafa; Ahmad Allahabadi; Golamreza Moussavi; Hosein Fahimi
Volume 28, Issue 6 , January and February 2022, , Pages 838-849
Abstract
Background and Objectives: Antibiotics, comprising a significant amount of pharmaceutical compounds, are used as human and veterinary treatments . these antibiotics come to appear as contaminantoin soil, surface water, groundwater, and even drinkingwater.Advanced oxidation processes such as catalytic ...
Read More
Background and Objectives: Antibiotics, comprising a significant amount of pharmaceutical compounds, are used as human and veterinary treatments . these antibiotics come to appear as contaminantoin soil, surface water, groundwater, and even drinkingwater.Advanced oxidation processes such as catalytic ozonation are effective to remove the antibiotics form water and wastewaterThe aim of this study was to investigate the efficiency of Catalytic Ozonation Process for tetracycline antibiotics removal from contaminated watersMaterial and method:In this design, an ozonation pilot with a volume of 200 cc was used. In each experiment, the tetracycline solution was poured into the desired concentration, the pH of the sample was adjusted with sulfuric acid and NaOH. At different times of 5 to 30 minutes and different pHs of 2 to 10 ozonation was performed at the dose of 0.8 mg/min. Then, under these conditions, ozonation was performed in the presence of activated carbon catalyst and a sample was discharged from the pilot and analyzed (HPLC) to determine the remaining tetracycline.Results:The results showed that under optimum conditions of pH= 8 and ozone dose of 0.8 mg / min and contact time of 30 minutes ozonation only eliminated 59% of tetracycline and in the same conditions catalytic ozonation with 0.01 g/L carbon. The Calligonum comosum tree was able to remove 100% tetracycline in 30 minutes.Conclusion: The results of this study showed that carbon catalyzed ozonation from wood Calligonum comosum waste can be used as an advanced treatment method.
Health and environment
Mahboube Eskandari; Nasser Goudarzi; Mansour Arab chamjangali; Seyyed Gholamreza Moussavi
Volume 27, Issue 2 , July and August 2020, , Pages 131-141
Abstract
ABSTRACTBackground: The photocatalytic process has been used for many years in industrialized countries as a solution to the world's environmental pollution. During the oxidative photo-catalytic processes, the pollutants are completely degraded by UV irradiation in the presence of semi-conductor catalysts, ...
Read More
ABSTRACTBackground: The photocatalytic process has been used for many years in industrialized countries as a solution to the world's environmental pollution. During the oxidative photo-catalytic processes, the pollutants are completely degraded by UV irradiation in the presence of semi-conductor catalysts, and are converted to CO2 and H2O. In this work, for the first time, the use of a 9-Watt UVC lamp with synthetic zinc oxide nanoparticles for degradation of atenolol is studied.Material and method: The main objective of this work is to investigate the effect of synthetic zinc oxide photo-catalyst on the rate of destruction of atenolol as an organic pollutant in wastewater using low-intensity UV light. The effects of parameters such as concentration of atenolol, amount of photo-catalyst, pH, stirring rate, atmospheric nitrogen, and presence of various ions are studied in the photocatalytic reaction.Results: An oxidation reaction is performed under the optimal experimental conditions, i.e. 20 mg L-1 of atenolol, 10 mg L-1 of the photo-catalyst, pH 7.0, and a stirring rate of 600 rpm. After 120 minutes of irradiation, atenolol was degraded completely. Kinetic studies under optimized conditions are shown pseudo- first order kinetic.Conclusion: The results of this study indicate the acceptable performance of the photocatalytic degradation process of synthetic zinc oxide nanoparticles and 9-watt mercury vapor lamp in the decomposition of atenolol.
Health and environment
Parisa Baratpour; Seyed Gholamreza Moussavi; Ahmad Alahabadi; Sakine Shekoohiyan
Volume 26, Issue 6 , March and April 2020, , Pages 797-807
Abstract
Background & Objective: With industrial development and population growth, the emerging contaminants enter into the natural water resources. Therefore, in this study Adsorption potential of NH4Cl-induced activated carbon (NAC) was investigated to remove antibiotic sulfanilamide from contaminated ...
Read More
Background & Objective: With industrial development and population growth, the emerging contaminants enter into the natural water resources. Therefore, in this study Adsorption potential of NH4Cl-induced activated carbon (NAC) was investigated to remove antibiotic sulfanilamide from contaminated water.Materials &Methods: The effect of operational conditions including solution pH, NAC concentration, sulfanilamide initial concentration and contact time were studied. Results: NAC and SAC had specific surface area of 1029, 1024 and mean pore volume of 2.64, 2.23nm, respectively. With increasing the NAC concentration to 1 g/L, sulfanilamide adsorption efficiency increased to 84.4% within 40 min. Then the adsorption slightly increased with the increase in the contact time to 120 min and reached to its maximum adsorption of 99.2%. The maximum adsorption percentage of sulfanilamide onto SAC under similar conditions reached to 49.2%. The kinetics analysis showed that experimental adsorption data for both NAC and SAC were best fitted to the pseudo-second-order model. The maximum adsorption capacity of sulfanilamide onto NAC and SAC, calculated by the Langmuir model, was 238.1 and 87/7 mg/g, respectively.Conclusion: Generally, these results showed that NAC was an efficient adsorbent with high removal efficiency for eliminating the antibiotics from the contaminated water streams
Fatemeh Rezaei; Seyed Gholamreza Moussavi; Alireza Riyahi Bakhtiari; Yadollah Yamini
Abstract
Objectives Type of adsorbent is the most important parameter to adsorb volatile organic compounds (VOCs) from the air stream. Application of a selective adsorbent could lead to the higher efficiency and lower costs in the adsorption processes. The current study aimed at investigating the efficiency of ...
Read More
Objectives Type of adsorbent is the most important parameter to adsorb volatile organic compounds (VOCs) from the air stream. Application of a selective adsorbent could lead to the higher efficiency and lower costs in the adsorption processes. The current study aimed at investigating the efficiency of manganese oxide impregnated on GAC support (MnO/GAC) to remove toluene from air stream. The efficiency of MnO/GAC and GAC absorbents for toluene removal were compared at the same experimental conditions.Methods The MnO/GAC preparation method was Sol-gel. Retention time (0.5, 1, 1.5, 2, and 4 seconds), inlet toluene concentration (100, 200, 300, and 400 part per million, by volume) and the temperature of the air stream (25, 50, 75, and 100˚C) were examined as the main functional parameters in the adsorption process.Results Breakthrough time of MnO/GAC adsorbent in comparison to that of the plain GAC increased 6% to 11% at the retention time of 0.5 to 4 seconds. Adsorption capacity of GAC and MnO/GAC increased 67.9% and 61.1% by increasing inlet toluene concentration from 100 to 400 ppmv, respectively. Breakthrough time of GAC and MnO/GAC decreased 57.9% and 59.6% by increasing inlet toluene concentration from 100 to 400 ppmv, respectively. Breakthrough time of GAC decreased from 41 to 26 hours by increasing the temperature of the air stream from 25˚C to 100˚C. Direct air temperature increase affected the MnO/GAC efficiency for toluene adsorption and the breakthrough time increased from 46 to 57 hours.Conclusion Results of the current study showed that MnO/GAC could be applied as a good substitution for GAC in the adsorption of VOCs from air streams.
Samaneh Ghodrati; Seyyed Gholamreza Mosavi; ahmad Allahabadi
Volume 22, Issue 3 , May and June 2015, , Pages 270-281
Abstract
Background: Removal of humic acids during water treatment is important because it can react readily with chlorine and produce carcinogen compounds. In this study, performance, kinetic and isotherm of humic acid (HA) adsorption onto NH4Cl-induced activated carbon (NAC) has been investigated and compared ...
Read More
Background: Removal of humic acids during water treatment is important because it can react readily with chlorine and produce carcinogen compounds. In this study, performance, kinetic and isotherm of humic acid (HA) adsorption onto NH4Cl-induced activated carbon (NAC) has been investigated and compared to the standard activated carbon (SAC).
Materials and Methods: NAC and SAC were used as the adsorbent in the present work and adsorption experiments were performed in batch mode. Adsorption of humic acid (HA) on SAC and NAC as a function of solution initial pH (2-10), adsorbent dosage (0.1-0.4 g/L), contact time (5-70 min), and adsorbate concentration (5-20 mg/L) was investigated.
Results: NAC exhibited higher HA adsorption capacity than that of SAC and HA adsorption capacities for both decreased with increasing solution initial pH in range of 2 to 10. The HA removal efficiencies of SAC and NAC were found to increase with increasing the adsorbent dosage. The adsorption kinetics data were well fitted by pseudo-second-order equation. The mechanisms of the adsorption of HA on SAC and NAC at pH 7 may include electrostatic attraction and hydrogen bonding. The adsorption isotherm data showed that adsorption behavior of HA well fitted by Langmuir adsorption isotherm for both NAC and SAC. The maximum adsorption capacity was 93.45 and 67.57 mg/g for NAC and SAC, respectively.
Conclusion: The results revealed that NAC has significantly removed HA from aqueous solutions compared to SAC and even many other adsorbents. Thus NAC as a cheap and more appropriate adsorbent can be used for removal of humic substances from polluted waters.
Mehdi Ghorbanian; Seyyed Gholamreza Mosavi; Zeynab Hosseini
Volume 22, Issue 1 , March and April 2015, , Pages 7-16
Abstract
Background: Removal of turbidity is essential due to its hygienic, environmental and aesthetics effects. Therefore, this study aimed to determine electrocoagulation efficiency in high seasonal turbidity.
Materials and Methods: This experimental study was conducted in bench scale. The electrochemical ...
Read More
Background: Removal of turbidity is essential due to its hygienic, environmental and aesthetics effects. Therefore, this study aimed to determine electrocoagulation efficiency in high seasonal turbidity.
Materials and Methods: This experimental study was conducted in bench scale. The electrochemical reactor was consist of cylindrical glass column having an internal diameter of 5 cm and a height of 51 cm and operated in the batch mode. Two sheets of aluminum spaced 2 cm apart were installed in the cell’s electrodes. The studied parameters was current density, reaction time and initial turbidity.
Results: Turbidity removal increased by reaction time, initial turbidity and current density. Regarding amount of produced sludge and economic aspects, reaction time of 2 min and current density of 3 mA/cm2 were selected as optimum conditions.
Conclusion: Results of present work indicated that the electrocoagulation process is capable to reduce high concentration of turbidity to permissible standard levels efficiently.
Kamyar Yaghmaiyan; Gholamreza Mousavi; Hamidreza Karimi; Ahmad Allahabadi
Volume 20, Issue 4 , January and February 2014, , Pages 573-582
Abstract
Background: Antibiotics are important pollutants of water resources, and because of hard biodegradability, they can be filtered through adsorption method. Activated carbon is one of the best adsorbents. The aim of this study was to investigate the amoxicillin removal rate of a standard granular activated ...
Read More
Background: Antibiotics are important pollutants of water resources, and because of hard biodegradability, they can be filtered through adsorption method. Activated carbon is one of the best adsorbents. The aim of this study was to investigate the amoxicillin removal rate of a standard granular activated carbon.
Materials and methods: The adsorption experiments were conducted in the stirred (100 rpm) glass reactor. In each test, 50 ml of aqueous solution contaminated by amoxicillin was transferred into the reactor, and the influence of adsorbent dose, adsorbent type, amoxicillin concentration, reaction time, solution pH and temperature was tested on the amoxicillin adsorption. At the end of each of adsorption tests, the suspension was filtered using a cellulose acetate filter with 0.45µm pore size and the filtrate was analyzed for residual amoxicillin using HPLC.
Results: The obtained data showed that the best conditions for removal of amoxicillin from contaminated water using granular activated carbon were as follow: pH: 6, adsorbent concentration: 1.6 g/l, reaction time: 60 min, temperature: 25oc. In these conditions up to 86% of amoxicillin (concentration: 50 mg/l) could be adsorb by a granular 16-20 activated carbon.
Conclusion: Adsorption onto activated carbon is an efficient method for the removal of non-degradable water pollutants such as antibiotics and toxins.
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 ...
Read More
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