Showing 16 results for Rezaee
M Farzadkia, R Rezaee Kalantari, S Jorfi, A.r Talaee, G.r Moussavi,
Volume 2, Issue 1 (16 2009)
Abstract
Background and Objectives : Propylene glycol is the main compound of anti-freezing chemicals. A significant amount of propylene glycol is released to the environment after application and contaminates the soil. The main objective of this study was to determine the biological removal of propylene glycol from wastewater and its degradation in soil by the isolated bacteria from activated sludge process.
Materials and Methods: In the present study, the sludge taken from the return flow in a local activated sludge treatment system was used as the initial seed. The performance of the bioreactor in treating the wastewater was evaluated at four different retention times of 18, 12, 6 and 4 h all with the inlet COD concentration of 1000 mg/L. This phase lasted around 4 months. Then, a part of the adapted microorganisms were transported from the bioreactor to the soil which was synthetically contaminated to the propylene glycol.
Results: The average of propylene glycol removal efficiency from the wastewater in detention times of 18, 12, 8 and 4 h in steady state conditions was 98.6%, 97.1%, 86.4% and 62.2% respectively. Also, the maximum degradation in soil was found to be 97.8%.
Conclusion: According to the results obtained from this study, it appears that propylene glycol is inherently well biodegradable and can be biodegraded in liquid phase and soil after a short period of adaptation.
H Masombaigi, A Rezaee, A Nasiri,
Volume 2, Issue 3 (25 2009)
Abstract
Backgrounds and Objectives: Textile industrial wastewaters are one of the important sources of environmental contaminants. In the recent years, use of advanced oxidation processes, by producing highly active and reactive components such as hydroxyl radicals has been proposed. The aim of this research is photocatalytic degradation of methylene blue dye using the ZnO-nanoparticle with UVA irradiation.
Materials and Methods: photocatalytic degradation of methylene blue color using the ZnO- nanoparticles excited with UVA irradiation. In this research, photocatalytic degradation of methylene blue dye was study using different concentration of ZnO-nanoparticles under UVA irradiation in a batch reactor.
Results: The results of this research show that removal of methylene blue dye has direct correlation with UVA intensity. The best results of dye degradation were reported in concentration of 150 mg/L ZnO nano-particles and the radiation intensity of 240 µW/cm2. Rate of dye removal was decrease with increasing of color concentration. Subsequent of color degradation, the initial COD were decresed by %60.
Conclusion: The photocatalytic degradation process using ZnO nano-particles under UVA irradiation could be remove the methylene blue dye and 60% of COD.
H Godini, A Rezaee, F Beranvand,
Volume 3, Issue 2 (6 2010)
Abstract
Backgrounds and Objectives: Nitrate is a water contaminant that can cause health problems in human and animals, in addition to eutrophication of the water body. So, Nitrate-contaminated water may be treated by treatment systems. In this study, hydrogenotrophic denitrification using hydrogen produced by Fe0 as an electron donor to nitrate removal was evaluated to assess the feasibility of employing Fe0 in the biological nitrate treatment.
Materials andMethods : Batch experiments were conducted using 250 ml amber bottles at 20-35oC under anoxic conditions. The nitrate concentration in each reactor was 20 mg N/L and triplicate samples were prepared for the following treatment: Fe0 plus cells, Fe0 only, and control. The effect of Fe+2 and temperature on nitrate reduction was evaluated.
Results : 97 percent of Nitrate was reduced within 2 day in a Fe0-cell reactor, while only 30% of the nitrate was abiotically reduced over 2 day at 30 oC. Fe+2, which is produced during anaerobic iron corrosion in the Fe0-cell system, might act as an electron donor for nitrate. Abiotic reduction and microbial reduction of nitrate was significantly affected by temperature conditions. The reduction rate decreased as the temperature deceased.
Conclusion:This study demonstrated the potential applicability of employing Fe0 as a source of electrons for biological nitrate reduction. Use of Fe0 for microbial nitrate reduction can obviate the disadvantages associated with traditional biological denitrification that relies on the use of organic substrates or explosive hydrogen gas.
M Pirsaheb, A Almasi, M Rezaee,
Volume 3, Issue 3 (4 2010)
Abstract
Backgrounds and Objectives:The food handling employee education program improves food safety. Determining knowledge, attitude and practice (KAP) level of workers who prepare, distribute and sale the food products make easy to control food safety. This study aimed to evaluate effects of intensive food safety education course on KAP of food handlers. in Kermanshah.
Materials andMethods: Knowledge, attitude and practice of 370workers of variety of food handling fields were studied before and after educational intervention course.Avalidated questionnaire about knowledge, attitude based on instruction from Ministry of Health and Medical Sciences for food handling was used for data collection. Paired t-test and Χ2 were applied for statistical analysis.
Results: The results showed positive effects of education program on KAP of food handlers. There was significant increase in knowledge marks before and after intervention, 20.5+ 4.03 vs. 23.73 + 3.75 (p<0.001).Attitude and practice of participants were increased significantly before 107.2+14.6 43.93+7.6 compared to after 112.23+14.5 46.11+8 intervention respectively (p<0.001). The most increased mark of KAP was belonged to 21-30 years age group.
Conclusion: Our findings confirm that educational intervention improved KAP of food handlers. To increase food safety, running periodical educational courses for the same filed workers with final exam and providing certificate highly recommended.
A Rezaee, G Kashi, A Jonidi Jafari, A.r Khataee,
Volume 4, Issue 2 (9 2011)
Abstract
Background and objective: The conventional chemical and physical methods for water disinfection include the application of ultraviolet (UV), chlorination, and ozonation. Water disinfection by electrochemical methods has been increasingly carried out recently. The goal of this applied - analytical research is to investigate the removal of E. coli bacteria, as the index of water microbial contamination, from drinking water by electrochemistry method.
Materials and Methods: In this study, the contaminated water sample was prepared through adding 102 and 103 E. coli bacteria per ml of drinking water. The contaminated water entered into the electrochemical reactor and different conditions were studied, included pH (6, 7, and 8), number of bacterium (102 and 103 per milliliter), time (5, 10, 20, and 40 min), distance between electrodes (2,2.5, 3, and 3.5 cm), and voltage (10, 20, 30, and 40 volts).
Results: The findings indicated the indirect correlation between bacteria removal efficiency and the variable distances between two electrode. The results indicated the direct correlation between bacteria removal efficiency and the variables voltage and electrolysis times. The results showed that the best conditions for removal of 102 and 103 bacteria per milliliter obtained at pH 7, electrolysis time of 10 min, distance between electrodes 2 cm, in the voltage 20 and 30 volts, respectively.
Conclusion: The results of this study indicate that voltage and electrolysis time have the most significant effect on electrolysis efficiency. Research findings showed that electrolysis is a promising method for removal of E. coli bacterium from drinking water.
Ruhollah Rostami, Ahmad Jonidi Jafari, Roshanak Rezaee Kalantari, Mitra Gholami,
Volume 5, Issue 1 (6 2012)
Abstract
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MicrosoftInternetExplorer4 Background and Objectives:Benzene,
toluene and Xylenes (BTX) are organic pollutants, which are mainly associated
with oil and its derivatives. BTX is environmental contaminants and considered
harmful to human health. Application of surface absorbents such as zeolite is
one of several methods for the removal of these compounds. In this study,
BTX compounds'
removal efficiencies were
investigated and compared by using
clinoptilolite
type zeolite
and zeolite
with copper
oxide nanoparticles.
Materials
and Methods: In this study, the modified zeolite by
hydrochloric acid in the grain size 1-2 mm and modified zeolite with nano
particle of copper oxide were used. Artificially- Contaminated Air
flow was used
continuously .To determine
BTX concentrations,
samplings were done by charcoal tube in
current input and output. The
concentrations of contaminants were determined by gas chromatography with FID
detector.
Results: Removal efficiency of benzene,
toluene, p-xylene, m-xylene and o-xylene by clinoptilolite were 78.3%, 62.1%,
32.2% 32.15% and 18.8%, respectively. For the clinoptilolite
containing copper oxide nano particles efficiency were 25.42%, 35.65%, 36.33%,
33.24% and 29.39%, respectively. Average removal efficiency of BTX compounds
observed when the zeolite without nanoparticles used (43.31%) was more than
zeolite with nanoparticles (32%). The results showed that the concentration of
CO2 in the outlet air of the zeolite-containing nanoparticle (550
ppm) was more than the zeolite without nanoparticle (525 ppm).
Conclusion: Results showed that adding nanoparticles to the
zeolite, although the removal efficiency of benzene and toluene
can be reduced.
The results showed that adding
nanoparticles to the zeolite, although can be reduced removal efficiency of
benzene and toluene, which may be due to occupying or blocking of the pollution
absorption sites by the nanoparticles on the zeolite, but It cause promote more
catalytic effect of zeolite in the decomposition process of contaminants by
breaking the molecules of pollutants and their further degradation progress is
done for conversion to carbon dioxide
Mahmood Alimohamadi, Ebrahim Molaee Aghaee, Ramin Nabizadeh Nodehi, Gholam Reza Jahed, Sasan Rezaee, Akbar Goldasteh, Shahrokh Nazmara, Hassan Aslani,
Volume 5, Issue 2 (13 2012)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: Heavy metals including antimony and cobalt as two
contaminant factors leach from polyethylene terephthalate packages into water
under some conditions. Therefore, their detection was concerned at different
storage conditions.
Materials and Methods: Five time-temperature treatments were carried out for 5 water samples. Storage
conditions were defined as following: at outdoor and sunlight ambient
temperature, room temperature, and at 40˚C at different intervals for 8 weeks,
at 65˚C for 6 weeks and 80˚C for 7 days. Detection was performed by ICP-AES
method and the data analysis was processed by SPSS software.
Results: Antimony
concentration increased by storage time at all temperatures and for all
samples, however enhancing proportion was different in samples. At outdoor,
40˚C and room temperature, concentration increase was below the MCL by the end
of storage period. But at 65˚C and 85˚C, antimony concentration exceeded MCL by
study time and the difference between samples 4 and 5, for example, was
significant (p≤0.05). Cobalt concentration at the beginning and during the
study was also too less and lower than the detection limit.
Conclusion: By
increasing temperature and time, leaching of antimony into water increases.
Moreover, sunlight has effect but not noticeable at the temperature of present
study. In this study, blue or clear packaging had no significant effect on
antimony leakage (P>0.05).
Afshin Maleki, Amir Hossein Mahvi, Reza Rezaee, Behrouz Davari,
Volume 5, Issue 4 (15 2013)
Abstract
Background and Objectives: Dyes are an important class of pollutants, which can even be identified by naked eye. Disposal of dyes in precious water resources have been prohibited, however, various treatment technologies are in use. Among various methods adsorption occupies a prominent place in dye removal. Therefore, natural zeolite (clinoptilolite) and acid modified zeolite were used as a low-cost adsorbent to evaluate their ability to remove color from aqueous solution using a batch adsorption experiments.
Materials and Methods: Modification of zeolite surface was carried out with two acids sulfuric acid and phosphoric acid, to improve the removal efficiency of reactive blue 19. We studied the influence of acid concentration, contact time, solution pH, initial dye concentration, and adsorbent dosage on the removal efficiency.
Results: The parameters of Langmuir and Freundlich adsorption isotherms have been determined using the adsorption data. Equilibrium adsorption data followed both Langmuir and Freundlich isotherms. It was also found that adsorption of dye by zeolite followed pseudo first-order kinetics. The adsorption results indicated that natural zeolite has a limited adsorption capacity for reactive dye but can be distinctly improved by modifying its surfaces with acid. Experimental results also showed that sulfuric acid has better performance than phosphoric acid in the modification of zeolite for dye adsorption.
Conclusion: We achieved the best results in terms of removal efficiency (41-72%) for the zeolite modified with Si/Al ratio of 7.5 after 3 h of contact.
َahmad Joneidi Jafari, Ayooob Rastegar, Mahdi Farzadkia, Roshanak Rezaee Kalantary, Zahra Rezaee Gozalabad,
Volume 6, Issue 4 (3-2014)
Abstract
Background and Objective:Application of compost containing heavy metals can increase the concentration of metals in soil and groundwater. Therefore,the aim of this study was to investigate leaching lead, chromium,and cadmium from three soils (a sandy loam, a sandy clay loam and silt clay loam) amended with compost from the municipal solid waste. Material andMethod:First, the selected soils were repacked into columns (with an inner diameter of 100mm and a height of 600mm). Treatments included(a) low metal content compost (LMCC), (b) enriched metal content compost (EMCC) and (c) control. Then soil columns were incubated at room temperature for 9 days and were irrigated daily with deionized water to make a total of a 250 mm. Leachates were collected and analyzed for pH, EC, Pb, Cr, and Cd concentration. Results: It was found that the application ofEMCCwas significant (p≤0/05) on reducing pH, increasing electrical conductivity and leakage of metalscompared withcontrolin all three soils. But application of LMCC was not significant (p≥0/05) on the metals leaching compared withcontrolin all three soils. The overall quantities of metals leached followed the sandy loam> sandy clay loam> silt clay loam. Conclusion: The concentration of metals in the leachates depended on the soil characteristics and on the type of compost added to the soil. Therefore,application of enriched metal content compost on the soils containinga high percentage ofsandmay pose a risk in terms of groundwater contamination with heavy metals.
S. Jorfi, A. Rezaee, N. Jaafarzadeh Haghighifard, G.a Moheb-Ali,
Volume 7, Issue 3 (5-2014)
Abstract
Background and objectives: Because of problems dealing with bioremediation including being time consuming, low efficiency and toxicity to biota, application of advanced oxidation processes with higher efficiency and shorter remediation time have been considered for removal of hydrophobic hydrocarbons from contaminated soils. A great interest has been directed to Fenton oxidation because of its simplicity and high oxidation potential. The objective of this study was to determine the Fenton-like oxidation efficiency for pyrene removal from soil using iron nano oxides and Fe2+. Material and Methods: The H2O2/Fe molar ratios of unadjusted with native Fe content of soil, 10, and 20 H2O2 concentrations of 0 – 500 mM pH 3, 5, and 7 and soil samples containing Fe2+, native iron and iron nano oxides were investigated for removal of 100 mg/kg pyrene according to Taguchi experimental design. Results: Fe2+, H2O2/Fe molar ratio of 20, pH 3 and H2O2 concentration of 500 mM were determined as optimum conditions. Under optimum conditions, S/N ratio increased to 39.322 and the pyrne removal reached to 86 % for Fe2+ and 83 % for Fe3+ respectively, after 2 hours of reaction time and pH 3. Conclusion: Fenton oxidation using iron nano oxides under defined optimum conditions and neutral pH, can be a suitable alternative to conventional Fenton for remediation of soils contaminated with pyrene.
B. Kakavandi, M. Mokhtari, R. Rezaee Kalantari, E. Ahmadi, N. Rastkari, M. Fatehi, A. Azari,
Volume 7, Issue 3 (5-2014)
Abstract
Background and Objectives: Phenol is one of priority pollutants produced through leather, paint, resin, and pharmaceutical industries and it can contaminate groundwater after entering to the environment. Hence, it is necessary to use a suitable method for its removal. The aim of this study was synthesize and efficiency evaluation of magnetic nanocomposite of activated carbon powder-zero valent iron/silver (PAC-Feo/Ag) in the removal of phenol from aqueous solution. Material & Methods: Reduction method was used for converting bivalent iron to zero valent iron and co-precipitation method for depositing of iron on activated carbon. For coating silver on nano zero valent iron, rapid mixing at high temperature was used. The adsorbent was characterized using SEM, TEM, and XRD techniques. Then, the impact of pH, contact time, agitation speed, temperature, adsorbent, and initial phenol concentration were evaluated and optimized by one factor at the time method. Reaction kinetics and isotherms were also determined. Results: It was found that PAC-Feo/Ag has cubic and intertwined structure and has a diameter in the range from 40 to 100 nm. The optimum conditions for phenol removal by PAC-Feo/Ag were as pH=3, 90 min contact time, 200 rpm agitating speed and adsorbent concentration equal to 1 g/l. Isotherm and kinetic equations showed that the experimental data of phenol adsorption onto PAC-Feo/Ag are correlated to the Langmuir (R2>0.969) and pseudo-second order (R2<0.965) models, respectively. Conclusion: Under optimum conditions, modified adsorbent by zero valent iron and silver with maximum efficiency of 97% has quickly and effectively ability in removal of phenol and it can be easily separated from the solution sample by magnet because of its magnetic properties.
A Mogadam Arjmand, M Rezaee, S Naseri, S Eshraghi,
Volume 8, Issue 1 (8-2015)
Abstract
Background & Objectives: Cryptosporidium parvum is considered as one of the pathogenic agents transmitted by water, high resistance to conventional disinfection methods, and potency of creating various problems in water resource. Because of various problems in Cryptosporidium parvum studies, Bacillus subtilis spore is recommended as a surrogate organism for studying protozoa inactivation and evaluation of water quality. On the other hand, electrochemical process is presented as an environmental friendly and high efficient method in disinfection in recent years. The aim of this study was to propose a method for promotion of the water quality. Materials & Methods: In this study, the electrochemical system used was consisted of steel electrodes (4×8 cm), 200 mL volume, and 1-4 mg/L sodium chloride. The bacterial suspensions of Bacillus subtilis (ATCC 6633) was prepared according to the McFarland method with 103 to 106 spores/mL concentration. The microbial agent removal was evaluated by sampling and transferring water to the tripticase soy agar medium every 15 min for 60 min. The number of bacteria spores, supporting electrolyte, induced current, and reaction time were evaluated. Results: The proposed electrolysis process could not eliminate Bacillus subtilis spores at 104 to 106 spores mL-1 rate at lower than 100 mA current for 60 min. Adding sodium chloride supporting electrolyte up to 4 mg/L concentration completely eliminated Bacillus subtilis spores after 60 min. Conclusion: Adding sodium chloride as a supporting electrolyte can increase the spore removal because of increasing direct and indirect oxidation in electrolysis process. Improving water disinfection and spore removal after 60 min could be described by higher oxidant agents in anode electrode.
M Gholamdokht Bandari, P Rezaee, Z Gholamdokht Bandari,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: Water quality assessment is an important step for optimal and proper use of water resources for drinking and selection of suitable and consistent water quality patterns. Therefore, the necessity of studying water quality characteristics in water resource management programs has been highly considered.
Materials and Methods: In this study, the hydrogeochemical quality of groundwater resources in the Siahoo region of Bandar Abbas was studied for drinking, agricultural and industrial purposes. Qualitative parameters of three wells, three springs, one juicy aqueduct and one surface water sample were used as input data. Water quality characteristics and charts were evaluated using Aq.qa and AquaChem software.
Results: Groundwater of the studied area was in the category of very hard water. According to the PIPER chart, the dominant hydrochemical facies were sulfatecolic and chloroformate species. According to the Willcox and Schuller qualitative index, groundwater for agricultural use was moderate and was acceptable for drinking water. In terms of the saturation index of islands, the existing water resources are corrosive to the sediment.
Conclusion: The data of this study indicate that one of the problems of the available water resources in Siahoo region is the high amount of salt and soluble materials, which show the effect of geological formations (evaporation, Chile, carbonates) and salt domes on the groundwater resources and reduction of the quality of water resources.
Zohreh Akbari Jonoush, Abbas Rezaee, Ali Ghaffarinejad,
Volume 15, Issue 2 (8-2022)
Abstract
Background and Objective: This study aimed to provide an effective electro-catalytic system for the simultaneous reduction of nitrate and disinfection of contaminated water by the electro-catalytic performance of Ni-Fe/Fe3O4 cathode.
Materials and Methods: At first, the Ni-Fe electrode was synthesized by the electro-deposition process. Then its physical properties were analyzed by scanning electron microscopy (FESEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, and photoelectron X-ray spectroscopy (XPS). Simultaneous disinfection and reduction of nitrate were performed under the following conditions: 15 mg Fe3O4 nanoparticles, pH 6.5, NaCl 10 mM, 50 mg/L nitrate, 105 CFU/mL and current density 4 mA/cm2.
Results: According to the results obtained in the absence of nitrate, 100 % of Escherichia coli bacteria were disinfected after 12 minutes. In the presence of nitrate, the time of complete disinfection increased to 120 minutes. In the absence of bacteria, 83% of nitrate was removed in 240 minutes, and in the presence of bacteria, the nitrate reduction efficiency increased slightly to 88%. In the nitrate reduction process, nitrite (0.22 mg/L) and ammonium (3.6 mg/L) were produced. In the presence of bacteria, the amounts of nitrite and ammonium produced increased to 0.42 mg/L and 7.3 mg/L.
Conclusion: The results show the outstanding ability of Ni-Fe/Fe3O4 electrode in electro-catalytic reduction of nitrate and disinfection of contaminated water separately and simultaneously with high efficiency and high selectivity to nitrogen.
Sara Ghayour, Abbas Rezaee, Mohsen Heidari,
Volume 16, Issue 1 (6-2023)
Abstract
Background and Objective: Agricultural lands around Tehran may become contaminated due to their proximity to pollution sources and such pollution should be investigated. Therefore, the main objectives of this study were to determine the pollution levels of some trace elements in the agricultural soils around Tehran and to assess the attributed health risks.
Materials and Methods: In this study, 43 soil samples were collected from agricultural lands around Tehran. The soil samples were prepared and acid-digested and the concentrations of Vanadium (V), Lithium (Li), Lanthanum (La), Molybdenum (Mo), and Antimony (Sb) were measured by ICP-OES. Based on the concentrations of the elements in soil, the pollution indices and non-carcinogenic risk (based on Monte Carlo simulation) were assessed.
Results: Among the studied elements, V had the highest concentration (131 mg/kg) followed by La > Li > Sb > Mo. The values of the geoaccumulation index (Igeo) and enrichment factor (EF) were in the ranges of -1.9 to 0.8 and 0.5 to 3.1, respectively. The Nemerow integrated pollution index (NIPI) values were in the range of 1.3 to 2.0. The values of non-carcinogenic risk for Li, Mo, Sb, and V were negligible, but it exceeded the threshold limit for La.
Conclusion: This study showed that the agricultural lands around Tehran are contaminated with studied trace elements to a low to moderate extent. However, an unacceptable non-carcinogenic risk attributed to La was estimated. Therefore, it is essential to pay special attention to the La pollution of agricultural soils around Tehran.
Fateme Rezaee, Meisam Rastegari Mehr, Ata Shakeri,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Water resources deficiency has caused the use of effluents to be considered as a source for re-use in the form of haloculture projects. An attempt has been made to investigate the possibility of using effluent produced by sugarcane production companies in the implementation of haloculture projects, from the viewpoint of the most used pesticides.
Materials and Methods: Ten water, four sediment, two plant, and two fish samples were analyzed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) to determine the concentration of pesticides. In order to assess the ecological risk, toxic unit (TU) and risk quotient (RQ) were calculated.
Results: Glyphosate and Ametryn in all liquid, solid, and biological samples had concentrations below the detection limit. 2.4.D, Metribuzin, and Atrazine had detectable concentrations in the samples. However, their concentrations are lower than the standard values. Metribuzin and Atrazine had high concentrations in the stems and leaves of reeds in the region, which may indicate the role of these plants in the remediation of water and sediment from these compounds.
Conclusion: Using effluent from Amirkabir and Mirzakouchak Khan agro-industrial complexes to implement the haloculture project does not pose a particular problem from the viewpoint of contamination with the studied pesticides. This is confirmed due to the small concentrations of the studied compounds in the liver and below the detection limit in the muscles. However, it is necessary to carry out more studies to evaluate the quality of effluent in terms of the other types of pollution.
