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Showing 6 results for Gholizade
Effectiveness of Rice Husk Ash in Removal of Phenolic  Compounds from Aqueous Solutions, Equilibrium  and Kinetics Studies
Majid Kermani, Mitra Gholami, Abdolmajid Gholizade, Mahdi Farzadkia, Ali Esrafili,
Volume 5, Issue 1 (6 2012)
Abstract
MicrosoftInternetExplorer4 Background and Objectives: Phenols in trace quantities are usually present in the treated effluent of many wastewater-treatment plants. Phenol compounds even at low concentration can cause toxicity, health and significant taste and odor problem in drinking waters. This research focuses on understanding the sorption process and developing a cost-effective technology for the treatment of water contaminated with phenolic compounds, which are discharged into the aquatic environment from a variety of sources. In order to remove phenolic compounds from water, a new natural sorbent, rice husk ash, was developed.
Materials and Methods: Removal of phenol, 2-chlorophenol and 4-chlorophenol were characterized by spectrophotometric technique at wavelengths of 269.5, 274 and 280 nm, respectively, under batch equilibrium conditions and via changing the parameters of contact time, initial pH, and initial concentration of adsorbates and dosages of sorbent. Finally, the results were analyzed by the kinetic and isotherm models.
Results: in this study, the equilibrium time was found to be 240 min for full equilibration of adsorbates. Removal percent of 2-chlorophenol was lower than two others. The maximum removal of phenol, 2-CP and 4-CP was observed at an initial pH of 5. The percentage removal of these phenolic compounds increased with increasing adsorbent dose and decreasing initial concentration. In kinetics studies, correlation coefficient and ARE factor showed that the sorption of phenol (R2=0.9999), 2-chlorophenol (R2=0.9992) and 4-chlorophenol (R2=1) fitted by pseudo second order model. Isotherm studies also revealed that, Langmuirmodel for phenol (R2=0.9499), Freundlich model for 2-chlorophenol (R2=0.9659) and 4-chlorophenol (R2=0.9542) were the best choices to describe the sorption behaviors.
Conclusion: Sorption process is highly dependent on the pH and it affects adsorbent surface characteristics, the degree of ionization and removal efficiency. At high pH hydroxide ions (OH-) compete for adsorption sites with phenol molecules. The sorption was done rapidly and a plateau  was reached indicating the sorption sites occuupied till  they were saturated. Since the increasing sorbent dose would improve sorption site, its increasing enhances phenolic compounds removal.

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Efficiency of powder activated carbon magnetized by Fe3O4 nanoparticles for amoxicillin removal from aqueous solutions: Equilibrium and kinetic studies of adsorption process
B Kakavandi, R Rezaei Kalantary, A Jonidi Jafari, A Esrafily, A Gholizadeh, A Azari,
Volume 7, Issue 1 (7-2014)
Abstract

Background and Objective: Extreme use of antibiotics and discharging them to the environment lead to serious consequences. Activated carbon is the most commonly adsorbent for these contaminants but its main drawback is difficulty of its separation. The objective of this study was synthesis of magnetic activated carbon by Fe3O4 and investigating its efficiency in adsorption of amoxicillin from synthetic wastewater. Materials and Methods: Materials and Methods: Physical and structural characteristics of the adsorbent synthesized were analyzed using SEM, TEM, XRD and BET techniques. The effect of factors like pH, initial concentration of amoxicillin and adsorbent, contact time, and temperature were investigated to determine thermodynamic parameters, equilibrium isotherms, and kinetics of adsorption process. Results: Physical characteristics of the magnetized activated carbon showed that Fe3O4 nanoparticles had the average size of 30-80 nm and BET surface area was 571 m2/g. The optimum conditions of adsorption were: pH=5, contact time=90min, adsorbent dose of 1g/L and temperature 200C. The equilibrium isotherms data showed that the adsorption process fitted both Freundlich and Longmuir models with the maximum capacity of 136.98 mg/g. The kinetic of the adsorption process followed pseudo second-order model. The negative values of &DeltaH0 and &DeltaG0 obtained from studying the adsorption thermodynamic suggested that amoxicillin adsorption on magnetic activated carbon was exothermic and spontaneous. Conclusion: The present study showed that the magnetic activated carbon has high potential for adsorption of amoxicillin, in addition to features like simple and rapid separation. Therefore, it can be used for adsorption and separation of such pollutants from aqueous solutions.


Algal treatment of a mixture of urban wastewater and Vinasse using Spirulina platensis microalgae
M Gholizadeh, M Nosrati,
Volume 12, Issue 3 (12-2019)
Abstract
Background and Objective: Algal wastewater treatment is a new and economic technology to remove and recycle nutrients from wastewater. In order to investigate the effect of vinasse on microalgae growth and also the effect of its growth on nitrogen and phosphate removal in a mixture of urban wastewater and vinasse, the growth of Spirulina platensis was studied.
Materials and Methods: Growth ability of spirulina in the urban wastewater and the effect of vinasse on growth rate was investigated by the calculation of biomass. The effect of concentration of vinasse, intensity of light and light-dark cycle on growth rate were studied by DESIGN EXPERT and CCD method. By selecting the optimized conditions, rates of nitrogen, phosphate and COD removal was investigated at the end of the growth period.
Results: The results showed that adding vinasse to wastewater increased the growth rate and the highest amount of biomass of 3.19 mg/mL was obtained in the sedimentary stream containing 0.25% vinasse. By evaluating the effect of vinasse concentration, intensity of light and light-dark cycle on growth rate, optimal conditions at vinasse concentration 0.4% (v/v), light intensity of 5000 lux and light period of 10 hours, 480 (mg/L) of biomass was obtained. The percentage of removal of nitrogen, phosphate and COD was 63%, 97% and 73% respectively.
Conclusion: The results of this study indicated the capability of urban wastewater and vinasse in order to replace Zarouk's culture medium for growth of Spirulina microalgae. These microalgae were able to remove high percentage of nutrients in the wastewater.
 

Evaluation of Gorganrood river water quality based on surface water quality indicators in Gonbad Kavous
Mohammad Gholizadeh, Omid Heydari,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: Increased untreated wastewater and unsustainable development of agriculture has deteriorated water quality of rivers. The aim of this study was to determine the quality of water in Gorganrud River basin using NSFWQI IRWQISC and Liou Pollution Index and compare them with the global standards. To do this, GIS software.was used
Materials and Methods: In this study, 5 sampling stations were selected based on standard criteria including land use type, accessibility and standard distributions along the river. 12 water quality parameters including dissolved oxygen, fecal coliform, pH, biochemical oxygen demand, chemical oxygen demand, temperature, organic phosphate, nitrate, ammonium, turbidity, total dissolved solids and electrical conductivity in river for one year were measured from June 2019 to May 2019 follwoing standard methods.
Results: The amount of phosphate and turbidity was increased along the river from station 2 to the mouth of the river. This was due to the presence of agricultural and municipal sewage. There was a significant difference in BOD, fecal coliforms and nitrates with those of the standard values. Water quality indicators showed the great effects of urban wastewater and human waste in the river area. The best quality was observed in Station 1 (75; Good Quality), which was less exposed to human activity and development. Based on the conformity of the results of the indicators with the terrestrial reality, the results of the IRWQIsc index (Iranian surface water quality) showed the best results due to compatibility to the land uses and the trend of variables.
Conclusion: The presence of urban sewage and unsustainable agricultural in the city of Gonbad Kavous is the most important reason for the decline in water quality (poor quality class). In this regard, a comprehensive management in water resources and environmental impact assessment is needed.

Investigating the efficiency of surface flow constructed wetlands by using Cyperus alternifolius plants for nitrate removal from water
Reza Nazarpoor, Masumeh Farasati, Abolhasan Fathaabadi, Mohamad Gholizadeh,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: Synthetic wetlands are engineering systems that use natural plants, soils and organisms to purify municipal polluted water and remove nitrate.
Materials and Methods: In this study, three systems were considerd as soil culture, three systems as plant cultivation on floating plates and three other systems without plant and porous bed as. The experiments were done three times within six months. The hydraulic retention times were 1, 3 and 5 days. The experimental design consisted of a factorial split-plot design. The analysis of variance showed that the efficiency of nitrate removal was affected by the type of constructed wetland, HRT, and temperature changes (p≤0.01).
Results: At the HRT of 1 day, the average efficiency of nitrate removal by the soil culture, plant cultivation on floating plates and control  were 14.34%, 12.09% and 10.51%, respectively. At the HRT of 3 days, the average efficiencies were 17.62%, 15.76% and 13.54%, respectively. At the HRT of 5 days, the efficiencies were increased and they were 17.75%, 17.66% and 16.08%, respectively.
Conclusion: The results showed that the soil culture were more efficinet in removing nitrate .Also, the Cyperus alternifolius plant has the potential of nitrate phytoremediation.

Hydrochemical assessment of Chehelchai river water, Golestan province for drinking and agricultural purposes
Mohammad Gholizadeh, Mohammad Zibaei,
Volume 13, Issue 2 (8-2020)
Abstract
Background and Objective: Surface water is usually highly variable in chemical composition due to contact with different geological formationsand other surface and groundwater resources.  Knowledge on water quality and the impact of human activities are particularly important for sustainable management and planning of water resources. The aim of this study was to investigate the physicochemical and hydrochemical quality of Chehelchai river water in Golestan province.
Materials and Methods: In this study, 6 sampling stations were selected based on standard criteria including land use type, accessibility and standard distributions along the river in 2018. 10 river water quality parameters including pH, electrical conductivity, total soluble solids, sulfate, chloride, bicarbonate, sodium, potassium, calcium and magnesium - were measured according to standard methods for one year period. Piper, Schuler, Durov, Wilcox and Gibbs diagrams were applied for hydrochemical analysis using RockWorks.17 software.  Statistical analysis was performed using one-way ANOVA.
Results:  Results indicated the abundance of major ions was found in the order of HCO3- > SO42- > Cl- and Ca2+ > Na+ > Mg2+ > K+. The river water type was predominantly determined as calcic bicarbonate. The findings revealed that the water of the study area is acceptable for drinking purpose based on Schuler diagram and also appropriate for agricultural uses considering Wilcox diagram (80% of the samples in class S1-C3 (saline - usable for agriculture)) and the average sodium uptake ratio (0.79).
Conclusion: The presence of dolomite ores, the absence of factories and domestic sewage and adhering to hygiene regulations by the residents, are the main reasons which have increased the quality of Chehelchai river water.

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