Health and environment
atefeh dehnabi; ahmad Allahabadi; MohammadHossein Saghi; Forough Riahimanesh
Volume 29, Issue 4 , September and October 2022, , Pages 531-548
Abstract
Introduction: Today, heavy metals and organic compounds such as dyes are among the most dangerous pollutants that have entered surface and groundwater and threaten human health. The aim of this study was to investigate the removal of reactive orange 3R dye and chromium by adsorption separately and simultaneously ...
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Introduction: Today, heavy metals and organic compounds such as dyes are among the most dangerous pollutants that have entered surface and groundwater and threaten human health. The aim of this study was to investigate the removal of reactive orange 3R dye and chromium by adsorption separately and simultaneously activated carbon.
Materials and Methods: In this study, Sycamore carbon modified with NH4Cl was used to remove contaminants. Effect of variables such as pH (2-9), adsorbent concentration (0.5-1-0 g/L), pollutant concentration (10-50 mg/L) and contact time (2-40 minutes) on dye and chromium removal (simultaneously and separately) were calculated. Freundlich and Langmuir adsorption isotherm models and kinetics were also investigated.
Results: The results of this study showed that activated carbon at pH = 4, 0.4 g/L adsorbent at 15 min contact time has the best removal conditions for both paint and chromium contaminants. Under optimal conditions, activated carbon was able to remove 72% of chromium and 84% of dye separately and 59% of chromium and 67% of dye simultaneously in solution at a concentration of 25 mg/L. The study of adsorption isotherms also showed that the experiments were more consistent with the Freundlich model.The absorption kinetics follows Pseudo-second order equations.
Conclusion: According to the results, this adsorbent has a good performance in separate and simultaneous removal of paint and chromium and can be used to treat wastewater containing organic and inorganic contaminants.
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 ...
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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
Health and environment
Ali Esrafili; Maryam Izanloo; Mahdi Farzadkia; Ahmad Joneidi Jafari; Mina Yousefi
Volume 26, Issue 4 , November and December 2019, , Pages 535-546
Abstract
Nowadays,due to the irreparable effects imposed on aquatic ecosystems,organisms and humans,the removal of heavy metals and herbicides from water sources has extremely become vital.In recent years, the process of adsorbing contaminants with magnetic nanoparticles has gained lots of attention.Therefore, ...
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Nowadays,due to the irreparable effects imposed on aquatic ecosystems,organisms and humans,the removal of heavy metals and herbicides from water sources has extremely become vital.In recent years, the process of adsorbing contaminants with magnetic nanoparticles has gained lots of attention.Therefore, the present study aimed to synthesize nanoparticles as an adsorbent for adsorption of the contaminants of Pb and 2,4-D from water. Materials and methods:To evaluate the effect of independent variables such as pH(3-11),contact time(0-150min),adsorbent dose(0.2-1.2g/L) and adsorbate concentration(5-50mg/L) on the contaminant removal and determine the optimal conditions, the method of one factor at the time was used by design expert software. Nanoparticles were synthesized via a co-precipitation method and their morphology were characterized by TEM,XRD,FT-IR and SEM. Finally, the experiments were performed on aqueous solution. Results: Structural analysis revealed that adsorbent has a spherical structure with a Fe3O4 core and SiO2 shell, modified by both amine and thiol functional groups.The results of experiments showed that the maximum adsorption efficiency of single system occurred at pH 5 and contact time 40 min for lead and at pH6 and contact time 90min for 2,4-D.Also the optimal values of adsorbent dose and initial concentration obtained 0.8 g/L and 10 mg/L. In the binary adsorption system,the maximum adsorption efficiency determined at pH 6 and contact time 40 min for lead and contact time 60 min for 2,4-D and adsorbent dose 1.2 g/L. Conclusion:According to the results,the bi-functional nanoadsorbent could be effectively used for the simultaneous removal of inorganic and organic pollutants from various aqueous solutions.
Mahnaz tora bi hokmabadi; Ahmad Allahabadi; Gholamreza Moussavi
Volume 26, Issue 3 , September and October 2019, , Pages 273-283
Abstract
Herbicides, including atrazine, are among the most important newly discovered contaminants found in water bodies and are hazardous to human health and the environment. adsorption is one of the best techniques used to remove these contaminants from contaminated water. Materials and method: In this ...
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Herbicides, including atrazine, are among the most important newly discovered contaminants found in water bodies and are hazardous to human health and the environment. adsorption is one of the best techniques used to remove these contaminants from contaminated water. Materials and method: In this study, two carbon from waste Pomegranate and calligonum Comosum were used to remove atrazine herbicide. After chemical activation these carbons with NH4Cl, and then 800 ° C for 2 hours, parametric tests were performed and the effect of pH, adsorbent concentration, atrazine concentration and contact time were investigated; then absorption equilibrium tests; absorption capacity and its isotherms investigated for the removal of atrazine by two carbons were calculated. Results: The results showed that the carbon produced from the calligonum Comosum wood in optimal conditions at pH =7; carbon concentration 0.2 g/L, and the mixing time of 50 minutes could remove 100% atrazine at 25 mg/L . The carbon produced from pomegranate in optimal conditions pH =6; carbon concentration of 0.2 g/L and mixing time of 50 minutes could remove 91.5% atrazine to 25 mg/ L. Absorption equilibrium tests showed that the absorption capacity of carbon Calligonum Comosum and pomegranate were 672 and 645mg/g respectively. Discussion The results of this study showed that both carbons have high absorption capacity in the removal of atrazine herbicide and can be an effective and economical absorbent for the removal of this contaminant from natural waters.
Health and environment
Ahmad Alahabadi; Abolfazl Rahmani Sani; Zahra Rezai; Mahnaz Torabi
Volume 25, Issue 4 , September and October 2018, , Pages 528-536
Abstract
Background and Background and goal : The attendance of humic acid in water resources is the main health problems of many Societies. There are various methods for decreasing or removing of humic acid. Of these absorbed is considered an effective method to remove it. SO Agriculture wastes were used for ...
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Background and Background and goal : The attendance of humic acid in water resources is the main health problems of many Societies. There are various methods for decreasing or removing of humic acid. Of these absorbed is considered an effective method to remove it. SO Agriculture wastes were used for preparation of activated carbons by chemical activation using Ammonium chloride.Method: In this study, the standard Merck carbon and carbon produced from plant waste used as adsorbents and adsorption experiments were performed in batc. Adsorption of humic acid (HA) on SAC and NAC as a function of solution initial pH (2-10), adsorbent dosage (0.1-1 g/L), contact time (5-50 min), concentration (5-20 mg/L), on the adsorption capacity, the two-parameter equilibrium models (Langmuir and Freundlich equations) were debated. Result: The result showed that the pH effect at removal humic acid is an important parameter, and isotherm showed that the adsorption Followed of the Langmuir isotherm. Also it was found that the capacity of absorb can be markedly effected by carbon type. That it was 238, 294 , 250 mg/g For carbons Merck, Sycamore and steel respectively.Conclusion: Carbon prepared from Steel due to very high capacity could be effective for removal humic acid from aqueous solution.
Mansur Zarrabi; Mohammad Noori Sepehr; Mohammad Shakak; Gholamreza Ebrahimzadeh; Mahmoud Taghavi
Volume 24, Issue 4 , July and August 2017, , Pages 239-248
Abstract
Background & Objectives: Phosphorus is a common ion in wastewater treatment effluents, but excess amount of phosphate concentration in the effluent discharge accelerates eutrophication that affects many natural water bodies. Eutrophication of the water bodies is one of the most important environmental ...
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Background & Objectives: Phosphorus is a common ion in wastewater treatment effluents, but excess amount of phosphate concentration in the effluent discharge accelerates eutrophication that affects many natural water bodies. Eutrophication of the water bodies is one of the most important environmental problems. Eutrophication can lead to abundant development of aquatic plants, growth of algae and disturbance to the balance of organisms present in the water. Therefore, in present work, natural and modified yellow and red soil with EDTA was used for removal of phosphorous from aqueous solution.
Materials & Methods: All experiments were conducted in a batch system. Natural yellow and red soil and its modified one with EDTA were used as adsorbent for removal of phosphorous from aqueous solutions. Effect of various experimental parameters such as pH, initial phosphorus concentration, contact time and adsorbent mass were investigated.
Results: Results showed that the removal efficiency was increased by increasing in contact time, adsorbent mass and initial phosphorus concentration. Higher removal efficiency was observed at 150 min contact time, 10 g/L adsorbent mass, 50 mg/L phosphorus concentration and pH 5. At these conditions, about 65% of phosphorus were removed by natural soils, while 78% was removed by modified adsorbents.
Conclusion: The results of present work well demonstrate that, due to higher content of calcium, red and yellow soil is capable for adsorption of phosphorus and if they be modified with EDTA, their efficiency will be improved remarkably.
Sahand Jorfi; Nematallah Jafarzadeh Haghighifard; Mohammad Javad Ahmadi; Narjes Shaheidar; Hakimeh Purhoseini
Volume 24, Issue 1 , March and April 2017, , Pages 55-62
Abstract
Background & Objectives: Cr(IV) is a toxic heavy metal with dangerous effects on health and environment and is discharged through industrial effluents. The main aim of the current study was to determine the efficiency of natural zeolite on removal Cr(IV) from aqueous solutions. Materials & Methods: ...
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Background & Objectives: Cr(IV) is a toxic heavy metal with dangerous effects on health and environment and is discharged through industrial effluents. The main aim of the current study was to determine the efficiency of natural zeolite on removal Cr(IV) from aqueous solutions. Materials & Methods: Following the chemical modification of Zeolite, the study variables including pH (2-10), adsorbent dosage (2-20 g/L), reaction time (5-150 min) and Cr(IV) concentration (10-50) were optimized according to the one at the time experimental design. The correlation of obtained data with conventional isotherms and kinetics were also studied. Results: In optimum pH 2, reaction time of 30 min and adsorbent dosages of 8 g/L, the most removal efficiency of 99.53% was observed for initial Cr(IV) concentration of 10 mg/L. The Freundlich isotherm and pseudo –second order kinetics were better fitted to the findings. Conclusions:According to findings of current study in lab scale, it can be concluded that natural Zeoliite can be considered as an efficient and cost effective alternative on treatment of effluents containing Cr(IV).
Zahra Rezaei Gozal Abad; Ahmad Alah Abadi; Ahmad Hosseini-Bandegharaei; Ayoob Rastegar; Farzad Mohammadi; Shahram Nazari
Volume 23, Issue 4 , September and October 2016, , Pages 608-617
Abstract
Objectives Phenol is known as a toxic and carcinogen compound in the environment. It also produces unpleasant taste and odor in water reservoirs. In this study, the efficiencies of modified and conventional rice husk ashes as low-cost adsorbents were compared regarding phenol removal from aqueous solutions. ...
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Objectives Phenol is known as a toxic and carcinogen compound in the environment. It also produces unpleasant taste and odor in water reservoirs. In this study, the efficiencies of modified and conventional rice husk ashes as low-cost adsorbents were compared regarding phenol removal from aqueous solutions. Methods This study is an interventional laboratory research in which, at first carbonized rice husk was prepared at a temperature of 450°C. Then, to improve rice husk ash adsorption capacity, NH4CL was used for its modification. Then, the effects of physiochemical factors (pH, contact time, phenol concentration and adsorbent dose) on phenol removal were studied. Results Findings showed that the phenol removal by modified and conventional rice husk ash was 94.85% and 52.8%, respectively. The adsorption process for both adsorbents followed Freundlich isotherm (R2≥ 0. 99) and the pseudo-second order model (R2>0.99). Maximum adsorption capacity based on Langmuir model for the modified and conventional husk rice ashes were 66.6 mg/g and 4.7 mg/g, respectively. Conclusion Results indicated that efficiency of modified husk rice ash was more than that of the conventional type in phenol removal, causing less adsorbent consuming in the industrial treatment plants. Therefore, because of its availability and easy modification, it can be used in water and wastewater technology for phenol removal.
Mehdi Baghayeri; Behrooz Maleki; Ahmad Alahabadi; Forough Reyahi Manesh; Amirhassan Amiri
Volume 23, Issue 3 , July and August 2016, , Pages 458-467
Abstract
Backround Pharmaceutical resources are becoming increasingly problematic contaminants of water resources, particularly in surface and groundwater sources located around industrial and residential communities. They enter water sources mostly through discharges from pharmaceutical industries and municipal ...
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Backround Pharmaceutical resources are becoming increasingly problematic contaminants of water resources, particularly in surface and groundwater sources located around industrial and residential communities. They enter water sources mostly through discharges from pharmaceutical industries and municipal wastewater. Consumption of water contaminated with pharmaceutical discharges can have several harmful effects like acute and chronic toxicity in humans. Another critical concern regarding pharmaceutical discharges in water sources is the development of bacterial resistance to medicinal treatment of bacterial infections.Materials & Methods The activated carbon was purchased from Merck Co. A stock solution of 1000 mg/L of entacapone was prepared by dissolving 1.0 g entacapone in 1 L distilled water. In this study, two types of contaminated water (aqueous solution and contaminated real water) were prepared and examined. The aqueous solution was made from mixing aliquots of entacapone stock solution with distilled water. To determine the remaining entacapone in the samples, they were analyzed by a Hach UV-VIS spectrophotometer (DR5000).Results This study showed that activated carbon could be functionalized with magnetic nanoparticles and such magnetic-activated carbon could be used as adsorbents for the removal of entacapone from water samples. The results showed that contact time, sample pH, concentration of entacapone, and concentration of the adsorbent were effective on the removal process. The equilibrium results showed the best fit with Langmuir model with a maximum adsorption capacity of 357.1 mg/g.Conclusion We described here the preparation of magnetic-activated carbons in one reaction step, and the prepared carbon was used as the adsorbents to remove entacapone from water samples rapidly and effectively. The magnetic nanoparticles can be well immobilized on activated carbons and easily separated from the solution using an external magnet. The results revealed that magnetic-activated carbons could be used as the potential adsorbents for removing entacapone from environmental water.
Abdolkazem Neisi; Mehdi Vosoughi; Anvar Asadi; Mohammad Javad Mohammadi; Mohammad Shirmardi; Mehdi Fazlzadeh; Amir Zahedi
Volume 23, Issue 3 , July and August 2016, , Pages 478-489
Abstract
Background Many industries can pollute water quality due to their wastewater discharging into water resources. Textile industries are one of the main sources of water pollution. Due to their high toxicity, wastewaters containing dyes cause many environmental problems. Acidic dyes are one of the main ...
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Background Many industries can pollute water quality due to their wastewater discharging into water resources. Textile industries are one of the main sources of water pollution. Due to their high toxicity, wastewaters containing dyes cause many environmental problems. Acidic dyes are one of the main classes of dyes. In this study, nano-alumina and micro-alumina powder have been used for the adsorption of acid red 14 dye.Materials & Methods This study was carried out in the batch system in laboratory scale. Different parameters such as initial dye concentration, pH, and adsorbent dose were examined. Spectrophotometry (UV/VIS Lambda 25 Perkin Elmer, Shelton) was used to quantify the remaining dyes concentration. Adsorption isotherm and kinetic behaviors of adsorbent for acidic dye removal were studied and fitted to different models.Results The result showed that with increasing the contact time, acid red 14 removal efficiency by micro-alumina and nano-alumina powder and amount of adsorption per mass unit (qe) increased to 18 and 40 mg/L, respectively, and when adsorbent dose increased from 0.2 to 1.2 g/L, qe decreased from 23 to 12 and 47 to 39, respectively. With increasing the pH value in examined range, the removal efficiency decreased from 30 to 6 and 60 to 15 for micro-alumina and nano-alumina powder, respectively. The results of the study of adsorption of acid red 14 by micro-alumina and nano-alumina powder revealed that its kinetics obeyed pseudo-second order (R2>0.99 and 0.98, respectively). The results of present study on adsorption of acid red 14 on micro-alumina and nano-alumina powder revealed that isotherm obeyed Langmuir adsorption (R2 >0.99 and 0.98, respectively). Conclusion The present study showed that the nano-alumina rather than mciro-alumina can be a promising adsorbent for the removal of acidic dyes such as acid red 14.
Mahnaz Torabi-Hokmabadi; Ahamd Alahabadi; Abolfazl Rahmani-Sani; Somayyeh Zarei-Tazarghi; Hamidreza Karimi-Sani; Mohamadreza Behrozikhah
Volume 23, Issue 3 , July and August 2016, , Pages 504-515
Abstract
Background Painkillers such as diclofenac are widely used in human medicine and veterinary medicine. Because of their excretion into water resources and subsequent environmental hazards, their removal from the waters and wastewaters is essential. Since, these drugs cannot undergo biodegradation, an advanced ...
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Background Painkillers such as diclofenac are widely used in human medicine and veterinary medicine. Because of their excretion into water resources and subsequent environmental hazards, their removal from the waters and wastewaters is essential. Since, these drugs cannot undergo biodegradation, an advanced treatment such as adsorption method must be applied for their removal and one of the best adsorbents in this regard is activated carbon. This study aimed to investigate the removal of diclofenac contaminant by NH4Cl-induced activated carbon.Materials & Methods Activated carbon produced from agricultural wastes was impregnated with ammonium chloride (NH4Cl) and activated at 800°C. The experiments were conducted in a closed system using a magnet stirrer at 100 rpm. In this investigation, the effects of several variables, namely adsorbent concentration, contact time, pH, and temperature, on the removal of diclofenac were evaluated. Then, isotherms and adsorption thermodynamic were explored. We used DR 5000 spectrophotometer model for drug analysis with the wavelength of 275 nm.Results The produced NAC (NH4Cl-induced activated carbon), having the special surface of 1029 m2/g and pores volume of 2.46 nm, was able to remove 0.81% of diclofenac from a solution of 50 mg/L at the sorbent concentration of 0.8 mg/L, pH 6, in 20 minutes time. The equilibrium adsorption experiments showed that the absorption of diclofenac on NAC followed the Longmuir model and the absorption capacity was 212.5 mg/g. Using the diclofenac concentration of 50 mg/L and other optimal conditions, thermodynamic studies of diclofenac absorption on NAC showed that the amount of drug removal increased from 73% to 95% with increasing temperature from 10°C to 40°C. Conclusion NAC can be used as a convenient and inexpensive adsorbent for the removal of diclofenac and other drug compounds from polluted waters and wastewaters.
Mohammad Malakotian; Ali Asadipour; Somayyeh Mohammadi Senjedkooh
Volume 23, Issue 1 , May and June 2016, , Pages 110-121
Abstract
Background & Objectives: Textile industry is one of the largest industries producing dying wastewater. Discharge of this wastewater to acceptor waters endangers aquaticslife through reducing light transmission, reducing dissolve oxygen, and increasing COD. This study investigated the efficiency of ...
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Background & Objectives: Textile industry is one of the largest industries producing dying wastewater. Discharge of this wastewater to acceptor waters endangers aquaticslife through reducing light transmission, reducing dissolve oxygen, and increasing COD. This study investigated the efficiency of calcium peroxide nanoparticles in removal of Reactive Red 198 from synthetic wastewater and wastewater of YAZDBAF textile factory. Materials & Methods: This experimental study was performed in spring and summer of 2014 in Environmental Health Engineering Research Center of Kerman University of Medical Science. Characteristic of synthesized nanoparticles was determined by TEM and XRD. Adsorption experiments in batch system were performed on synthetic sample and real wastewater. The effect of solution pH (3-13), initial concentration of dye (10-300 mg/L), contact time (5-90 min) and adsorbent dosage (0.05-0.6 g) was investigated and adsorption isotherms were determined. Data was analyzed by SPSS version 21, Excel 2007 softwares and Pearson correlation coefficient. Results: Synthesized adsorbent particles had uniformly spherical shape with approximately diameter of 15-25 nm. The optimum pH for removal of reactive red 198 was 3-7. The equilibrium contact time was 50 minutes and optimum dosage of adsorbent was 0.4 g/100 mL. In these optimum conditions, removal efficiency in synthetic and real sample was 99.58 and 76.18 percent, respectively. Conclusion: Based on the results, calcium peroxide is an efficient adsorbent in removing reactive red 198 and, with attention to simplicity of synthesis, it can be used as an applied in treating textile wastewaters.
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 ...
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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.
Ayyob Rastegar; Zahra Rezaee Gezal Abad; Ahmad Allahabadi; Abolfazl Rahmani Sani; RamezanAli Khamirchi
Volume 21, Issue 6 , January and February 2015, , Pages 1090-1102
Abstract
Background: Aniline is an important chemical compound which has wide applications in several industries such as dyestuffs, rubbers, pesticides and plastics. It is highly toxic and has injurious influences on human physical conditions and aquatic life. Therefore the purpose of this study is to investigate ...
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Background: Aniline is an important chemical compound which has wide applications in several industries such as dyestuffs, rubbers, pesticides and plastics. It is highly toxic and has injurious influences on human physical conditions and aquatic life. Therefore the purpose of this study is to investigate the effects of NH4Cl-induced activated carbon (NAC) and standard activated carbon (SAC) in aniline removal from aqueous solutions were investigated. Material & method: This study is of experimental–intervention type. An UV-Visible spectrophotometer (CECIL CE7400) used For determination of remaining aniline concentrations. The effect of various parameters like adsorbent dose, pH, contact time and initial aniline concentration were studied for optimization.
Results: The results showed that the prepared NAC had a higher absorption capacity than standard activated one. The maximum adsorption capacity of aniline onto SAC and NAC was 1666 and 1000 mg/g, respectively, and the rate removal was dependended to pH, contact time, aniline concentration and absorption type. Results of equilibrium experiments indicated that the adsorption process of aniline onto SAC and NAC follows Langmuir model (R 2> 0.99.47 and 0.99,776 ). Also, kinetics of adsorption process follows pseudo second-order model with correlation R2> 0.99.97 and 0.99,30 respectively for SAC and NAC.
Conclusion: These consequences show that the developed NAC was a more competent adsorbent than SAS for removal aniline in water.
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 ...
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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.
Ferdovs Kord MostafaPor; Edris Bazrafshan; Farnaz Heidar Nejad
Volume 20, Issue 2 , May and June 2013, , Pages 142-153
Abstract
Background: Phenol is one of the main components concerned in the industrial wastewater. Physicochemical or conventional biological methods are usually used for the treatment of wastewater with high concentrations of phenol. At present study, the adsorption potential of phenol from aqueous solutions ...
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Background: Phenol is one of the main components concerned in the industrial wastewater. Physicochemical or conventional biological methods are usually used for the treatment of wastewater with high concentrations of phenol. At present study, the adsorption potential of phenol from aqueous solutions by Pistachio hull ash was investigated.
Materials and methods: Present study is an experimental survey that was performed in a batch system. To study the efficiency of Pistachio hull ash in phenol removal from aqueous solutions, the effect of critical variables such as contact time (15, 30, 45, 60, 75, 90, 105 and 120 min), initial phenol concentration (5, 10, 20, 30, 40, 50 and 100 mg/L), adsorbent dosage (0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 g/L) and initial pH of solution (2,3,4,5,6,7,8,9,10,11,12,13) was investigated.
Results: Maximum adsorption capacity of the Pistachio hull ash was 327.6 mg/g at pH 5, initial concentration of 100 mg/L and reaction time 45 min, which 98.28% of the phenol was removed. The adsorption equilibriums were analyzed by Langmuir and Freundlich isotherm models. It was found that the data fitted to Freundlich (R2=0.9436) better than Langmuir (R2=0.8395) model.
Conclusion: According to achieved results, it was observed that Pistachio hull not only was an inexpensive absorbent, but also a quite effective factor in removal of phenol from water and wastewater.