Ahmad Khosravi Baqdade; Taher Shahryari; Rasol Khosravi
Abstract
Background and purpose: Today, environmental pollution is a major problem for human life. Dye is one of the most important environment pollutants that is found in the industrial wastewater, especially in the textile industry wastewater. Therefore, the aim of this study was to evaluate the photocatalytic ...
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Background and purpose: Today, environmental pollution is a major problem for human life. Dye is one of the most important environment pollutants that is found in the industrial wastewater, especially in the textile industry wastewater. Therefore, the aim of this study was to evaluate the photocatalytic effect of green iron nanoparticles as catalyst for Reactive red 198 dye degradation in photocatalytic process. Materials and Methods: This study was performed laboratory using a batch reactor under UV A irradiation. In this study, the effect of different variables including pH (3-11), dye concentration (10-100 mg / l), catalyst dosage (0.25-3 g/l) and contact time (2-60 min) were investigated. The characterization of prepared nanoparticles were studied using different techniques such as TEM, FESEM and FTIR analysis. The obtained data were analyzed by Excel software. Results :Also, the photocatalytic tests showed high performance of NPs for dye degradation as catalyst in photocatalytic process. The highest removal efficiency achieved 96.2% at pH 3, catalyst dosage 1.5 g / L, contact time 15 min, and for dye concentration 25 mg / L. Conclusion :Additionally the results show that the photocatalytic process using green iron nanoparticles can be used with a suitable function to removal of reactive red 198 from aqueous solutions.
Maryam Hemmati; Arezoo Ghaemi; Haman Tavakkoli
Abstract
Introduction: Environmental problems caused by arrival of antibiotics in water resources due to toxicity and lasting effects are a serious threat. This study has been aimed to evaluate the efficiency of granular activated carbon as adsorbent for the removal of Cephalexin from aqueous solutions. Materials ...
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Introduction: Environmental problems caused by arrival of antibiotics in water resources due to toxicity and lasting effects are a serious threat. This study has been aimed to evaluate the efficiency of granular activated carbon as adsorbent for the removal of Cephalexin from aqueous solutions. Materials and Methods: This study was performed at laboratory scale and batch system. The influence of process variables such as pH of solution, adsorbent dosage, initial Cephalexin concentration and contact time were Investigated. Equilibrium study data were modeled using Langmuir, Freundlich and Temkin, moreover, kinetic studies were done by models of pseudo first order and pseudo second order. Findings: This research found that the Cephalexin adsorption efficiency decreased by increasing pH from 2 to 14, so that after 3 hours, the adsorption efficiency at the 20 mg.L-1 initial Cephalexin concentration and 0.2 g adsorbent, obtained 92.812%, 90.525% and 41.394% at pH 2, 3.5 and 14, respectively. The adsorption of Cephalexin was compatible with Langmuir isotherm and pseudo second order kinetic. Discussion and Conclusions: The present study showed that the granular activated carbon has high potential for adsorption and separation of Cephalexin and such pollutants from aqueous solutions, in addition to features like simple and rapid separation.
Mohsen Yazdani; Ali Asghar Najafpoor; Ali Akbar Dehghan; Hossein Alidadi; mahmood dankoob; Reyhane Zangi; Sima Nourbakhsh; Reza Ataei; Ali Asghar Navaei fezabady
Abstract
Background and objectives: Tetracycline is known as the second high consumed groups of antibiotics throughout the world, which their entrance into the domestic wastewater will lead to pollute the water resources. The aim of this study was to determine the performance of combined Ultrasonic/UVprocess ...
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Background and objectives: Tetracycline is known as the second high consumed groups of antibiotics throughout the world, which their entrance into the domestic wastewater will lead to pollute the water resources. The aim of this study was to determine the performance of combined Ultrasonic/UVprocess in removal of tetracycline antibiotic from aqueous environments. Material and methods: This experimental study was performed by the ultrasonic bath associated with ultraviolet radiation. To determine the effects of independent variables including contact time (5-60 min), initial antibiotic concentration (5-25 mg/l), pH (3-10) and the input power (100- 300 W) on response variable (tetracycline removal), the samples were taken from reactor in different time intervals and the residual concentrations of tetracycline were measured by spectrophotometer in 261 nm wavelength. Results: The results of this study showed that the removal efficiency of UV and Ultrasonic processes was16% and 32% in optimum conditions, respectively. While in Ultrasonic /UV process, removal efficiency increased. The best removal efficiency (72%) was observed in pHof 4.5, antibiotic concentrationof10 mg/I, input power of240 W and contact timeof50 min. Conclusion: According to the obtained results, Ultrasonic/UVprocess can be used as an effective process to remove the tetracycline antibiotic from aqueous solutions.
hosein alidadi; maryam dolatabadi; marjan mehrabpour
Abstract
Background and Objectives: Nitrate contamination of surface and groundwater is considered as one of the more serious problems in throughout the world. High nitrate concentration in water (higher than standards) is very dangerous, consuming such polluted water can lead to Methemoglobinemia disease ...
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Background and Objectives: Nitrate contamination of surface and groundwater is considered as one of the more serious problems in throughout the world. High nitrate concentration in water (higher than standards) is very dangerous, consuming such polluted water can lead to Methemoglobinemia disease in children and the formation of the carcinogenic nitrosamines in adults. . The aim of this study was to investigate the possibility using of Modified clinoptilolite Zeolite by Cationic Surfactants adsorbent in nitrate removal from aqueous solutions. Materials and Methods: In this empirical study, the effects of different independent variables including adsorbent dose (1-3 g/l), initial concentration of nitrate (50-150 mg/l), pH (4-10) and contact time (15-120 min) on elimination of nitrate was investigated. Also, adsorption kinetic along with Langmuir and Freundlich isotherms was studied. Results: The obtained results showed that the maximum removal efficiency of NO3 was in the initial nitrate concentration of 50 mg/L, pH of 4, adsorbent dose of 3 g/l, and contact time of 90 min. Also, the results indicate that the nitrate adsorption by modified Clinoptilolite zeolite was fitted well with Freundlich isotherm (R2=0.9951), and second- order kinetics (R2=0.9998). Conclusion: According to the attained results, the Clinoptilolite zeolite can be considered as an appropriate and economical adsorbent for elimination of nitrate from aqueous solutions. Concerning its simple modification method and low cost, it can be applied as an adsorbent for other anionic pollutions. .
Amin Ahmaditabar; Mohammad Hadi Dehghani; Faezeh Izadpanah
Abstract
Background & Objective: Textile effluents contain significant amounts of toxic and organic pollutants. Due to health risks such as carcinogenic and mutagenic effects, discharge of this kind wastewater to water resources can lead to health impacts. The aim of this study was to survey the efficiency ...
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Background & Objective: Textile effluents contain significant amounts of toxic and organic pollutants. Due to health risks such as carcinogenic and mutagenic effects, discharge of this kind wastewater to water resources can lead to health impacts. The aim of this study was to survey the efficiency of Chitosan derivative in removal of basic dyes violet16 from aqueous solutions. Materials & Methods: In this study the influence of different parameters including contact time, initial dye concentration, adsorbent concentration, and PH, was studied. Residual of dye concentration was measured using a spectrophotometer set in 545 nm wavelength. Adsorption data was described by Langmuir and Freundlich isotherms and kinetic reactions. Results: The results showed that increasing contact time and adsorbent dose enhances dye removal rates for this adsorbent. By decreasing initial concentration of dye, removal rates increased. In optimal conditions, Chitosan derivatives were able to remove dye 68 percent respectively. For this adsorbents optimum pH was obtained 10. According to the results, adsorption process for both adsorbents was determined by Freundlich isotherm by R2>0.98. Dye absorption kinetic of both adsorbents followed pseudo second degree by R2>0.98. Conclusion: the results showed that Chitosan derivative can be applied as an efficient adsorbent for removal basic violet 16 dye from aqueous solutions.