Zahra Mohebi; Maryam Nazari
Abstract
Disposal of waste products and residuals into the natural water bodies can havefatal consequences for aquatic ecosystems, posing severe threats to naturalhabitats and human health. Natural treatment systems are the most suitabletreatment technologies for various types of wastewaters, which has attracted ...
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Disposal of waste products and residuals into the natural water bodies can havefatal consequences for aquatic ecosystems, posing severe threats to naturalhabitats and human health. Natural treatment systems are the most suitabletreatment technologies for various types of wastewaters, which has attracted muchattention in recent years. Phytoremediation is a plant-based technique used toeliminate or recover surplus nutrients in contaminated environments. The use ofaquatic plants in wastewater phytoremediation is very efficient due to they have avery significant ability for assimilating and degrading contaminants (e.g., nitrates,phosphates, and heavy metals). Phytoremediation is a relatively new technologythat is considered as an operational, efficient, new, and environmentally friendlytechnology that is still in the early stages of development and optimization. Itsapplication on a large scale is still limited. It should also be noted that a clear visionof this innovation should be taken into account and, accurate data should be madeavailable to the public as it will enhance its efficiency as a manageable solution inthe worldwide. Additionally, phytoremediation has been evaluated as a separatelow-tech and environmentally friendly green option compared to the existingtechnologies. The present study attempts to review the recently published literatureto explain phytoremediation technology and its advantages in purifying water andwastewater.
Simin Shokrolahi; Mehrdad Farhadian; Nila Davari
Abstract
ZnO/Fe2O3/Zeolite nanophotocatalyst was synthesized by sol-gel method, and its performance in degradation of ENR, as one of the most commonly used veterinary antibiotics, is evaluated. The synthesized nanophotocatalyst is characterized by XRD, XRF, FT-IR, FE-SEM, EDX, and BET analyses. According to XRD, ...
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ZnO/Fe2O3/Zeolite nanophotocatalyst was synthesized by sol-gel method, and its performance in degradation of ENR, as one of the most commonly used veterinary antibiotics, is evaluated. The synthesized nanophotocatalyst is characterized by XRD, XRF, FT-IR, FE-SEM, EDX, and BET analyses. According to XRD, FT-IR, and EDX, presence of ZnO and Fe2O3 on the zeolite surface is confirmed. Based on XRF results, the optimal molar value of Fe3+/ZnO in the synthesized nanophotocatalyst is obtained as 0.06. The FE-SEM results confirm the deposition of ZnO/Fe2O3 on the zeolite surface and indicate the approximate size of the photocatalyst particles as 48 nm. According to BET results, the specific surface area and pore volume for the synthesized nanophotocatalyst are obtained as 280.16 m2/g and 0.35 cm3/g, respectively. The simultaneous effects of operational factors, including the concentration of pollutant (150-450 mg/l), initial pH of the solution (5-9), and H2O2 concentration (50-200 mg/L) are examined on the ENR degradation efficiency via RSM. The results demonstrate that ENR concentration, pH, and H2O2 concentration have significant impacts on the ENR degradation efficiency in turn. According to the experimental results under optimal conditions (pH, contaminant concentration, and H2O2 concentration: 9, 500 mg/l, and 90 mg/l, respectively), the ENR degradation efficiency is 97.4%. This study suggests that the synthesized nanophotocatalyst has an acceptable efficiency to degrade a non-biodegradable contaminant.
Peyman Mahmoodi; Mehrdad Farhadian; Ali Reza Solaimany Nazar; Amin Noroozi
Volume 1, Issue 1 , March 2014, , Pages 18-22
Abstract
The efficiency of diazinon (as insecticides) and nitrate (related to nitrogen fertilizer) removal from contaminated water is investigated through NF membrane technique. The effects of nitrate concentration (40-160 mg/l), diazinon concentration (10-1000 µg/l) and pH (5-9) on the efficiency of a ...
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The efficiency of diazinon (as insecticides) and nitrate (related to nitrogen fertilizer) removal from contaminated water is investigated through NF membrane technique. The effects of nitrate concentration (40-160 mg/l), diazinon concentration (10-1000 µg/l) and pH (5-9) on the efficiency of a commercial polyamide nanofilter membrane at a constant pressure of (800 KPa) are investigated. The response surface method (Box-Behenken design) is applied in design of experiment. As the diazinon concentration and pH are enhanced, the contaminant removal efficiency increases from 85% to 90%; while nitrate concentration has an opposite effect (removal efficiency reduces about 10%). The regression models obtained for nitrate and diazinon rejection show good fitting to the experimental results (r-squared equal to 94% and 98%, respectively). The models are able to predict the evolution of diazinon and nitrate as a function of concentration and pH at a constant pressure.
