@article { author = {Serag, Eman and El Nemr, Ahmed and El-Maghraby, Azza}, title = {Synthesis of Highly Effective Novel Graphene Oxide-Polyethylene Glycol-Polyvinyl Alcohol Nanocomposite Hydrogel For Copper Removal}, journal = {Journal of Water and Environmental Nanotechnology}, volume = {2}, number = {4}, pages = {223-234}, year = {2017}, publisher = {Iranian Environmental Mutagen Society}, issn = {2476-7204}, eissn = {2476-6615}, doi = {10.22090/jwent.2017.04.001}, abstract = {A novel Graphene oxide-polyethylene glycol and polyvinyl alcohol (GO-PEG-PVA) triple network hydrogel were prepared to remove Copper(II) ion from its aqueous solution. The structures, morphologies, and properties of graphene oxide (GO), the composite GO-PEG-PVA and PEG-PVA were characterized using FTIR, X-ray diffraction, Scanning Electronic Microscope and Thermal Gravimetric analysis. A series of systematic batch adsorption experiments were conducted to study the adsorption property of GO, GO-PEG-PVA hydrogel and PEG-PVA hydrogel under different conditions (e.g. pH, contact time and Cu2+ ions concentration). The high adsorption capacity, easy regeneration, and effective adsorption–desorption results proved that the prepared GO-PEG-PVA composite hydrogel could be an effective adsorbent in removing Cu2+ ion from its aqueous solution. The maximum adsorption capacities were found to be 917, 900 and 423 mg g–1 for GO-PEG-PVA hydrogel, GO and PEG-PVA hydrogel, respectively at pH 5, 25 °C and Cu2+ ions’ concentration 500 mg l–1. The removal efficiency of the recycled GO-PEG-PVA hydrogel were 83, 81, 80 and 79% for the first four times, which proved efficient reusability.}, keywords = {copper,Graphene oxide,Hydrogel,Polyethylene glycol,Polyvinyl alcohol}, url = {https://www.jwent.net/article_28430.html}, eprint = {https://www.jwent.net/article_28430_d0963ae5eae3179383d1bcff1a7a6a61.pdf} } @article { author = {Yousefi, Mohammad Hadi and Zerafat, Mohamad Mehdi and Shokri Doodeji, Majid and Sabbaghi, Samad}, title = {Investigation of Dip-Coating Parameters Effect on The Performance of Alumina-Polydimethylsiloxane Nanofiltration Membranes for Desalination}, journal = {Journal of Water and Environmental Nanotechnology}, volume = {2}, number = {4}, pages = {235-242}, year = {2017}, publisher = {Iranian Environmental Mutagen Society}, issn = {2476-7204}, eissn = {2476-6615}, doi = {10.22090/jwent.2017.04.002}, abstract = {The objective of this work is to investigate the effect of dip-coating parameters on the performance of Alumina-PDMS hybrid nanofiltration membranes for water desalination. Ceramic supports used in this work were prepared with a 340 nm average pore size and 34% total porosity. The aim is to determine optimum conditions of dipping time, PDMS concentration, and withdrawal speed in order to achieve high rejection and flux values. Dip-coating parameters were considered as dipping time (60 - 120 s), withdrawal speed (5 - 15 mm/s) and PDMS concentration (10 - 20 wt. %). Hybrid membranes were characterized using FE-SEM and FTIR analysis techniques. Pure water flux and salt rejection were also measured to evaluate the rejection performance. Alumina-PDMS hybrid nanofiltration membranes fabricated with dipping time = 120 s, withdrawal speed = 15 mm/s and 10 wt. % PDMS exhibited the best performance giving 30.5% rejection for NaCl and 53.8% for Na2SO4.  }, keywords = {Alumina,Dip-Coating,Hybrid Membranes,Nanofiltration,PDMS}, url = {https://www.jwent.net/article_28431.html}, eprint = {https://www.jwent.net/article_28431_00e4df3074fecaf88420bc3353f8fc9b.pdf} } @article { author = {Jafarinejad, Shahryar}, title = {A Comprehensive Study on the Application of Reverse Osmosis (RO) Technology for the Petroleum Industry Wastewater Treatment}, journal = {Journal of Water and Environmental Nanotechnology}, volume = {2}, number = {4}, pages = {243-264}, year = {2017}, publisher = {Iranian Environmental Mutagen Society}, issn = {2476-7204}, eissn = {2476-6615}, doi = {10.22090/jwent.2017.04.003}, abstract = {Large quantities of oily wastewaters can be generated from the activities and processes in the petroleum industry which draining of these effluents not only pollutes the environment but also reduces the yield of oil and water. Therefore, development of treatment processes for petroleum industry wastewaters is vital in order to prevent serious environmental damage and provide a source of water for beneficial use. Reverse osmosis (RO) can be the most common membrane process used for desalination from oily wastewater and can produce water suitable for reuse at the petroleum industry. In this study, the application of RO technology for the petroleum industry wastewater treatment in different laboratory, pilot, field, and industrial scales have been reviewed. In addition, membrane fouling control, performance efficiency, treatment system configurations, pretreatment methods, quality of treated water, and economic issues have been investigated. With mixtures as complex as petroleum industry wastewaters, membrane fouling becomes a significant hurdle to implement the RO-based purification system. Operating the system within the critical flux range or adding chemicals, and/or pretreatment can usually control membrane fouling. Salt rejection of RO membranes can be 99% or higher.  }, keywords = {Petroleum,Reuse,Reverse osmosis,Treatment,Wastewater}, url = {https://www.jwent.net/article_28432.html}, eprint = {https://www.jwent.net/article_28432_8001d9f88010f7e8c8f0304d4c6b25c1.pdf} } @article { author = {Tanzifi, Marjan and Kolbadi nezhad, Marzieh and Karimipour, Kianoush}, title = {Kinetic and Isotherm Studies of Cadmium Adsorption on Polypyrrole/Titanium dioxide Nanocomposite}, journal = {Journal of Water and Environmental Nanotechnology}, volume = {2}, number = {4}, pages = {265-277}, year = {2017}, publisher = {Iranian Environmental Mutagen Society}, issn = {2476-7204}, eissn = {2476-6615}, doi = {10.22090/jwent.2017.04.004}, abstract = {The present work seeks to investigate the ability of polypyrrole/titanium dioxide nanocomposite to adsorb cadmium ions from aqueous solution. The impact of various experimental conditions, including solution pH, adsorbent dosage, adsorption time and initial concentration on the uptake of cadmium were studied. The adsorption kinetic was studied with the first-order, second-order, pseudo-first-order, pseudo-second-order and Morris–Weber models. The results revealed that adsorption process is controlled by pseudo-second-order model which illustrated that the adsorption process of cadmium is chemisorption-controlled. The adsorption capacity obtained from this model is 20.49 mg/g which close to the experimental value. The study yielded the result that when the initial concentration of the solution changed from 20 mg/l to 120 mg/l, the adsorption capacity increased from 0.99 to 24.52 mg/g. Further, Langmuir, Freundlich and Temkin isotherm models were applied to investigate the adsorption isotherm. Based on the results of the adsorption isotherm, Freundlich isotherm proved to be the best fit with the experimental data. Also, the morphology, chemical structure and thermal stability of adsorbent were studied by using SEM, EDX, FTIR, and TGA.  }, keywords = {Adsorption,Cadmium,Isotherm,kinetic,Polypyrrole,Titanium dioxide}, url = {https://www.jwent.net/article_28433.html}, eprint = {https://www.jwent.net/article_28433_ca8b25426d186627b1763a0525f56c6f.pdf} } @article { author = {Kouhiyan Afzal, Mohammad Taghi and Farrokhian Firouzi, Ahmad and Taghavi, Mehdi}, title = {Synthesis of Bare and Four Different Polymer- Stabilized Zero-Valent Iron Nanoparticles and Their Efficiency on Hexavalent Chromium Removal from Aqueous Solutions}, journal = {Journal of Water and Environmental Nanotechnology}, volume = {2}, number = {4}, pages = {278-289}, year = {2017}, publisher = {Iranian Environmental Mutagen Society}, issn = {2476-7204}, eissn = {2476-6615}, doi = {10.22090/jwent.2017.04.005}, abstract = {Zero-valent iron particles at the nanoscale are proposed to be one of the important reductants of Cr(VI), transforming the same into nontoxic Cr(III). In this study zero valent iron nanoparticles(ZVINs) were synthesized and characterized for hexavalent chromium removal from aqueous solutions. Five different zero-valent iron nanoparticle types comprising of bare and stabilized ZVINs with poly acrylamide(PAM), polyvinyl pyrrolidone(PVP), polystyrene sulfonate(PSS) and guar gum(GG) were synthesized and employed in this study. The sizes of zero-valent iron nanoparticles were found to be 40, 14, 17, 29 and 34nm, using transmission electron microscopy (TEM), corresponding to bare zero valent iron nanoparticles(ZVINs), poly acrylamide(PAM), guar gum(GG), poly styrene solfunate(PSS) and polyvinyl pyrrolidone(PVP) stabilized zero valent iron nanoparticles (ZVINs) respectively. The trend in the sizes of ZVINs with various stabilizers in the decreasing order was found to be bare ZVIN > PVP-ZVIN >PSS-ZVIN> GG-ZVIN> PAM-ZVIN respectively. Results showed that by increasing hexavalent chromium concentrations from 20 to 100 mg/L, the Cr(VI) efficiency removal decreased significantly. When the ZVINs concentrations increased from 2 to 10 gr/L(0.1 to 0.5g per 50 mL), the Cr(VI) removal efficiency enhanced. The most effective treatments of ZVINs and Cr(VI) for hexavalent chromium removal from solutions were 10 gr/lit (0.5g per 50 mL) and 20 mg/L respectively, so the efficiency of bare and polymer stabilized-ZVINs on Cr(VI) removal from solutions was found to be in the following order:  bare ZVINs < PVP-ZVINs 0.997) and low detection limits (0.006-0.32 ng mL-1). High enrichment factors are achieved ranging from 110 to 140. In the optimum experimental conditions, the established method is successfully applied for the determination of OPPs in spiked water samples (well, tap, shaft and canal) and apple juice. Satisfactory recovery results show that the sample matrices under consideration do not significantly affect the extraction process.   }, keywords = {Eggshell,Graphene quantum dots,Nano-Sorbent,Pesticides}, url = {https://www.jwent.net/article_28437.html}, eprint = {https://www.jwent.net/article_28437_9538f30755ca26fa9e306d4838d1f501.pdf} } @article { author = {Kazemimoghadam, Mansoor and Amiri-Rigi, Zahra}, title = {Application of Combined Cake Filtration-Complete Blocking Model to Ultrafiltration of Skim Milk}, journal = {Journal of Water and Environmental Nanotechnology}, volume = {2}, number = {4}, pages = {311-324}, year = {2017}, publisher = {Iranian Environmental Mutagen Society}, issn = {2476-7204}, eissn = {2476-6615}, doi = {10.22090/jwent.2017.04.008}, abstract = {Membrane ultrafiltration (UF) is widely used in dairy industries like milk concentration and dehydration processes. The limiting factor of UF systems is fouling which is defined as the precipitation of solutes in the form of a cake layer on the surface of the membrane. In this study, the combined cake filtration-complete blocking model was compared to cake filtration mechanism for flux data through ultrafiltration of skim milk at constant flow rate. The resistance data also was modeled using cake filtration model and standard blocking model. The effect of different trans-membrane pressures and temperatures on flux decline was then investigated. Based on the results obtained here, the combined complete blocking-cake formation model was in excellent agreement with experimental data. The cake filtration model also provided good data fits and can be applied to solutions whose solutes tend to accumulate on the surface of the membrane in the form of a cake layer. With increasing pressure, the differences between the model and experimental data increased.   }, keywords = {Flux Decline,Fouling,Milk Concentration,Modeling,Ultrafiltration}, url = {https://www.jwent.net/article_28439.html}, eprint = {https://www.jwent.net/article_28439_97ff1fafd22691666b8671dda15fa49e.pdf} }