توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Comparison Between Polysulfone and Polyethersulfone Membranes Prepared From PS&PES\DMAc\PVP System For Milk Concentration
نویسنده(ها): ،
اطلاعات انتشار: یازدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۶
In this study, polysulfone(PS) and polyethersulfone(PES) membranes were prepared from ternary systems containing PS or PES as polymer, N,N'– dimethylacetamide(DMAc) as solvent and polyvinylpyrrolidone(PVP) as additive. Phase inversion via immersion precipitation was employed for manufacturing of membranes. The prepared films were immersed in the mixture of pure water and 2–propanol (30\70 v%) as non–solvent. The morphology and performance of the prepared membranes were investigated by scanning electron microscopy and separation experiments using milk as the feed. The results demonstrates that the PES membrane has the better water flux than the PS membrane but the PS membrane shows the high resistance in opposite to protein fouling.<\div>

۲Thin film composite co–polyamide nanofiltration membranes: preparation and characterization
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۶
In the current study, a novel thin film composite nanofiltration membrane was prepared by interfacial polymerization and evaluated for water softening. Its nanofiltration performance was evaluated by cross flow filtration using NaCl (1 g\l) and MgSO4 (1 g\l) solution at 5 and 10 bars, 25 °C and 10 l\min. The morphological study was investigated by SEM and AFM. In addition, Thin–film composite polyamide nanofiltration membrane was fabricated using interfacial polymerization of piperazine with trimesoyl chloride (TMC) onto PES ultrafiltration membrane prepared with immersion precipitation technique. A rough, dense was formed on the PES support membrane by interfacial polymerization. The water permeability of composite membrane was 50 and 178 kg.m−2.h−1 at 5 and 10 bars, respectively. Moreover, the rejection to the divalent salt MgSO4 (74 and 80%) was high compared to the monovalent salt NaCl (55 and 59%).<\div>

۳fabrication of highly permeable polyamide composite nanofiltration membranes for water softening
نویسنده(ها): ، ،
اطلاعات انتشار: کنفرانس بین المللی آب و فاضلاب، سال
تعداد صفحات: ۱۰
The aim of this paper is to survey additive effect to produce highly permeable thin film compodite TFC polyamide nanofiltration membrane in water softening. TFC polyamide nanofiltration membranes were fabricated via interfacial polymrization of 1.3–phenylenediamine mPDA and trimesoyl chloride TMC on porous polyethersulfone PES membrane. it should be mentioned that the PES membrane was fabricated in bench –scale. the nanofiltration membranes were characterized by atomic force microscopy AFM, scanning electron microscopy PEM and cross flow filtration .<\div>

۴Design and fabrication of pilot scale system using membrane technology for yeast industry wastewater treatment
نویسنده(ها): ، ،
اطلاعات انتشار: کنفرانس بین المللی آب و فاضلاب، سال
تعداد صفحات: ۹
Generally, the wastewater from the yeast industry is characterized by high chemical and non–biodegradable organic pollutants. Most of the contaminants in the wastewater are due to the use of molasses as a main raw material. The treatment of the yeast industry wastewater was investigated by nanofiltration (NF) membrane process on a pilot scale. Two wastewaters were used as feed for this system: (i) dilute wastewater with COD 2000 mg\L and (ii) concentrate wastewater with COD 8000 mg\L. The permeate flux, COD retention, color and electrical conductivity (EC) removal were evaluated in relation to trans–membrane pressureand long–term filtration. A linear increase in permeate flux was found with increase in transmembrane pressure for wastewaters. In addition, the COD retention, color and EC removal increased with increase in trans–membrane pressure. The quality of permeate in term of COD is above the discharge standard in river (200 mg\L). Thus, this process is useful for treatment of wastewaters produced by yeast industry.<\div>

۵PULPAND PAPER WASTEWATER RTEATMENT VIA OPTIMIZED POLYVINYLALCHOLE (PVA)\POLYETHERSLFUNE (PES)COMPOSITE NANOFILTRATION MEMBRANES
نویسنده(ها): ، ،
اطلاعات انتشار: کنفرانس بین المللی آب و فاضلاب، سال
تعداد صفحات: ۷
the pulp and paper industry is one of the contributors of watewater pollution. The ultimate aim of this paper is to reduce the COD amount of pulp and paper industry wastewaters by nanofiltration PES\PVA membranes which were synthesized and cross –linked with maleic acid MA. PVA\PES composite nanofiltration membranes were prepared by dipping of the support PES membrane in the polyvinyl alcohol PVA and cross – linking solutions. maleic acid MA was used as cross –linking agent. the concentrations of PVA and MA were 0.5–2 and 0.05–1 wt% respectively. the SEM images indicated that the PVA layer was formed on the PES support membrane.<\div>

۶Preparation of hydrophilic ultra filtration membrane using Diaminobenzoic acid as additive in the casting solution
اطلاعات انتشار: سومین کنفرانس علوم و مهندسی جداسازی، سال
تعداد صفحات: ۱۱
This study was aimed to prepare hydrophilic ultrafiltration membranes to overcome the fouling problem in waste water treatment systems. Polyehtersulfone was selected as main polymer due to its good properties in membrane structure. Polyvinylpyrrolidone (PVP) was added to the casting solution as pore former and pore size controller. Hydrophilic agent used in this study was Diaminobenzoic acid (DBA) which is well known for its amine and hydroxyl containing structure. Membranes were prepared by phase inversion–precipitation method. Permeability and flux analysis were held using dead–end filtration cell. Rejection of humic acid (HA) was calculated by measuring absorbance of membrane permeates using UV–spectrophotometer. Common resistance parameters were calculated to check the fouling trend of different prepared membranes. Morphological properties of modified membranes were observed by atomic force microscopy (AFM) scans. Flux measurements showed increment in permeability for both distillated water and humic acid (as a selected model for protein macromolecule) by increasing DBA weight percent while rejection trend did not have unit growth or decrease. Smoother surfaces were obtained by checking the roughness parameters of AFM scans. As a result polyethersulfone ultrafiltration membrane with 8% DBA seemed to show better performance than other membranes<\div>

۷Synthesis of Polyaniline\Carbon nanofiber Nanocomposite in an aqueous media
اطلاعات انتشار: چهاردهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۵
Polyaniline\carbon nanofiber(PANI\CNF) nanocomposite was prepared in aqueous media by the chemical oxidative polymerization of aniline using carbon nanofiber as a filler.the morphologyand particle size of the product Was investigated by using scanning electron Microscope (SEM)and atomic force microscope (AFM). The chemical structure were studied by fourier transform infrared(FTIR) spectroscopy.the conductivity of nanocomposite was measured by four probe conductivity measurement. it was found that the resulting product particle size,conductivity and morphology affected by addition of carbon nanofiber.<\div>

۸Modeling of Nanofiltration System of Olive Mill Wastewater Treatment by Artificial Neural Network (ANN
اطلاعات انتشار: چهاردهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۵
In this study artificial neural network (ANN) as a powerful tool for resolving complex problems is used to predict permeate flux and COD removal in Olive oil mill wastewater (OMW) treatment byNF membranes. Network training was realized using measured data in our previous study. Tryingvarious types of the network structures, a network with one hidden layer including 7 neurons was found to be target. Performance of the ANN model was investigated with statistical analysis. Theresults showed that there is an excellent agreement between the measured data and the predicted values, with high correlation (R2 = 0.9923) and less mean squared error (MSE = 1.2E−4).<\div>

۹Application of TiO2 Coated layer on Polysulfone Sublayer For Thin Film Composite Membranes
نویسنده(ها): ،
اطلاعات انتشار: چهاردهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۱۰
In a new approach, thin film composite membranes were fabricated by investigating TiO2 nano–particles which were hidden completely between the polamide thin film and the polysulfone support layer. Scanning electron microscopy and atomic force microscopy were used to study cross section and surface morphological properties of NF membranes. wettability of the surface was obtained from contact angle measuring instrument. Permeability and salt rejection of membranes were tested using dead end filtration cell. Antifouling property of membranes was examined by filtration of pepsin solution as a model foulant and measuring total resistance and flux recovery ratio parameters. Morphological studies showed that the new NF membranes showed acceptable thin film formation (compact and smooth surface). Performance experiments of new antibacterial TFC membranes showed good permeability without scarifying the salt rejection. More resistance to the fouling appeared on the surface of new NFs due to the higher hydrophilicity and smoother surface. Antibacteriality of fabricated membranes was tested by disk diffusion method<\div>

۱۰Treatment of cheese whey wastewater: combined coagulation and adsorption
اطلاعات انتشار: دومین همایش ملی و تخصصی پژوهشهای محیط زیست ایران، سال
تعداد صفحات: ۱۱
Cheese whey wastewater is characterized by high chemical oxygen demand (COD) and other pollution load. Treatment of wastewater was investigated using coagulation and adsorption. Ferric chloride was used as a coagulant in the process. The COD and total dissolved solids (TDS) were removed mainly through coagulation 21–24% and 24–27%, respectively. These results can be achieved by using the coagulant dosage (200 mg L–1) in the optimum pH range (around 7.5). Adsorption by activated carbon can remove organic carbon (31–34%). Langmuir and Freundlich models were then employed to correlate the equilibria data on which both models equally well–fit the data. For kinetic data, pseudo–first and second order models are selected. Both physisorption and chemisorption play important roles for adsorption onto activated carbon. The coagulant treatment was followed by activated carbon treatment can reduce COD (53–55%).<\div>

۱۱A new concept to preparation of thin film nanocomposite nanofiltration membrane by interfacial polymerization as an approach to solve biofouling problem
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۹
This paper aims to development of a new concept for formation of mixed matrix nanofiltration (NF)membranes by interfacial polymerization of nanocomposite thin films on porous polyethersulfone support. Nanocomposite films created for this study comprise silver (Ag) nanoparticles embeddedwithin ultra thin polyamide films in order to produce antibacterial properties. Thin film composite (TFC) polyamide membranes exhibit a rough and dense film was formed on the PES support membrane, whereas thin film nanocomposite membranes have measurably rougher and larger poresize. At the 0.05 wt.% Ag nanoparticles loadings, nanocomposite film morphology is visibly different and water flux is much more that of polyamide membranes with slight decrease in salt rejections. A quantitative method was used to investigate the antibacterial properties of the nanocompositemembranes. The optical density decreases with increasing the number of circles meaning that the antibacterial effect becomes more obvious. As a concept, thin film nanocomposite membrane technology may offer new degrees of freedom in tailoring NF membrane separation performance and antibacterial properties<\div>

۱۲Optimization of synthesis conditions for brackish water ion elimination by TiO2 coated PVA\PES nanofiltration membranes using Taguchi approach
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۶
This study has applied the L16 orthogonal array of the Taguchi method to determine the optimal combination of three basic controlling material (PVA (poly–vinyl alcohol),Gluteraldehyde,TiO2 nanoparticles) concentration of synthesized PVA\PES composite membrane. PES ultrafiltrationmembrane was modified with so–called materials via dip–coating method .Taguchi approach was employed for ion rejection optimization. The optimum conditions were found as the second level of PVA, first level of Glu and fourth level of TiO2. surcace analysis of modified and virginmembranes were conducted with SEM (scanning electron microscopy) and contact angle measurements<\div>

۱۳Development of olive mill wastewater treatment by novel functionalized carbon nanotube\polyethersulfone ultrafiltration membrane
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۹
Olive oil mill wastewater (OMW) is known as the highest organic loads of concentrated effluents,especially with high organic chemical oxygen demand (COD). Membrane processes for wastewater treatment have several advantages, which their use is strongly justifiable. However, One common problem of membrane filtration is fouling that strongly affect on membrane performance and selectivity. In order to overcome these problems different pretreatmentswere used. In this work the novel UF membranes with different concentration of Functionalized Multi Wall Carbon Nano Tube (F–MWCNT) were used for OMW treatment due to attain high COD removal. Theeffects of operatinon parameters including pressure and temperature have been investigated on the UF system flux permeation and COD removal. The Taguchi method was applied to design of experiment and optimization. Under the optimum operation conditions suggested by Taguchi, flux and COD removal of UF filtration were obtained 18.1 (kg\m2 hr) and 40.6%, respectively, which were conformed with the predicted results by Taguchi (17.3 kg\m2 hr and 39.9% for flux and COD removal, respectively). The observed results show that the most important parameter is membrane type which the using CNT in the matrix of PES UF membranes was improved COD removal considarably<\div>

۱۴Comparing the effect of contact time at Nickel(II) adsorption on poly(styrene–co divinyl benzene) beads before and After functionalization
اطلاعات انتشار: پانزدهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۴
poly (styrene–co–divinylbenzene) with high amounts of cross–linker (DVB) and diverse proportions of diluent agent (porogen) are synthesized according to the methodology of the suspension polymerization technique. Also it was functionalized by sulfuric acid. The applicability of poly(styrene–co–divinyl benzene) beads to separation and concentration of Ni(II) is discussed. In separation of Ni(II) from aqueous solution the effect of contact time for poly(styrene–co–divinyl benzene) beads before and after functionalization are discussed. To measure the ion concentrationin the solution used the UV–vis spectrophotometer. It was found that the optimal conditions for Ni(II) separation from aqueous solution for poly (styrene–co–divinylbenzene) is 180 minute while after functionalization is 5 minute. So that with functionalization, therefore separation of Nickelions by ion exchange, adsorption process as well as improved.<\div>

۱۵Developing novel CTA\CA–based forward osmosis membrane containing hydrophilic nanoparticles
اطلاعات انتشار: دومین همایش ملی غشا و فرایندهای غشایی، سال
تعداد صفحات: ۵
Forward osmosis (FO) has developed as a new process with many potential applications in water production. The lack of an adequately designed membrane is the major challenge which hinders FO development. In this study, nanotechnology has been integrated with membrane science to build a high performance FO membrane. Boehmite nanoparticles, a hydrophilic additive containing extra hydroxyl groups on its surface, promoted cellulose acetate\cellulose triacetate (CA\CTA)–based membrane performance for FO applications. The characterization of the resultant nanocomposite membranes exhibited improved physiochemical properties, structural parameter and performance. Loading 0.5 wt. % of the nanoparticles enhanced the water permeability about three times without a considerable increase in salt permeability and produced an excellent permselectivity compared to the neat membrane. Moreover, the nanoparticles loading improved porosity of the nanocomposite membrane and reduced its structural parameter (S) to 0.53 mm. Higher porosity and desirable hydrophilicity of the modified membrane exhibited a reduced impact of internal concentration polarization (ICP), which generally influence FO processes. The performance results indicated that the modified membrane showed a superior FO performance compared to the commercially available FO membranes.<\div>

۱۶SiO2 nanoparticles as good material to modification of polyethyleneimine–based nanofiltration membranes for dye removal from aqueous solution
اطلاعات انتشار: دومین همایش ملی غشا و فرایندهای غشایی، سال
تعداد صفحات: ۶
Thin film composite nanofiltration membranes were fabricated by interfacial polymerization of polyethyleneimine and triphthaloyldechloride on top surface of the polysulfone substrate. SiO2 nanoparticles were added to the aqueous solution with different content for modification of PEI–based NF membrane. Fourier transform infrared spectra of membranes showed the new functional groups on the surface of membrane due to the presence of SiO2 nanoparticles. The contact angle measurement confirmed the improvement on the hydrophilic properties of the surface. Scanning Electron Microscope images showed that the SiO2 nanoparticles well dispersed on the surface structure of the modified membranes. The roughness parameters indicated that the surface of the fabricated membranes became rougher after adding SiO2 nanoparticles. The fabricated membranes were examined by filtration of crystal violet aqueous solution. By adding SiO2 nanoparticles, the membrane performanceshowed growing trend in case of flux, but for rejection a slight decrease was observed at first, then it was changed to growing trend by the further increasing amount of SiO2 nanoparticles.<\div>
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