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membrane-ultrafiltration
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Preparation and characterization of PVC/PAN blend ultrafiltration membranes: Effect of PAN concentration and PEG with different molecular weight
, Article Desalination and Water Treatment ; Volume 58 , 2017 , Pages 1-11 ; 19443994 (ISSN) ; Mojtaba Seyedi, S ; Rabiei, H ; Alvandifar, N ; Arya, A ; Sharif University of Technology
Desalination Publications
2017
Abstract
The current study investigates the effect of polyacrylonitrile (PAN) addition on morphology and antifouling properties of poly(vinyl chloride) (PVC) asymmetric flat ultrafiltration (UF) membranes. The membranes are prepared via phase inversion method induced by immersion precipitation at different PVC/PAN blending ratio up to 40 wt% PAN. Also, membranes with blending ratio of PVC/ PAN:70/30, which showed the highest water flux and flux recovery ratio, were used for membrane preparation with 4 wt% of Polyethylene glycol (PEG) addition in four different molecular weight, 600 Da, 1,000 Da, 6,000 Da and 20,000 Da, which was used as pore former and hydrophilic polymeric additive. The performance...
Chemical Engineering- Transport Phenomena and Separation Processes
, M.Sc. Thesis Sharif University of Technology ; Safekordi, Ali Akbar (Supervisor) ; Hemmati, Mahmoud (Supervisor)
Abstract
In this study, experimental results of Ahvaz produced water treatment obtained in ultrafiltration process using a polymeric membrane formed from Polyacrylonitrile (PAN) with 0.2 µm poreshave been reported. In this process the effects of different factors including transmembrane pressure (TMP), cross flow velocity (CFV) and feed temperature on permeate flux, membrane fouling resistance and TOC rejection was investigated. The results show that optimum conditionswere found in the range of TMP: 1.5-3 bar, CFV: 1-1.5 m/s and operating temperature 40°C.Results show that under optimum conditions the final permeate flux for produced water of Asmari outlet of Skimmer unit was 30 L/m2.h, and the...
Comparative assessment of the efficiencies of gas sparging and back-flushing to improve yeast microfiltration using tubular ceramic membranes
, Article Desalination ; Volume 217, Issue 1-3 , 2007 , Pages 93-99 ; 00119164 (ISSN) ; Tabaei, S. R ; Roostaazad, R ; Sharif University of Technology
2007
Abstract
Gas sparging and back-flushing treatments were compared as a means to tackle the problem of fouling in yeast microfiltration. Based on the feed and membrane characteristics, it was shown that either of these techniques could be superior to the other in order to overcome the problem. At more concentrated feed streams the main cause of flux decline was cake formation. In this condition gas sparging showed greater efficiency in flux enhancement. On the other hand at lower feed concentration the relative importance of internal fouling due to pore blockage, increased. In this case back-flushing was more effective. © 2007
Surface Modification of Ultrafiltration Membranes to Reduce Fouling in the Dairy Industry
, M.Sc. Thesis Sharif University of Technology ; Musavi, Abbas (Supervisor) ; Molaei Dehkordi, Asghar (Co-Supervisor)
Abstract
In the dairy industry, for the processing of raw milk, including the isolation of living bacteria and microorganisms from milk to increase the shelf life and improve the taste of milk, or the isolation of casein and whey proteins from milk for pHarmaceutical and medical purposes, as well as the production of low-lactose or lactose-free milk for patients with Digestive problems, use membrane processes, especially ultrafiltration and microfiltration, and the main problem in these methods is the fouling of the polymer membranes used, which results in the loss of flux or the reduction of product quality and system efficiency. With the help of bulk modification and surface modification of the...
Improvement in flux and antifouling properties of PVC ultrafiltration membranes by incorporation of zinc oxide (ZnO) nanoparticles
, Article Separation and Purification Technology ; Volume 156 , 2015 , Pages 299-310 ; 13835866 (ISSN) ; Vatanpour, V ; Davood Abadi Farahani, M. H ; Zarrabi, H ; Sharif University of Technology
Elsevier
2015
Abstract
In this study, modification of polyvinyl chloride (PVC) ultrafiltration membranes with zinc oxide (ZnO) nanoparticle addition was taken into consideration. The ZnO at five different weights was added to the polymeric solution, and the membranes were fabricated by the phase inversion method using water as a nonsolvent and PEG 6 kDa as a pore former additive. The results showed that the pure water flux of the modified membranes increased up to 3 wt% ZnO addition, which was the optimized amount of the nanoparticle addition in this study. Also, at 3 wt% ZnO addition, flux recovery ratio reached from 69% to above 90%, indicated that the nanocomposite membranes were less susceptible to be fouled....
Preparation of poly(vinyl chloride) (PVC) ultrafiltration membranes from PVC/additive/solvent and application of UF membranes as substrate for fabrication of reverse osmosis membranes
, Article Journal of Applied Polymer Science ; Volume 135, Issue 21 , 2018 ; 00218995 (ISSN) ; Asadollahi, M ; Musavi, A ; Bastani, D ; Sharif University of Technology
John Wiley and Sons Inc
2018
Abstract
Ultrafiltration (UF) membranes were prepared from poly(vinyl chloride) (PVC) as main polymer, poly(vinyl pyrrolidone) (PVP) as additive, and 1-methyl-2-pyrrolidone (NMP) as solvent using Design Expert software for designing the experiments. The membranes were characterized by SEM, contact angle measurement, and atomic force microscopy. The performance of UF membranes was evaluated by pure water flux (PWF) and blue indigo dye particle rejection. In addition, the molecular weight cutoff of UF membranes was determined by poly(ethylene glycol) (PEG) rejection. The UF membranes were used as substrates for fabrication of polyamide thin film composite (TFC) reverse osmosis (RO) membranes. The...
Metal organic framework nanoparticles loaded- PVDF/chitosan nanofibrous ultrafiltration membranes for the removal of BSA protein and Cr(VI) ions
, Article Journal of Molecular Liquids ; Volume 317 , 2020 ; Koushkbaghi, S ; Hosseini, S. S ; Darabi, M ; Yousefi, A ; Irani, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The UiO-66 NH2 and ZIF-8 metal organic framework nanoparticles (NMOFs) were incorporated into the polyvinylidene fluoride (PVDF) nanofibrous membrane. Then, the chitosan nanofibers were coated on the PVDF nanofibers to produce the PVDF/chitosan nanofibers. The performance of synthesized PVDF/NMOFs single layer and PVDF/chitosan/NMOFs two layers nanofibrous membranes was investigated for BSA protein molecules and Cr(VI) ions separation via ultrafiltration membrane process. The potential of synthesized nanofibers was also examined for BSA and Cr(VI) adsorption in a batch system. The characteristics of synthesized nanofibrous membranes were determined using SEM, EDX, TGA, BET, porosity and...