scholarly journals Recent Progress in Charged Polymer Chains Grafted by Radiation-Induced Graft Polymerization; Adsorption of Proteins and Immobilization of Inorganic Precipitates

2020 ◽  
Vol 4 (2) ◽  
pp. 20 ◽  
Author(s):  
Ryo Ishihara ◽  
Shiho Asai ◽  
Kyoichi Saito

Radiation-induced graft polymerization provides industrially superior functionalization schemes by selection of existing polymer substrates and design of graft chains. In this review, by a pre-irradiation method of the radiation-induced graft polymerization and subsequent chemical modifications, charged polymer chains grafted onto various components and shapes of the polymer substrates are described. The charged graft chains immobilized onto a porous hollow-fiber membrane captured proteins in multilayers via multipoint binding. A membrane onto which positively charged graft chains are immobilized, i.e., an anion-exchange porous hollow-fiber membrane, was commercialized in 2011 for the removal of undesirable proteins in the purification of pharmaceuticals. On the other hand, a membrane onto which negatively charged graft chains are immobilized, i.e., a cation-exchange porous hollow-fiber membrane, exhibited a low permeation flux for pure water; however, the prepermeation of an aqueous solution of magnesium chloride through the membrane restored the permeation flux because of ionic crosslinking of graft chains with magnesium ions. The charged graft chains provide a precipitation field for inorganic compounds such as insoluble cobalt ferrocyanide. The graft chains entangle or penetrate a precipitate owing to electrostatic interactions with the surface charge on the precipitate. Braids and wound filters composed of insoluble-cobalt-ferrocyanide-impregnated fibers are used for the removal of radiocesium from contaminated water at Tokyo Electric Power Co. (TEPCO) Fukushima Daiichi Nuclear Power Plant.

2006 ◽  
Vol 81 (3-4) ◽  
pp. 190-196 ◽  
Author(s):  
Hidetaka Kawakita ◽  
Kazuya Uezu ◽  
Satoshi Tsuneda ◽  
Kyoichi Saito ◽  
Masao Tamada ◽  
...  

2012 ◽  
Vol 152-154 ◽  
pp. 574-578 ◽  
Author(s):  
Ping Lan ◽  
Wei Wang

Polyethersulfone (PES) hollow fiber membranes have been widely used in many fields, such as ultrafiltration, microfiltration, reverse osmosis, liquid/liquid or liquid/solid separation, gas separation, hemodialysis, and so on. In this paper, the sheet PES hollow fiber membranes were prepared. The morphology and performance of membranes can be controlled. By studying the influence of the compositions and conditions on the morphology and performance of PES hollow fiber membrane, the relationship of morphology and performance of the membrane is acquired. The additives were used such as glycerol, BuOH and PEG. In addition, immerse phase inversion was used as membranes preparation method. The morphology of the membrane was controlled by changing kinds of additive, concentration of additive and so on. It was found that the membrane morphologies were changed by additive obviously. Porosity , pure water flux, scanning electron microscopy(SEM) were used to characterize the morphology and performance of the membranes.


2007 ◽  
Vol 56 (12) ◽  
pp. 111-118 ◽  
Author(s):  
Tang Li ◽  
Tan Xue-jun ◽  
Cui Fu-yi ◽  
Zhou Qi ◽  
Yin Jun

The particles from carwash wastewater were separated by a hollow fiber membrane aided by a enhanced coagulation and activated carbon. This study demonstrated that the addition of KMnO4 to coagulant (PAC) could enhance the efficiency of coagulation, which helped reduce clogging of the ultrafiltration membrane and activated carbon. The existence of LAS can loosen the gel layer on the membrane and improve the flux. Adsorption of particles such as organic matter and oil is the main reason causing membrane flux decrease. When carwash wastewater was pretreated, the permeation flux of membrane showed a higher value. LAS, odour and colour are removed by GAC adsorption treatment at last. The COD, BOD, LAS and oil of reuse water was 33.4 mg/L, 4.8 mg/L, 0.06 mg/L and 0.95 mg/L, respectively.


2012 ◽  
Vol 528 ◽  
pp. 210-213 ◽  
Author(s):  
Xuan Wang ◽  
Hao Long Bai ◽  
Li Ping Zhang

Nanocrystalline cellulose was used to blend with polysulfone to improve the hydrophicility and mechanical properties of PS hollow fiber ultrafiltration membrane. The method of dry-jet/wet-spining was adopted to form the hollow fiber by the mechanism of phase-inversion. In addition, the content of NCC was increased gradually from 0% to 1 wt% to examin the permeation flux, rejection ratio of bovine serum albumin(BSA) and mechanical strength of PS hollow-fiber. We find that the pure water flux was soared when NCC content was increased. The tensile strength and elongation at break were also detected and calculated. The results indicated that the properties of PS hollow-fiber membrane with appropriate NCC content were enhanced. The hollow fiber membranes were also observed with scaning electron microscopy(SEM) to explore the porous structure


Author(s):  
S. A. Mousavi ◽  
Z. Arab Aboosadi ◽  
A. Mansourizadeh ◽  
B. Honarvar

Abstract Wetting and fouling have significantly affected the application of membrane distillation (MD). In this work, a dip-coating method was used for improving surface hydrophobicity of the polyetherimide (PEI) hollow fiber membrane. An air gap membrane distillation (AGMD) process was applied for treatment of the methylene blue (MB) solution. The porous PEI membrane was fabricated by a dry-wet spinning process and the hydrophobic 2-(Perfluoroalkyl) ethanol (Zonyl® BA) was used as the coating material. From FESEM, the modified PEI-Zonyl membrane showed an open structure with large finger-like cavities. The modified membrane displayed a narrow pore size distribution with mean pore size of 0.028 μm. The outer surface contact angle of the PEI-Zonly membrane increased from 81.3° to 100.4° due to the formation of an ultra-thin coated layer. The pure water flux of the PEI-Zonyl membrane was slightly reduced compared to the pristine PEI membrane. The permeate flux of 6.5 kg/m2 h and MB rejection of 98% was found for the PEI-Zonyl membrane during 76 h of the AGMD operation. Adsorption of MB on the membrane surface was confirmed based on the Langmuir isotherm evaluation, AFM and FESM analysis. The modified PEI-Zonyl membrane can be a favorable alternative for AGMD of dyeing wastewaters.


Water ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1207 ◽  
Author(s):  
Nasrul Arahman ◽  
Suffriandy Satria ◽  
Fachrul Razi ◽  
M. Bilad

The efforts to improve the stability of membrane filtration in applications for wastewater treatment or the purification of drinking water still dominate the research in the field of membrane technology. Various factors that cause membrane fouling have been explored to find the solution for improving the stability of the filtration and prolong membrane lifetime. The present work explains the filtration performance of a hollow fiber membrane that is fabricated from polyethersulfone-2-(methacryloyloxy) ethyl phosphorylchloline while using a sodium alginate (SA) feed solution. The filtration process is designed in a pressure driven cross-flow module using a single piece hollow fiber membrane in a flow of outside-inside We investigate the effect of Ca and Mg ions in SA solution on the relative permeability, membrane resistance, cake resistance, and cake formation on the membrane surface. Furthermore, the performance of membrane filtration is predicted while using mathematical models that were developed based on Darcy’s law. Results show that the presence of Ca ions in SA solution has the most prominent effect on the formation of a cake layer. The formed cake layer has a significant effect in lowering relative permeability. The developed models have a good fit with the experimental data for pure water filtration with R2 values between 0.9200 and 0.9999. When treating SA solutions, the developed models fit well with experimental with the best model (Model I) shows R2 of 0.9998, 0.9999, and 0.9994 for SA, SA + Ca, and SA + Mg feeds, respectively.


2010 ◽  
Vol 150-151 ◽  
pp. 565-570 ◽  
Author(s):  
Yong Bo Shen ◽  
Ya Tao Zhang ◽  
Jian Hua Qiu ◽  
Yan Wu Zhang ◽  
Hao Qin Zhang

Hydrophilic poly((poly(ethylene glycol) methyl ether methacrylate) (P(PEGMA)) brushes were grafted from chloromethylated polyethersulfone (CMPES) hollow fiber membrane surface by surface-initiated atom transfer radical polymerization(SI-ATRP) to improve the membrane’s hydrophilic property. The CMPES hollow fiber membrane was prepared by phase inversion process. The benzyl chloride groups on the CMPES membrane surface could afford effective macroinitiators for grafting the well-defined polymer brushes. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy confirmed the grafting of P (PEGMA) chains. Field emission scanning electron microscopy (FESEM) was used to characterize the surface morphology of the CMPES membrane and modified membrane. The grafting yield of P (PEGMA) was determined by weight gain measurement. The results showed that the number-average molecular weight (Mn) of P (PEGMA) increased with the polymerization time. It was found that the grafting of P (PEGMA) brought higher pure water flux, improved water uptake ratio and better anti-protein absorption ability to CMPES membrane after modification.


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