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The aim of this work was to synthesize nanocomposite membranes based on chitosan (CS) and cellulose acetate (CA) blends containing titanium dioxide (TiO2) nanoparticles and investigate their morphological, structural, mechanical, and thermal properties along with dye affinity ligand content for using potentially as bioadsorption applications. The samples were characterized by means of scanning electronic microscopy (SEM), energy dispersive X‐ray (EDX), Fourier transform infrared spectroscopy (FTIR), tensile, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and water contact angle (WCA). The SEM micrograph images showed a uniform and microporous morphology of the prepared membranes. FTIR analysis confirmed the presence of CA and TiO2 nanoparticles through the CS matrix in which the components used had good compatibility. The mechanical and thermal studies emphasized that strong interactions occurred between CS, CA, and TiO2 nanoparticles. Blending CS with CA and the addition of TiO2 nanoparticles enhanced the hydrophilic property of CS membranes, significantly. The CS/CA based nanocomposite containing 1.5 wt% of TiO2 nanoparticles showed the remarkable improvements in ultimate tensile strength values and an increase in stiffness more than three times compared to the neat CS membrane sample. Finally, considering the results of tensile test and immobilized Cibacron Blue F3G‐A (CB) content measurement, the nanocomposite samples denoted by (50/50) CS/CA/TiO2 (1.5%) were nominated as the promising material used for potentially bioadsorptive membrane. POLYM. COMPOS., 39:4452–4466, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The aim of this study is the synthesis of a magnetic nanocomposite membrane to reduce fouling in a magnetic membrane bioreactor. To this end, Fe 3 O 4 nanoparticles with an approximate size of 60–70 nm were settled into the polysulfone ultrafiltration membrane matrix through blending of Fe 3 O 4 nanoparticles with the dope solution. Nanocomposite membranes containing 0–0.11 wt% Fe 3 O 4 nanoparticles submerged in the magnetic bioreactor system in which the MLSS was considered between 8000–16,000 g/L and the magnetic field intensity was 40–160 mT. The results showed that an increase in the concentration of nanoparticles reduced the filtration resistance as much as 48% and developed the COD removal as much as 24% and increased the flux as large as 30%. The presence of a magnetic field around the bioreactor reduced the total filtration resistance as much as 68% and increased the COD removal as much as 34% due to the production of some changes in the membrane morphology and the sludge properties. Comparing the performance of the synthesized nanocomposite membranes with a MICRODYN-NADIR commercial membrane sample showed that magnetic nanocomposite membranes possess 30% higher flux, 27% lower filtration resistance, 41% higher COD removal compared to a commercial membrane. [ABSTRACT FROM AUTHOR]

In this study the effects of Al2O3 nanoparticle concentration were investigated on the membrane structure/performance; the boundary of variations was detected, introduced as Nanoparticle Concentration Threshold (NCTh), and was used for forecasting the field of membrane application. For this purpose, Al2O3 nanoparticles with a size of 70 nm and a concentration between 0 and 0.52 Wt.% were added to the membrane matrix. Loading threshold of Al2O3 nanoparticles was evaluated and the properties of the nanocomposite membrane were compared up and sub the loading threshold. Rheometric analysis, contact angle measurement, SEM images, and filtration experiments showed that concentration threshold of Al2O3 nanoparticles was 0.39 Wt.%. Based on their properties, the antifouling performance of those membranes possessing Al2O3 concentration below the threshold was evaluated in a membrane bioreactor (MBR). [ABSTRACT FROM AUTHOR]

In this work, separation of disperse dyes and polyethylene glycol (PEG) as organic contaminant by nanocomposite membrane was investigated. The main goal of this study is to achieve more efficient separation of contaminant from water at high fluxes. For this purpose, iron oxide nanoparticles (NP) were synthesized through co-precipitation, blended with polysulfone/N-methylpyrrolidone solution, and finally, dispersed in membrane structure after coagulation of casted polymeric solution. Effect of magnetic nanoparticle concentration on membrane structure and filtration performance was studied. According to filtration experiments, the increasing of nanoparticle concentration in membrane matrix cause permission flux to raise. On the other side, any increases in magnetic nanoparticle content improved disperse dyes and PEG rejection as organic contaminant. Iron oxide NP in polymeric solution act as an agent to increase viscosity and cause a delay in phase inversion, decrement in membrane pore size, and finally, solute rejection enhancement. The Fourier transform infrared spectroscopy confirmed nanoparticle existence in membrane matrix. Furthermore, the magnetic properties of nanocomposite membranes were measured by Vibrating Sample Magnetometer. Scanning electron microscopy images showed the effect of nanoparticle concentration on membrane porosity. The cross section of which confirmed the role of NP as a delay agent in membrane formation. [ABSTRACT FROM PUBLISHER]

In this research, to benefit from the hydrophilic properties of zirconia nanoparticles as well as the role of iron oxide nanoparticles in improving porosity of polymer membranes simultaneously, Fe 3 O 4 @ZrO 2 /PAN nanocomposite membrane was synthesized and its performance was examined in reducing biological fouling of the membrane. FESEM analysis confirmed a size distribution of 35–55 nm, and TEM analysis confirmed a core-shell structure for Fe 3 O 4 @ZrO 2 nanoparticles. FTIR analysis identified the functional groups in the Fe 3 O 4 @ZrO 2 nanoparticles and confirmed their presence in the matrix of 1 Fe 3 O 4 @ZrO 2 /PAN NCM membrane. Contact angle analysis confirmed the role of zirconia nanoparticles in enhancing the membrane hydrophilicity by 51%, and porosimetry analysis confirmed the role of iron oxide nanoparticles in improving porosity of nanocomposite membranes by 47%. Usage of 1 wt% of Fe 3 O 4 @ZrO 2 nanoparticles in the PAN membrane matrix brought about 40% increase in water flux and 37% growth in dye rejection for 1Fe 3 O 4 @ZrO 2 /PAN NCM membrane. Investigation of the role of Fe 3 O 4 @ZrO 2 nanoparticles in the filtration of biological macromolecules indicated that 1 Fe 3 O 4 @ZrO 2 /PAN NCM membrane has 60%, 51%, and 56% less resistance to filtration of humic acid, sodium alginate, and BSA, respectively, when compared with raw membranes. [ABSTRACT FROM AUTHOR]