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In this study, wastewater treatment was destined for generation of electricity and hygienic water by an innovative integrated microbial fuel cell – membrane separation process (MFC-MSP). An optimal antifouling nanofiltration membrane (blended with O - carboxymethyl chitosan bound Fe 3 O 4 magnetic nanoparticles (CC Fe 3 O 4 NPs)), an antifouling ultrafiltration (UF) membrane (blended with polycitrate-alumoxane nanoparticle (PC-A)) and a high efficiency proton exchange membranes were applied in MSP and MFC processes. Firstly, the performance of MFC unit under different operating conditions of reaction time (RT), mixed liquor suspended solid (MLSS) concentration and influent chemical oxygen demand (COD) concentration was investigated in terms of COD removal efficiency and power generation for synthetic dairy wastewater treatment. The experiments were modeled using response surface methodology (RSM). The results indicated that by increasing in RT and COD in concentration, the COD removal was decreased. Also, the high concentration of MLSS in anodic chamber led to high COD removal efficiency. By increasing of MLSS beyond 3000 mg/L, the maximum power generation was decreased that reveals an adverse impact of biofouling on membrane performance. After primary treatment in anodic chamber of MFC at optimum condition, the anodic chamber effluent was passed through the membranes in two modes, direct nanofiltration (NF) membrane and UF-NF membranes in series. The results indicated that the UF membrane alleviated the organic loading of NF membrane by 72% relative to the direct NF filtration. The permeation flux shows a sustain performance of the NF when is coupled with UF membrane.a. [ABSTRACT FROM AUTHOR]

In this study, polyethersulfone (PES) nanofiltration membranes were synthesized by blending of O-carboxymethyl chitosan/Fe3O4 nanoparticles via the phase inversion method. O-carboxymethyl chitosan bound Fe3O4 magnetic nanoparticles (CC-Fe3O4 NPs) were synthesized by the binding of carboxymethyl chitosan (CC) onto the surface of Fe3O4 magnetic nanoparticles via co-precipitating method. The modified membranes had considerably higher pure water flux and permeation compared to the unfilled PES membrane. Surface hydrophilicity of the modified membranes was improved due to water affinity improvement of the membrane surface. However, high content of CC-Fe3O4 NPs (> 0.5%) in the casting solution diminished membrane performance due to agglomeration of the nanoparticles in the polymer matrix. The antifouling properties of the membranes were evaluated by powder milk solution and measuring the pure water flux recovery ratio (FRR). The 0.5 wt.% CC-Fe3O4 NPs-PES membrane exhibited the highest FRR value (91.7%) and the lowest irreversible fouling resistance (Rir) value (8.33%). Nanofiltration performance was also examined by retention of Direct Red 16 dye. As a conclusion, the addition of CC-Fe3O4 NPs at lower concentration could result in membranes with superior pure water flux, higher rejection and good fouling resistance compared to the unfilled PES membrane. [ABSTRACT FROM AUTHOR]

Highlights: [•] Superhydrophobic NF membrane was prepared by coating MWCNT/PDMS on PVDF membrane. [•] SDS and Triton X-100 surfactants were used for homogenous dispersing of MWCNT. [•] Pure water flux was reduced by increasing concentration of PDMS. [•] AFM images revealed that the MWCNTs inserted membrane possesses rougher surface. [•] The prepared membranes showed high flux recovery ratio and antifouling properties. [Copyright &y& Elsevier]

In this study, a polyamide membrane (NF-CSM 4040 commercial membrane) was examined in the treatment of baker's yeast wastewater (BYW). The response surface methodology (RSM) used in the present study was a face-centered central composite design (CCFD). The nanofiltration process was analyzed and modeled with three numerical independent factors, namely concentration of feed chemical oxygen demand (COD) (1000–5000 mg/L), pH (3–9) and operating pressure (3–6 bar) using RSM. In order to analyze the process, two dependent parameters (flux and rejection) were studied as the process responses. Concentration of feed COD had a reverse impact on flux and rejection, while pH did not show a significant effect on the responses. The operating pressure showed a sharp increasing effect on flux. Maximum flux was found to be about 37 kg/m2.h, at a concentration of feed COD of 1000 mg/L, an operating pressure of 6 bar and a pH of 6. Maximum rejection (91%) was obtained at a COD of 5000 mg/L, a pH of 6 and an operating pressure of 3 bar. Consequently, the membrane technology could be a promising approach to the removal of natural dye from BYW. [ABSTRACT FROM AUTHOR]

• β-CD/MWCNTs nanocomposite was synthesized using a soft cutting method. • PES based mixed matrix NF membranes were prepared using the β-CD/MWCNTs nanocomposite. • The prepared NF membranes exhibited better hydrophilicity, dye rejection and antifouling capability. In this research, the manufacture and properties of polyethersulfone (PES)-based mixed matrix nanofiltration (MM-NF) membranes modified with β-cyclodextrin functionalized multiwalled carbon nanotubes (β-CD/MWCNTs) were studied. The β-CD/MWCNTs nanocomposite was synthesized using the soft cutting method. Stable dispersivity of the resulting nanocomposite was checked for 12 h. Then, the membranes containing up to 1 wt% β-CD/MWCNTs were prepared using conventional phase inversion method. The impact of varied mass loadings of the β-CD/MWCNTs on the morphological features and performance of the amended membranes was evaluated. It was deduced that membrane hydrophilicity, porosity, pore size, water contents, dye rejection and antifouling capacity were noticeably improved after incorporating the β-CD/MWCNTs nanomaterials. In comparison with the bare membrane, the β-CD/MWCNTs amended membranes displayed higher hydrophilicity, and consequently pure water flux (PWF). Since β-CD can exploit the structure advantages of MWCNTs via enhancement of the dispersivity, devoting unique features to the β-CD/MWCNTs nanomaterial. The 0.1 wt% nanocomposite membrane sample revealed the highest pure water flux of 21.5 Kg/m2.h due to increase in pore size (5.0 nm). While, the membrane contributed with the β-CD/MWCNTs-0.5 revealed better performance in terms of dye rejection and antifouling capability than the bare and modified membranes. It indicated a dye rejection of above 92%, flux recovery ratio (FRR) of 89% and an irreversible resistance of 11.1%. The β-CD/MWCNTs-0.5 acted as a potential nanofiller in nanofiltration (NF) membranes improving their antifouling performance at different operational conditions. [ABSTRACT FROM AUTHOR]