Fabrication and application of novel high strength sulfonated PVDF ultrafiltration membrane for production of reclamation water.

Advanced treated water (ATW) produced in wastewater treatment facilities was assessed as an excellent alternative water resource that can be used as reclamation water, such as indirect and direct potable reuse. The development of cutting-edge technology for simple but best practices is essential for the reliable production of safe reclamation water from wastewater. This study prepared a novel high strength sulfonated polyvinylidene fluoride (HSPVDF) ultrafiltration membrane and investigated to produce ATW, and performances were compared to sulfonated PVDF (SPVDF) (which was prepared without thermal treatment) and bare PVDF. To compare the properties of HSPVDF to hydrocarbon polymer, the polyetherimide (PEI) and Sulfonated PEI (SPEI) membrane were prepared. HSPVDF showed excellent membrane morphology, porosity, MWCO, and hydrophilicity, resulting in higher pure water flux (712 ± 6 L m-2 h-1) antifouling properties (Rir 1.3% and FRR 98.6%) compared to PVDF. It is an interesting fact that the tensile strength of the HSPVDF (3.4 ± 0.2 MPa) tremendously increased (3 folders) when compere to PVDF (1.3 ± 0.1 MPa). The HSPVDF membrane showed good removal efficiency up to 96 ± 05% and 97 ± 09% rejection for bovine serum albumin (BSA) and humic acid (HA), respectively. The membrane application studies for wastewater treatment showed that the tertiary HSPVDF UF membrane filtration following the nutrient removal activated sludge (NRAS) process can produce reliable and economic performance (125 ± 2 L m-2 h-1, 0.25 ± 0.05 NTU, no pathogens), suggesting that it can be a best practice technique that can replace the complicated multi-staged tertiary processes to produce reclamation water.

Genome characterization of the novel lytic genome sequence of the phage YUEEL01 of the Myoviridae family.

Antimicrobial resistance is a global concern because of its rapid emergence in the environment and the associated high risk to human and animal health. Municipal wastewater, including urban, hospital, and pharmaceutical effluent, is the primary source of contamination by antibiotics and antibiotic-resistant bacteria (ARB). Biological processes are commonly used for wastewater treatment. Biologically based strategies are a promising approach to effective integrated ARB control because they focus on antibiotic resistance. An effective bacteriophage against multi-drug resistance (MDR) microbes in municipal wastewater was.

Ameliorative photocatalytic dye degradation of hydrothermally synthesized bimetallic Ag-Sn hybrid nanocomposite treated upon domestic wastewater under visible light irradiation.

Industrial and textile dyes are the major source of water pollutants in the Coimbatore Districts of Tamil Nadu, India. The highly stable organic dyes from these industries are being discharged untreated into neighboring rivers, lakes, and ponds. Thus, the present study mainly focused on the preparation of bimetallic nanocomposite (Ag-Sn) through Free-facile Teflon autoclave methodology and their subsequent stimulation has given to the photocatalyst by visible light irradiation. This visible light stimulates and irradiates the photocatalysts from steady state to the excited state and might help in absorption of the nanosized dye materials and organic matter. The nanocomposite was characterized using UV, FTIR, Zeta-sizer, XRD and FE-SEM. These parameters exhibited significant lattice structures with an average size of 127.6 nm. Further the nanocomposite treated samples were tested for water quality parameters like TDS, BOD, COD, heavy metals, sedimentation rate and bacterial population. Likewise, the samples irradiated with visible light for photocatalytic activity exhibited a significant intensity of C/C0 at 0.42 and 0.28. The treated water used for green gram seedling assay exhibited significant growth. Scavengers from Ag-Sn bimetallic nanocomposite plays the major role in dye degradation. The results clearly suggest that Ag-Sn bimetallic nanocomposite can be used for wastewater treatment and the subsequent treated water can be utilized for agriculture purposes.

Facile one-pot microwave assisted synthesis of rGO-CuS-ZnS hybrid nanocomposite cathode catalysts for microbial fuel cell application.

A reduced graphene oxide-copper sulfide-zinc sulfide (rGO-CuS-ZnS) hybrid nanocomposite was synthesized using a surfactant-free in-situ microwave technique. The in-situ microwave method was used to prepare 1-D ZnS nanorods and CuS nanoparticles decorated into the rGO nanosheets. The prepared hybrid nanocomposite catalysts were analyzed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, elemental mapping analysis, and X-ray photoelectron spectroscopy. The effectiveness of the synthesized rGO-CuS-ZnS hybrid nanocomposite (rGO-CZS HBNC) was estimated using an innovative cathode catalyst in microbial fuel cell (MFC). MFCs were fabricated differently such as SL (single-layer), DL (double-layer), and TL (triple-layer) loading. Followed using cyclic voltammetry and impedance analyses, the electrochemical evaluation of the prepared MFCs was evaluated. Among the fabricated MFCs, the DL MFCs with rGO-CuS-ZnS cathode catalyst displayed higher power density (1692 ± 15 mW/m2) and OCP (761 ± 9 mV) than the other catalysts loadings, such as SL and TL. rGO-CZS HBNC are potential cathode materials for MFC applications.

Enhanced antifouling performance of PVDF ultrafiltration membrane by blending zinc oxide with support of graphene oxide nanoparticle.

This paper reports a novel nanocomposite additive for a polyvinylidene fluoride (PVDF) membrane with high hydrophilicity through the association of graphene oxide (GO) and ZnO. The influence of the hydrophilicity of GO-ZnO on the PVDF membrane was examined on different GO-ZnO loadings. The porosity and wettability (or hydrophilicity) of the membrane were improved significantly by blending GO-ZnO nanocomposite. In addition, the water flux of the GO-ZnO/PVDF membrane was 48% higher than that of bare PVDF, and the anti-fouling properties of this modified membrane were also improved. The irreversible fouling ratio (Rir) of bovine serum albumin (BSA) was reduced substantially with increasing the loading of GO-ZnO nanocomposite. The lowest irreversible fouling ratio (7.21%) was obtained for the membrane containing 0.2 wt % GO-ZnO of the nanocomposite (M6). GO-ZnO modification PVDF membranes were assumed to reduce the affinity between membrane and BSA foulant, which improved the anti-fouling properties PVDF membrane. In the activated sludge flux test, the membrane containing GO-ZnO in the polymer matrix had a higher flux than that of the bare PVDF membrane. The effluent quality after the composite membrane (0.6 NTU) was stable, indicating that the composite membrane can be used for practical applications Overall, the properties of the PVDF membrane were improved after modification due to hydrogen bonding or the hydrophilicity of the GO-ZnO nanocomposite.

Enhanced cathode performance of a rGO-V2O5 nanocomposite catalyst for microbial fuel cell applications.

A reduced graphene oxide-V2O5 nanocomposite was synthesized by a low temperature surfactant free hydrothermal method and its MFC performance was assessed. The structural properties of the synthesized nanocomposite were studied by X-ray diffraction. Field emission scanning electron microscopy of the nanocomposite revealed a wrinkled paper-like structure of rGO and a nanobelt-like structure of V2O5. This study estimated the viability of the graphene-based nanocomposite rGO-V2O5 as a novel cathode catalyst in single chamber air-cathode MFCs. A series of MFCs with different catalyst loadings were produced. The electrochemical behavior of the MFCs was calculated by cyclic voltammetry. The MFCs with the rGO-V2O5 nanocomposite cathode exhibited superior maximum power densities (83%) to those with the pure V2O5 cathodes. The rGO-V2O5 with a double-loaded nanocomposite catalyst achieved an enhanced power density of 1668 ± 11 mW m-2 and an OCP of 698 ± 4 mV, which was 83% of that estimated for the Pt/C 2004 ± 15 mW m-2 nanocomposite cathode. The significant increase in power density suggests that the reduced graphene oxide-V2O5 nanocomposite is a promising material for MFC applications. The CV result showed good agreement with the MFC result. The prepared rGO-V2O5 nanocomposite cathode, particularly with a double loading catalyst, is promising as a sustainable low-cost green material for stable power generation and long-term operation of MFCs.

Non-toxic properties of TiO2 and STiO2 nanocomposite PES ultrafiltration membranes for application in membrane-based environmental biotechnology.

In membrane bioreactor (MBR) technology, nanocomposite membrane has a great potential to improve the filtration performance and antifouling. However, antibacterial activity of nanoparticles (NPs) is a significant disadvantage which can be impacted to bacterial growth and microbial community in MBRs. The modified polyethersulfone (PES) ultrafiltration (UF) membranes in the study were prepared by using TiO2 NPs and TiO2 NPs functionalized with sulfonation (STiO2). The antibacterial effect of NPs and non-toxic properties of nanocomposite membranes were examined by using three different Gram-negative bacterial species isolated from a local full scale membrane bioreactor treating municipal wastewater (Escherichia coli, Pantoea agglomerans, and Pseudomonas graminis). Results are revealed that the TiO2 and STiO2 NPs have 60% of antibacterial activity based on disc diffusion, viability tests, and TEM analysis. However, the PES-TiO2 and PES-STiO2 nanocomposite UF membranes showed significantly lower antibacterial activity (<95%, significance at p < 0.0001), indicating innocuous to bacterial growth. This study highlights that the PES-TiO2 and PES-STiO2 nanocomposite membrane is more sustainable than PES membrane and promising materials for MBRs, by taking advantage of non-toxic properties to bacterial growth.

Enhanced response of microbial fuel cell using sulfonated poly ether ether ketone membrane as a biochemical oxygen demand sensor.

The present study is focused on the development of single chamber microbial fuel cell (SCMFC) using sulfonated poly ether ether ketone (SPEEK) membrane to determine the biochemical oxygen demand (BOD) matter present in artificial wastewater (AW). The biosensor produces a good linear relationship with the BOD concentration up to 650 ppm when using artificial wastewater. This sensing range was 62.5% higher than that of Nafion(®). The most serious problem in using MFC as a BOD sensor is the oxygen diffusion into the anode compartment, which consumes electrons in the anode compartment, thereby reducing the coulomb yield and reducing the electrical signal from the MFC. SPEEK exhibited one order lesser oxygen permeability than Nafion(®), resulting in low internal resistance and substrate loss, thus improving the sensing range of BOD. The system was further improved by making a double membrane electrode assembly (MEA) with an increased electrode surface area which provide high surface area for electrically active bacteria.

Development of MFC using sulphonated polyether ether ketone (SPEEK) membrane for electricity generation from waste water.

Polyether ether ketone was sulphonated polyether ether ketone (SPEEK) and utilized as a proton exchange membrane (PEM) in a single chamber MFC (SCMFC). The SPEEK was compared with Nafion® 117 in the SCMFC using Escherichia coli. The MFC with the SPEEK membrane produced 55.2% higher power density than Nafion® 117. The oxygen mass transfer coefficient (K(O)) for SPEEK and Nafion® 117 was estimated to be 2.4 × 10(-6)cm/s and 1.6 × 10(-5)cm/s, respectively resulting in reduced substrate loss and increased columbic efficiency (CE) in the case of SPEEK. When the dairy and domestic waste water was treated in SPEEK-SCMFC, fitted with a membrane electrode assembly (MEA), a higher maximum power density was obtained for dairy waste water (5.7 W/m(3)). The results of this study indicate that SPEEK membrane has the potential to greatly enhance the efficiency of MFCs.