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This work reports the alterations in the performance and morphology of a Nafion-based proton exchange membrane in the presence of three nano-Co3O4 morphologies (nanorod (R), nanosphere (S), and nanooctahedral (O)) modified by tetraethylorthosilicate (TEOS, T) and 3-aminopropyltriethoxysilane (APTES, A). The effects of surface chemistry and morphology of Co3O4 nanostructures on the properties of the as-prepared nanocomposite membranes were investigated by water uptake, proton conductivity, methanol permeability, and selectivity measurements. The methanol barrier properties of all nanocomposite membranes improved compared to the control Nafion membrane. The Nafion membranes embedded with aminosilica-functionalized Co3O4 also showed higher proton conductivity and improved methanol barrier properties compared to silica-functionalized Co3O4 and unmodified nanoparticles owing to the strong interaction between amino functionals on the surface of Co3O4 nanostructures and sulfonic moieties of the Nafion matrix. In particular, the incorporation of 5 wt % octahedral aminosilica-functionalized Co3O4 into the Nafion matrix provided the highest selectivity (15.2 × 104 S s–1 cm–3) and the lowermost methanol permeability (5 × 10–7 cm2 s–1), which were 3.6-fold higher and four times lower than that of the control Nafion membrane, respectively. [ABSTRACT FROM AUTHOR]

It is widely acknowledged that three‐dimensional (3D) printing or additive manufacturing will revolutionize many industries. However, the broad implications of 3D printing on water treatment membranes are not appreciated. 3D printing will transform the traditional membrane fabrication methods, reducing costs and industrial waste from manufacturing processes, with substantial benefits to treatment performance. In particular, 3D printing provides a high potential for radical decentralization. Remote communities, hospitality resorts, military bases, and oil and gas extraction operations could significantly benefit from the on‐site fabrication of membrane units tunable to their specific wastewater challenges. Acute drinking water contamination events, like those associated with toxic by‐products from algal blooms, chemical spills, forest fires, and extreme weather, cause adverse health effects on humans and shutdowns of piped water supply. 3D printing of customized membranes provides an opportunity for a fast response to such disastrous events. These membranes could be ready for installation within hours, with the vendor's role more akin to a software company installing a patch than the traditional approach, with major considerations for hardware availability, timeline, and supply chain. Despite these clear and potentially transformative advantages, 3D printing of membranes is not a panacea; countless aspects need to be taken into consideration for the successful implementation of this emerging technology. The full deployment of 3D‐printed membranes in water and wastewater treatment can be achieved by extending the variety of printable materials, improving the speed and resolution of printing, creating nanoscale pores, reducing the fabrication costs, and improving the mechanical properties of the resulting membranes. [ABSTRACT FROM AUTHOR]

Branched polyamides (BPAs) were prepared through a polycondensation method and then blended with poly(acrylonitrile) (PAN; 3:1) to construct the nanocomposite membranes having various concentrations of graphene oxide (GO) (2 and 5 wt%). The BPA/PAN and BPA/PAN/GO membranes were applied for selective removal of chlorinated volatile organic compounds (Cl-VOCs) from water by pervaporation. Impacts of feed composition, GO content and distinct feed types were investigated on pervaporation performance. Membranes were water selective and the permeation rate incremented with GO elevation. The highest permeation rate (203 g/m2 h) and separation factor (10) were detected for BPA/PAN/GO-5 nanocomposite membrane containing 5 wt% GO for separating the pentachloroethane/water mixtures at 30 °C for 0.1 wt% pentachloroethane in feed. Separation of pentachloroethane/water mixture proceeded easier than those of 1,1,1,2-tetrachloroethane/water, trichloroethylene/water, and 1,2-dichloroethylene/water mixtures because of the larger molecular size of pentachloroethane. [ABSTRACT FROM AUTHOR]