A high-performance thin-film composite polyamide membrane upcycled from a substrate fouled with a biopolymer and a preparation method thereof are provided. The method includes fouling the substrate preferably with the biopolymer to obtain a composite of the substrate and a biopolymer foulant layer; then immersing the composite into a first solution formed by dissolving a polyamine monomer in water, followed by taking the composite out of the first solution and removing excess droplets from a surface of the composite; then immersing the composite treated in the previous step into a second solution formed by dissolving an acyl chloride monomer in n-hexane for interfacial polymerization to form a rejection layer on the surface of the composite; and after completion of the reaction, taking the composite out of the second solution, followed by drying and heat treatment, to obtain the target polyamide membrane.

The present invention provides a nanocomposite coating comprising: a two-dimensional material; and a polymer, wherein the nanocomposite coating is semi-permeable and is for providing on porous material to improve selectivity towards one phase over others thereby enabling separation of that phase by mass transfer. There is also provided a phase transformation and mass transfer unit comprising porous material coated with the nanocomposite coating, and a low temperature liquid phase separation method comprising flowing liquid mixture through a phase transformation and mass transfer unit comprising porous material coated with the nanocomposite coating.

The present invention provides a multi-stage filter system suitable for the production of drinking water from a wide variety of contaminated water sources. The modular nature of the multi-stage filter system allows for the customization of filter combinations according to the remediation requirements. The multi-stage filter system comprises a coarse filter (S1); an ultrafiltration filter (S2); a graphene-based filter (S3); and a residual nanoparticle filter (S4). The graphene-based filter cartridge comprises few-layer graphene powder; a combination of few-layer graphene powder and pellets comprising a mixture of polyethersulfone, graphene oxide (GO), and dimethylformamide; a composite comprising chitosan, GO, sodium sulfate and ferric chloride; or a combination of few-layer graphene powder, granular activated carbon and a composite comprising chitosan, GO, sodium sulfate and ferric chloride.

A water filtration membrane is provided, capable of removing heavy metal ions, filtering out particulates, filtering out bacteria, as well as removing herbicides and volatile organic compounds (VOCs) from water. The membrane is composed of a mat of randomly oriented nanoparticle-coated nanofibers. The nanofibers are covalently bonded to a plurality of substantially uniformly-distributed ceramic nanoparticles embedded in or adhered on the surface of the polymer nanofibers through reactive functional groups. The ceramic nanoparticles have a pattern of deep grooves formed on the nanoparticle surfaces. The bonding of the nanoparticles to the nanofibers is sufficient to retain the nanoparticles on the nanofiber surfaces when water flows through the water filtration membrane. The diameter of the nanofibers is 50-200 nm. The size of the nanoparticles is <40 nm, with a zeta potential of −40 to −45 mV in a dispersion medium. The nanoparticle deep grooves have an average size of approximately 1.2 nm or less.

A water filtration membrane is provided, capable of removing heavy metal ions, filtering out particulates, filtering out bacteria, as well as removing herbicides and volatile organic compounds (VOCs) from water. The membrane is composed of a mat of randomly oriented nanoparticle-coated nanofibers. The nanofibers are covalently bonded to a plurality of substantially uniformly-distributed ceramic nanoparticles embedded in or adhered on the surface of the polymer nanofibers through reactive functional groups. The ceramic nanoparticles have a pattern of deep grooves formed on the nanoparticle surfaces. The bonding of the nanoparticles to the nanofibers is sufficient to retain the nanoparticles on the nanofiber surfaces when water flows through the water filtration membrane. The diameter of the nanofibers is 50-200 nm. The size of the nanoparticles is <40 nm, with a zeta potential of −40 to −45 mV in a dispersion medium. The nanoparticle deep grooves have an average size of approximately 1.2 nm or less.

The present disclosure provides a gas separation membrane module that has high, long-term utility. The present disclosure provides a gas separation membrane module that has: a housing; a gas separation membrane that is arranged inside the housing; and an adhesive part that fixes the gas separation membrane to the housing.

The present disclosure provides a gas separation membrane module that has high, long-term utility. The present disclosure provides a gas separation membrane module that has: a housing; a gas separation membrane that is arranged inside the housing; and an adhesive part that fixes the gas separation membrane to the housing.

Described herein is a method of using hollow fiber filter cartridge. The method includes: providing a hollow fiber filter cartridge inside or outside an environmental cleaning equipment; allowing a wastewater to enter the hollow fiber filter cartridge from an outside of the hollow fiber filter under no water pressure or low water pressure (such as under 30 gw/cm.sup.2); allowing the wastewater to cross a plurality of nanopores of the hollow fiber filter cartridge under no water pressure or low water pressure (such as under 30 gw/cm.sup.2) to produce a clean water; and allowing the environmental cleaning equipment to filter wastewater to produce clean water continuously, thereby improving cleaning efficiency and reducing water consumption.

Described herein is a method of using hollow fiber filter cartridge. The method includes: providing a hollow fiber filter cartridge inside or outside an environmental cleaning equipment; allowing a wastewater to enter the hollow fiber filter cartridge from an outside of the hollow fiber filter under no water pressure or low water pressure (such as under 30 gw/cm.sup.2); allowing the wastewater to cross a plurality of nanopores of the hollow fiber filter cartridge under no water pressure or low water pressure (such as under 30 gw/cm.sup.2) to produce a clean water; and allowing the environmental cleaning equipment to filter wastewater to produce clean water continuously, thereby improving cleaning efficiency and reducing water consumption.

This invention provides a new facilitated transport membrane comprising a relatively hydrophilic, very small pore, nanoporous support membrane, a hydrophilic polymer inside the very small nanopores on the skin layer surface of the support membrane, a thin, nonporous, hydrophilic polymer layer coated on the surface of the support membrane, and metal salts incorporated in the hydrophilic polymer layer coated on the surface of the support membrane and the hydrophilic polymer inside the very small nanopores, a method of making this membrane, and the use of this membrane for olefin/paraffin separations, particularly for C3=/C3 and C2=/C2 separations.