A composite polyamide reverse osmosis membrane comprising a polyamide layer; where the polyamide layer has a thickness in the range of 50-250 nm, and large open spaces (i.e., free volumes); where the open spaces are defined by a ratio of water flux, J.sub.w, (gfd) divided by the average surface roughness, Ra, (nm) of the polyamide layer; wherein the composite polyamide reverse osmosis membrane has the ratio of J.sub.w/Ra>0.35 gfd/nm when tested at 65 psi, using an aqueous solution containing 250 ppm of NaCl; and a microporous support with a thickness ranging from 100-150 m. The present invention also relates to processes of fabricating the composite polyamide reverse osmosis membrane.

A membrane for microbiological analysis, a production method of a membrane for microbiological analysis, and the use of such membranes for microbiological analysis. Examples include a cellulose membrane for microbiological analysis that is impregnated with a non-ionic surfactant in an amount of from 100 ng/cm2 to 1.0 mg/cm2, with the membrane having a nominal pore size of from 0.20 m to 0.80 m, and a cumulative adsorption pore volume of less than 0.010 cm3/g.

A ceramic membrane includes an alumina (Al.sub.2O.sub.3) layer; and a polyamide nanocomposite layer at least partially covering a surface of the alumina layer. The polyamide nanocomposite layer contains polyamide-functionalized silicon carbide (SiC) nanoparticles having an average particle size of 0.1 to 1 micrometer (m), an amine-functionalized SiC moiety, an acyl aryl moiety, and a piperazine moiety. The amine-functionalized SiC moiety contains a SiC core and an amine functionalized silicon dioxide (SiO.sub.2) shell covering the SiC core. The amine-functionalized SiC moiety is covalently bonded to the piperazine moiety via the acyl aryl moiety; and the amine functionalized SiO.sub.2 shell contains at least one amino group containing structural unit that is covalently bonded to the SiO.sub.2 shell.

Articles are described including a first microfiltration membrane layer having a first major surface and a second major surface disposed opposite the first major surface, and a first silica layer directly attached to the first major surface of the first microfiltration membrane layer. The first silica layer includes a polymeric binder and acid-sintered interconnected silica nanoparticles arranged to form a continuous three-dimensional porous network. A method of making an article is also described, including providing a first microfiltration membrane layer having a first major surface and a second major surface disposed opposite the first major surface, and forming a first silica layer on the first major surface.

Provided is a high permeance nanofiltration membrane with nanoring-like structure and preparation method thereof. The membrane includes a base film and a polyamide layer having nanoring-like structure morphology on its surface. The method includes: (1) formulating a piperazine nanoemulsion containing a surfactant, vegetable oil, piperazine and water; and (2) infiltrating a base film with the piperazine nanoemulsion, and removing excess droplets from the surface of the base film to obtain a treated base film; covering the surface of the treated base film with a solution of trimesoyl chloride in n-hexane to perform interfacial polymerization; and drying the resulting membrane. Introduction of nano-oil droplets into aqueous phase as templates to construct nanoring-like structure morphology on the surface of the polyamide layer significantly increases the specific surface area and free volume of the polyamide layer without losing the salt rejection rate of the membrane, thereby greatly improving its water permeance.

Charged ultrafiltration membranes are synthesized by thermally initiated free-radical polymerization of sodium styrene sulfonate in the pores of an ultrafiltration pre-cursor membrane. The resulting grafted chains of the charged UF membrane provide significant negative charge to maintain nearly complete rejection of proteins at significantly higher flux.

This disclosure relates to the fabrication of high-performance thin film composite (TFC) reverse osmosis (RO) membranes comprising a thin polyamide rejection layer (thickness of 100-200 nanometer), a porous substrate including polysulfone (PSf) layer (thickness of 40-50 micron) cast on polyester nonwoven fabric (thickness of 100 micron). Hydrophilic and antibacterial TFC polyamide RO membranes were developed by incorporating green Lignin and nanostructured silver-based metal organic frameworks (MOFs) into the selective layer. The polyamide layer of TFC RO membranes was fabricated on the porous PSf substrate by interfacial polymerization between aqueous monomer solutions containing MPD, and adequate additives in water and organic monomer solutions containing TMC in the mixture of hexane and co-solvents. The optimized produced RO membranes were provided water flux of 95-100 LMH and sodium chloride (NaCl) salt rejection of 98.5-99.0% during filtration of 2000 ppm NaCl solution at 225 psi pressure, and water flux of 55-60 LMH and sodium chloride (NaCl) salt rejection of 98.6-98.9% during filtration of 35000 ppm NaCl solution at 800 psi pressure. This disclosure also relates to developing a roll-to-roll PSf membrane as a substrate for making TFC RO membranes for water desalination

Certain aspects of the present disclosure are related to systems and methods related to the removal of PFAS molecules. In one aspect, systems comprising a membrane separator and a foam fractionation separator are generally described. In some embodiments, the membrane separator and the foam fractionation separator are fluidically connected such that some or all of a feed comprising PFAS molecules, a surfactant, and a liquid and/or a foam fractionation separator input comprising PFAS molecules and a liquid can be processed by the membrane separator and/or the foam fractionation separator. In some embodiments, at least a portion of the PFAS molecules are removed from the feed and/or the foam fractionation separator input. In some embodiments, the surfactant is present such that some or all of the PFAS molecules are associated with micelles, which may facilitate the removal of the PFAS molecules from the feed and/or the foam fractionation separator input. In some embodiments, the membrane separator rejects PFAS molecules (e.g., associated with micelles) to a greater extent than certain dissolved ions.

A method of producing a silicalite membrane, which includes heating an aqueous solution that includes a dopant precursor and structure-directing template agents to form silicalite seeds incorporated with a dopant, depositing a buffer layer on a ceramic substrate prior to depositing the silicalite seeds on the buffer layer, contacting the ceramic substrate with a solution including the silicalite seeds to form a silicalite layer from the silicalite seeds on the ceramic substrate, and removing the structure-directing template agents to form the silicalite membrane, where the silicalite layer includes silicalite crystals incorporated with a dopant and each of the silicalite crystals has a hollow structure which forms the pores of the silicalite layer. The silicalite membrane includes a ceramic substrate having a buffer layer formed thereon, and a silicalite layer formed on the buffer layer, where the silicalite layer includes silicalite crystals incorporated with a dopant.