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.

The present invention relates to a method for producing ceramic gas-separation membranes, which comprises depositing, by means of inkjet printing, water-based inks that form layers of a gas separation membrane. More specifically, the method comprises at least the following steps forming a porous support (i) compatible with a functional separation layer; depositing on the support (i), by means of inkjet printing, at least one functional separation layer (ii) formed by at least two inks, and depositing at least one porous catalytic activation layer (iii) on the functional separation layer (ii); and performing at least one heat treatment, which produces sintering. The functional separation layer (ii) is deposited in a manner to produce a surface with fadings, patterns, or combinations thereof he invention also relates to a gas separation membrane produced using the described method.

A method for preparing a nanofiltration membrane and a nanofiltration membrane prepared therefrom, the method comprising the following steps: dissolving a polymer in a solvent to prepare a polymer solution, and curing the polymer solution on a support material to form a base membrane; sequentially applying a first liquid-phase solution and a second liquid-phase solution on the base membrane to form a nascent membrane; densifying the nascent membrane by using a solution that contains an alkaline substance; processing the densified nascent membrane by using a solution that contains an acidic substance; and obtaining the nanofiltration membrane after post-processing and drying.

Stabilized surfactant-based membranes and methods of manufacture thereof. Membranes comprising a stabilized surfactant mesostructure on a porous support may be used for various separations, including reverse osmosis and forward osmosis. The membranes are stabilized after evaporation of solvents; in some embodiments no removal of the surfactant is required. The surfactant solution may or may not comprise a hydrophilic compound such as an acid or base. The surface of the porous support is preferably modified prior to formation of the stabilized surfactant mesostructure. The membrane is sufficiently stable to be utilized in commercial separations devices such as spiral wound modules. Also a stabilized surfactant mesostructure coating for a porous material and filters made therefrom. The coating can simultaneously improve both the permeability and the filtration characteristics of the porous material.

A method for preparing a high-selectivity lithium-magnesium separation membrane includes: (1) preparing an aqueous phase mixture containing aqueous phase monomer, crown ethers or aza-macrocycles, acid acceptor, surfactant and water; (2) preparing an organic phase mixture containing organic phase monomer, and organic solvent that is incompatible with water; (3) contacting the supporting membrane with the aqueous phase mixture to obtain an aqueous phase monomer-adsorbed supporting membrane; (4) contacting the aqueous phase monomer-adsorbed supporting membrane with an organic phase mixture for an interfacial polymerization reaction; and (5) placing a nascent membrane obtained into a drying oven and heat-treating the membrane to obtain a lithium-magnesium separation membrane. The present method is simple in preparation process, mild in preparation conditions, easy to scale up, and easy to realize industrial production. The prepared high-selectivity lithium-magnesium separation membrane is large in permeation flux, high in lithium-magnesium selectivity and good in long-term operation stability.

Provided is a composition for forming a separation membrane active layer, the composition comprising a compound of the following Chemical Formula 1 and a compound of the following Chemical Formula 2, wherein a percentage (a/b) of a weight (a) of the compound of Chemical Formula 1 to a weight (b) of the compound of Chemical Formula 2 is 30% to 60%, and a pH thereof is 11 to 12.7:

##STR00001## wherein in Chemical Formulae 1 and 2: R1 to R16 are each independently —CRR′— or —NR″—. at least two of R1 to R10 are —NR″—; at least two of R11 to R16 are —NR″—; and R, R′, and R″ are each independently hydrogen or a substituted or unsubstituted alkyl group; a method for producing a separation membrane; a separation membrane; and a water treatment module.

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 μm. The present invention also relates to processes of fabricating the composite polyamide reverse osmosis membrane.

The present invention is directed to surface-treated membranes comprising: (a) a porous substrate; and (b) a coating layer applied to the substrate. The coating layer is formed from a surface treatment composition comprising: (i) a first component comprising an organic solvent; and (ii) a second component comprising a fluorine-containing polymer and a solvent containing at least one C—F bond. The present invention is further drawn to a method of preparing a surface-treated filtration membrane, comprising: (a) contacting a porous substrate with a first component of a surface treatment composition, wherein the first component comprises an organic solvent; (b) subsequently contacting the porous substrate with a second component of the surface treatment composition, wherein the second component comprises a fluorine-containing polymer and a solvent containing at least one C—F bond; and (c) subjecting the porous substrate to a temperature of 25 to 90° C. for 1 to 180 minutes.

The present invention relates to cellulose based papers coated with nitrocellulose as well as to methods for producing such coated papers and methods for using them, especially in lateral flow applications.

The present disclosure relates to carbon nanotube based desalination membranes and methods of manufacturing thereof. The carbon nanotube based desalination membranes may be manufactured by: providing a polymer matrix; providing carbon nanotubes directly contacting the polymer matrix; stirring the carbon nanotubes into the polymer matrix in order to make a carbon nanotube composite solution; and coating a substrate with the carbon nanotube composite solution to form a carbon nanotube desalination membrane. The carbon nanotube based desalination membranes may provide superior flow rate and high levels of salt rejection.