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.

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.

There is provided a semi-permeable membrane comprising: at least two two-dimensional (2D) heterostructure layers of; and a polyelectrolyte layer between each 2D heterostructure layer of the at least two 2D heterostructure layers. There is also provided a method of preparing the membrane comprising: mixing a 2D heterostructure solution and a polyelectrolyte solution to form a mixture; and vacuum filtering the mixture onto a substrate to form the membrane.

There is provided a semi-permeable membrane comprising: at least two two-dimensional (2D) heterostructure layers of; and a polyelectrolyte layer between each 2D heterostructure layer of the at least two 2D heterostructure layers. There is also provided a method of preparing the membrane comprising: mixing a 2D heterostructure solution and a polyelectrolyte solution to form a mixture; and vacuum filtering the mixture onto a substrate to form the membrane.

Described herein are mixed matrix filtration membranes and related, dendrimers, dendrimer particles, compositions, methods and systems and in particular mixed matrix filtration membranes with an embedded dendrimer particles and related compositions, methods, and systems wherein each dendrimer particle comprises at least two dendrimers each having at least two core chemical moieties having a core multiplicity Nc; branch cell units attached to the core chemical moiety or one to another, with the branch cell units attached one to another having a branch cells multiplicity Nb; and a number of surface functional groups Z presented on terminal branch cell units, wherein NcNb.sup.G with G≤3.

Described herein are mixed matrix filtration membranes and related, dendrimers, dendrimer particles, compositions, methods and systems and in particular mixed matrix filtration membranes with an embedded dendrimer particles and related compositions, methods, and systems wherein each dendrimer particle comprises at least two dendrimers each having at least two core chemical moieties having a core multiplicity Nc; branch cell units attached to the core chemical moiety or one to another, with the branch cell units attached one to another having a branch cells multiplicity Nb; and a number of surface functional groups Z presented on terminal branch cell units, wherein NcNb.sup.G with G≤3.

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.

The disclosure relates to processes, related polyacid polymers, and related articles for functionalizing a porous membrane by contacting the membrane with a polyacid polymer at low pH to stably adsorb a polyacid layer on the membrane pore surface, in particular polyacid polymers including repeating units with a pendent metal-binding ligand or star polyacid polymers. The resulting functionalized membrane is characterized by a high density of free acid groups, resulting in a higher specific capacity for its intended application. The process allows functionalization of porous membranes in a very simple, one-step process, for example without a need to derivatize an adsorbed polyacid layer to impart metal-binding ligand functionality thereto. Such functional membranes may find multiple uses, including rapid, selective binding of proteins for their purification or immobilization.

The disclosure relates to processes, related polyacid polymers, and related articles for functionalizing a porous membrane by contacting the membrane with a polyacid polymer at low pH to stably adsorb a polyacid layer on the membrane pore surface, in particular polyacid polymers including repeating units with a pendent metal-binding ligand or star polyacid polymers. The resulting functionalized membrane is characterized by a high density of free acid groups, resulting in a higher specific capacity for its intended application. The process allows functionalization of porous membranes in a very simple, one-step process, for example without a need to derivatize an adsorbed polyacid layer to impart metal-binding ligand functionality thereto. Such functional membranes may find multiple uses, including rapid, selective binding of proteins for their purification or immobilization.