Methods and systems for producing and using multi-layer composite co-polyimide membranes, one method for producing including preparing a microporous or mesoporous membrane support material for coating; applying a sealing layer to the membrane support material to prevent intrusion into the membrane support material of co-polyimide polymer; applying a first permselective co-polyimide layer atop and in contact with the sealing layer; and applying a second permselective co-polyimide layer atop and in contact with the first permselective co-polyimide layer.

A method for producing a crystalline film comprising zeolite and/or zeolite-like crystals on a porous substrate is described. The method has the steps of: providing a porous support; modifying at least a surface of the top-layer of said porous support by treatment with a composition having one or more cationic polymer(s); rendering at least the outer surface of said porous support hydrophobic by treatment with a composition having one or more hydrophobic agent(s); subjecting said treated porous support to a composition having zeolite and/or zeolite-like crystals thereby depositing and attaching zeolite and/or zeolite-like crystals on said treated porous support, and growing a crystalline film of zeolite and/or zeolite-like crystals on said treated porous support and calcination. Crystalline films find use in a variety of fields such as in the production of membranes, catalysts etc.

Provided is a nanofiltration (NF) or reverse osmosis (RO) membrane made of a hard carbon film that has oil resistance and can efficiently separate not only ions in water but also dye molecules present in an organic solvent, a filtering filter, a two-layer-bonded-type filtering filter, and methods for manufacturing the same, using a nanofiltration (NF) or reverse osmosis (RO) membrane (10) made of a hard carbon film characterized by being made of a hard carbon film, having a thickness (t.sub.10) of from 5 nm to 300 nm, and having a maximum pore diameter of less than 0.86 nm.

A gas separation membrane, characterized by having a porous support and a polyamine layer formed on the porous support, the number-average molecular weight of the polyamine constituting a part of the polyamine being 100,000-500,000.

A method for coating hollow fiber membranes is disclosed. The method includes preparing a continuous circulating circuit, which includes a membrane contactor module, two liquid reservoirs containing a solvent, two pipeline paths, and at least one injector. The membrane module include a plurality of hollow fiber membranes with an inside area and an outside area, and a housing, where the plurality of hollow fiber membranes are extended inside the housing. The method further include forming a plurality of wetted hollow fiber membranes with the solvent by circulating the solvent through the continuous circulating circuit, filling at least one of the two liquid reservoirs with a coating solution, forming a coating layer on a surface of at least one of the inside area or the outside area of the plurality of wetted hollow fiber membranes by circulating the coating solution through the continuous circulating circuit, and forming a uniform coating layer by injecting the coating solution by the injector for intrusion of the coating solution through the coating layer.

A gas separation membrane, characterized by having a porous support and a polyamine layer formed on the porous support, the number-average molecular weight of the polyamine constituting a part of the polyamine being 100,000-500,000.

A method for coating hollow fiber membranes is disclosed. The method includes preparing a continuous circulating circuit, which includes a membrane contactor module, two liquid reservoirs containing a solvent, two pipeline paths, and at least one injector. The membrane module include a plurality of hollow fiber membranes with an inside area and an outside area, and a housing, where the plurality of hollow fiber membranes are extended inside the housing. The method further include forming a plurality of wetted hollow fiber membranes with the solvent by circulating the solvent through the continuous circulating circuit, filling at least one of the two liquid reservoirs with a coating solution, forming a coating layer on a surface of at least one of the inside area or the outside area of the plurality of wetted hollow fiber membranes by circulating the coating solution through the continuous circulating circuit, and forming a uniform coating layer by injecting the coating solution by the injector for intrusion of the coating solution through the coating layer.

The present invention discloses stable composite membranes comprising a porous support having one or more thin selective layers coated on a top surface thereof, whereas at least one of said thin selective layers comprises a crosslinked fluorinated silicone polymer, and further wherein the total thickness of said one or more thin selective layers ranges between 0.1 to 10 microns. The use of these membranes in the process of olive oil wastewater treatment and the valorization of polyphenol-rich by-products, are also disclosed.

The present invention relates to a process for the preparation of a supported Carbon Membranes (CMS). The present invention also relates to a process for the separation of a gas from a gas mixture and to the use of use of a supported CMs as a membrane reactor or in a membrane reactor.

An object of the present invention is to provide a composite semipermeable membrane which has practical water permeability and high alkali resistance. The composite semipermeable membrane of the present invention includes: a supporting membrane including a substrate and a porous supporting layer; and a separation functional layer disposed on the porous supporting layer of the supporting membrane, in which the separation functional layer includes a crosslinked fully aromatic polyamide, and when a carboxyl group/amide group molar ratio of the separation functional layer measured by a .sup.13C solid NMR spectroscopy is expressed by x, x is 0.54 or less.