The present invention relates to a composite semipermeable membrane including: a substrate; a porous support layer disposed on the substrate; and a separation functional layer disposed on the porous support layer, in which the separation functional layer includes: a first layer including a crosslinked aromatic polyamide; and a coating layer existing on the first layer and including an aliphatic polyamide including a fluorine atom, and the composite semipermeable membrane has a proportion of the number of fluorine atoms to the total number of atoms of all elements of 0.5% or more and 8% or less, and has a ratio (N/O ratio) of the number of nitrogen atoms to the number of oxygen atoms of 0.8 or more and 1.3 or less.

A reverse osmosis membrane is disclosed that has a hydrogel disposed on its surface, wherein the hydrogel is formed from a crosslinked polyvinylpyrrolidone or a copolymer of vinyl pyrrolidone. The hydrogel-coated membrane resists fouling by feed water contaminants. The permeate flux rate and salt rejection of the underlying membrane are not negatively affected by the hydrogel coating.

The present invention relates to a fouling resistance reverse osmosis membrane, a method of manufacturing the same, and a fouling resistance reverse osmosis module including the same, and more specifically, to a fouling resistance reverse osmosis membrane, which has excellence in anti-fouling properties against fouling materials such as organic substances, inorganic substances, and the like, antimicrobial performance against microorganisms and the like, a flux, a salt removal rate, and retention of anti-fouling properties and antimicrobial performance, a method of manufacturing the same, and a fouling resistance reverse osmosis module including the same.

A semipermeable arrangement for use in clinical, agricultural, industrial and/or environmental settings. The semipermeable arrangement has a structural arrangement formed from a material such as ePTFE that has an affinity to a lubricating fluid such as perfluorocarbon. The structural arrangement may be infused with a lubricating fluid such that the semipermeable arrangement resists fouling. The semipermeable arrangement is further arranged with barriers to prevent or limit the movement of the lubricating fluid through at least part of the structural arrangement. The semipermeable arrangement further has passageways that are free from the presence of, and/or cannot be infused with, lubricating fluid. The passageways permit the movement of fluids such as air, water and dissolved substances through the structural arrangement. The semipermeable arrangement is thereby both self-cleaning and porous and has a wide range of uses.

A novel membrane is provided in which the permeate flow rate is not prone to decrease even when the membrane is used to process seawater with high salt concentration and high heavy metal ion concentration. This composite semipermeable membrane comprises a porous support layer, a separation function layer arranged on the porous support layer, and a coating layer coating the separation function layer, wherein the separation function layer contains a crosslinked polymer amide which is a condensate of polyfunctional aromatic amine and polyfunctional aromatic acid chloride, and the coating layer contains an aliphatic polymer including a polyether moiety and a carbonic acid polymer moiety.

A method of providing fouling control in a membrane system includes generating a sacrificial protective layer (PL) on a surface of a membrane of the membrane system by coating the membrane with at least one polyelectrolyte layer, removing the PL from the membrane with a saline solution after the PL is fouled, and regenerating a new PL on the surface of the membrane by coating the membrane with at least one polyelectrolyte layer such that foulants present in a feed water accumulate on the PL, rather than on the membrane. The method further comprises one or more of the following: a) the saline solution is being applied with a shear force; b) the pH value of the saline solution is substantially neutral; c) the saline solution is non-toxic; d) the PL is removed without a backwash; e) the PL is not an active filtration layer, wherein a pore size of the PL is greater than a pore size of the membrane; and/or f) the PL is not disposed in pores of the membrane.

By having a coating layer, this composite semipermeable membrane has fouling resistance easily maintainable before and after contact with acid, and enables stable operation over a long period of time. This composite semipermeable membrane comprises a porous support layer, a separation function layer arranged on the porous support layer, and a coating layer arranged on the separation function layer, wherein the separation function layer contains a crosslinked aromatic polyamide which is a polycondensate of polyfunctional aromatic amines and polyfunctional aromatic acid chloride, and the coating layer contains an aliphatic polymer having the structure (I) in the description.

A reverse osmosis membrane is disclosed that has a hydrogel disposed on its surface, wherein the hydrogel is formed from a crosslinked polyvinylpyrrolidone or a copolymer of vinyl pyrrolidone. The hydrogel-coated membrane resists fouling by feed water contaminants. The permeate flux rate and salt rejection of the underlying membrane are not negatively affected by the hydrogel coating.

By having a coating layer, this composite semipermeable membrane has fouling resistance easily maintainable before and after contact with acid, and enables stable operation over a long period of time. This composite semipermeable membrane comprises a porous support layer, a separation function layer arranged on the porous support layer, and a coating layer arranged on the separation function layer, wherein the separation function layer contains a crosslinked aromatic polyamide which is a polycondensate of polyfunctional aromatic amines and polyfunctional aromatic acid chloride, and the coating layer contains an aliphatic polymer having the structure (I) in the description.

A novel membrane is provided in which the permeate flow rate is not prone to decrease even when the membrane is used to process seawater with high salt concentration and high heavy metal ion concentration. This composite semipermeable membrane comprises a porous support layer, a separation function layer arranged on the porous support layer, and a coating layer coating the separation function layer, wherein the separation function layer contains a crosslinked polymer amide which is a condensate of polyfunctional aromatic amine and polyfunctional aromatic acid chloride, and the coating layer contains an aliphatic polymer including a polyether moiety and a carbonic acid polymer moiety.