METHOD OF PRODUCING ASYMMETRIC POROUS HOLLOW FIBRE MEMBRANE Russian patent published in 2025 - IPC B01D69/08 D01D5/247 

FIELD: performing operations.

SUBSTANCE: invention relates to membrane separation and more specifically to a method of producing an asymmetric porous hollow fibre membrane which can be used in liquid filtration and/or gas separation processes used in domestic industry. Disclosed is a method of producing a porous asymmetric hollow fibre membrane with an outer skin layer and a coarse structure on the inner surface of the hollow fibre, in which for formation of internal channel liquid is used, which is immiscible with solvent and is not a precipitant for polymer or mixture of polymers that make up moulding solution. Polymer moulding solution composition is prepared from a polymer or a mixture of polymers and a solvent, taken in amounts which provide an average dynamic viscosity of the polymer moulding solution at temperature of 20 °C equal to 5,000-70,000 cP. Moulding solution can additionally contain a pore-forming additive: polyethylene glycol (PEG) or polyvinylpyrrolidone (PVP).

EFFECT: obtaining porous asymmetric hollow fibre membranes with controlled geometry, suitable for use in liquid filtration and/or gas separation processes; absence of a skin layer on the inner surface of the hollow fibre membranes, which leads to a decrease in resistance to mass transfer through the membrane; obtained membranes are characterized by retention coefficient of 99.9% of Blue Dextran calibrant having molecular weight of 70,000 g/mol.

6 cl, 5 dwg, 1 tbl, 14 ex