METHOD OF PRODUCING MEMBRANES FOR ULTRAFILTRATION OF AQUEOUS MEDIA Russian patent published in 2019 - IPC B82Y40/00 B01D71/08 B01D61/14 

FIELD: chemistry.

SUBSTANCE: invention relates to membrane technology and can be used for purification and separation of water and aqueous solutions. Method of producing membranes for ultrafiltration of aqueous media, comprising forming a porous polymer membrane by using a double-channel spinneret with concentric arrangement of channels by passing a precipitator through a central channel of the spinner while simultaneously feeding a molding solution through an annular channel containing 10–24 wt. % polymer, from 0 to 40 wt. % of a blowing agent and from 50 to 90 wt. % of a solvent to form a hollow polymer tube which, as molded, is fed into a vessel with a precipitation agent to form a polymer hollow fibre which is stretched to achieve a predetermined post-filter extract, after which the fibre is placed in an aqueous medium and hydrophilising the obtained hollow polymer fibre by feeding into the polymer fibre cavity a dispersion of nanosized particles of cellulose in the form of nanofibrillar cellulose fibres with fibre diameter of less than 100 nm and fibre length of less than 10 mcm or in form of crystals of nanocrystalline cellulose with crystal diameter of less than 10 nm and crystal length of less than 500 nm to form hydrophilic layer in membrane cavity during filtration of dispersion of nanosized particles of cellulose through wall of hollow fibre.

EFFECT: technical result is correction of membranes production mode due to regulation of thinning wall of hollow fibre during membranes moulding, as a result of which it is possible to form selective hydrophilic layer on membrane working surface with preservation of high efficiency.

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