METHOD FOR PRODUCING A POLYSULFONE MEMBRANE FOR FILTRATION OF AQUEOUS MEDIA Russian patent published in 2023 - IPC C08J5/22 B01D67/00 

FIELD: membranes.

SUBSTANCE: producing membranes from polymeric materials, namely polysulfone, for their use in filtering aqueous media. A method for producing a polysulfone membrane for filtration of aqueous media involves dissolving polysulfone polymer in a solvent - N-methylpyrrolidone at a temperature of 45°C to 60°C and constant stirring with a polymer : solvent mass ratio of 1:5, subsequent cooling of the resulting solution to 20°C and its degassing by vacuuming in a vacuum mode from 20 to 5.3 kPa for 30-60 minutes. After that, nanoparticles with a fraction of 100 nm made of crushed compressed microcellulose granules, consisting of fibres with a length of 10 to 30 mcm with a diameter of 2 to 5 mcm, are introduced into the solution with the mass ratio of polymer solution : microcellulose of 25:1. Then the mixture of the polymer solution with microcellulose is dry-moulded to obtain a matrix, which is then degassed by vacuuming in a vacuum of 20 to 5.3 kPa and dried at a temperature of 120°C for 3 hours. To obtain the finished membrane, the matrix is treated with a 40-60% solution of sulfuric acid for 30 minutes to 180 minutes, washed in water, and dried at a temperature of 120°C for no more than 60 min. The structure of membranes obtained by SEM and TEM methods is shown in Fig. 1-4.

EFFECT: expansion of the range of polysulfone membranes with the specified characteristics and simplification of the moulding process by eliminating equipment changeover.

2 cl, 4 dwg