COMPOSITE ASYMMETRIC POLYMER PERVAPORATION MEMBRANE Russian patent published in 2020 - IPC B01D71/64 B82B3/00 

FIELD: chemistry.

SUBSTANCE: invention relates to the chemistry of high-molecular compounds. Membrane consists of a porous working selective diffusion layer formed from a polyimide with a link formula:

m:n = 0–2, or a salt form thereof with triethylammonium ions, alkali and/or alkali-earth metals, or a cross-linked aromatic diamine of a nanoporous form underlayer and microporous substrate, together comprising an ultrafiltration membrane substrate made from the same polyimide, or other polymer used to make ultrafiltration membranes, thickness of the working layer is 0.01–5 mcm, thickness of sublayer is 1–30 mcm, total thickness of membrane is 120–300 mcm, average pore diameter of sublayer is 3–60 nm, average diameter of the pores of substrate is 5–8 mcm.

EFFECT: technical result is providing a membrane which can be used to separate a mixture of liquid substances having similar boiling points, forming azeotropes, undergoing chemical conversions when heated to temperatures close to boiling points; concentrating aqueous solutions of organic substances, primarily aliphatic alcohols, in a wide range of concentrations, desalting solutions in the technology of producing medicines, alcoholic beverages and biofuel.

3 cl, 2 tbl, 18 ex