Filter membrane and device

A porous hollow fiber membrane comprising i) polyethersulfone;

• ii) polyvinylpyrrolidone;
• and iii) a polymer bearing ammonium groups, wherein the polymer bearing ammonium groups is selected from the group consisting of polyalkyleneoxides bearing ammonium groups obtained by reaction of a tertiary amine with a copolymer of ethylene oxide and epichlorohydrin,
• wherein the polymer bearing ammonium groups corresponds to the formula
• wherein
• R1, R2, and R3 are individually selected from H, alkyl, and benzyl;
• and
• X− is Cl−;
• with
• 0≤x≤0.9;
• 0≤y≤0.8;
• 0≤z≤0.9;
• and x+y+z=1,
• polyvinylpyridines bearing ammonium groups obtained by a reaction of a polyvinylpyridine with an alkylating agent selected from the group consisting of dimethyl sulfate and diethyl sulfate, and copolymers of vinylpyridine and styrene bearing ammonium groups obtained by reaction of a copolymer of vinylpyridine and styrene with an alkylating agent and corresponding to the formula
• wherein
• R1, R2, R3, and R4 are individually selected from H, alkyl, and benzyl;
• R5 is selected from alkyl and benzyl;
• and
• X− is selected from Cl−, Br−, and SO42−;
• with
• 0≤x<1;
• 0<y≤0.5;
• 0<z≤0.5;
• and x+y+z=1,
• wherein the membrane has a sponge-like structure, and
• wherein the membrane comprises a mean flow pore size, determined by capillary flow porometry, which is larger than about 0.2 μm.