Disclosed herein are nanoporous membranes for separating a target substance from a non-target substance in a fluid medium and methods of making and use thereof. The nanoporous membranes comprise a 2D material permeated by a first and second population of pores; wherein the average pore diameter of the first population of pores is greater than or equal to the van der Waals diameter of water and less than the average size of the non-target substance in the fluid medium; wherein the average pore diameter of the second population of pores is greater than or equal to the average size of the non-target substance in the fluid medium; and wherein substantially all of the second population of pores are substantially blocked by a polymer via size-selective interfacial polymerization; such that the nanoporous membrane allows for transport of the target substance through the nanoporous membrane via the first population of pores.

Disclosed herein are nanoporous membranes for separating a target substance from a non-target substance in a fluid medium and methods of making and use thereof. The nanoporous membranes comprise a 2D material permeated by a first and second population of pores; wherein the average pore diameter of the first population of pores is greater than or equal to the van der Waals diameter of water and less than the average size of the non-target substance in the fluid medium; wherein the average pore diameter of the second population of pores is greater than or equal to the average size of the non-target substance in the fluid medium; and wherein substantially all of the second population of pores are substantially blocked by a polymer via size-selective interfacial polymerization; such that the nanoporous membrane allows for transport of the target substance through the nanoporous membrane via the first population of pores.

The present specification provides a composition comprising a material of Chemical Formula 1: ##STR00001##
having a molecular weight of 500,000 to 700,000 where R1 and R2 are the same as or different from each other, and each independently is hydrogen, deuterium, or an alkyl group, and n is from 10,000 to 20,000, for forming a reverse osmosis membrane protective layer, a method for preparing a reverse osmosis membrane using the same, a reverse osmosis membrane and a water-treatment module.

The present specification provides a composition comprising a material of Chemical Formula 1: ##STR00001##
having a molecular weight of 500,000 to 700,000 where R1 and R2 are the same as or different from each other, and each independently is hydrogen, deuterium, or an alkyl group, and n is from 10,000 to 20,000, for forming a reverse osmosis membrane protective layer, a method for preparing a reverse osmosis membrane using the same, a reverse osmosis membrane and a water-treatment module.

The present invention relates to ultrathin polymer nanofilm and its composite membrane, its method of preparation. Composite membranes are produced via interfacial polymerization of diamine (or polyamine) monomer (or polymer) and trimesoyl chloride. After IP, post-treatment of washing nascent nanofilm with sufficient volume of solvent and drying at room temperature for 10-30 s followed by annealing at 70-100° C. for 1-10 min is developed. This washing step removes remaining TMC in organic phase and stops further growth of polyamide nanofilm. Ultrathin nanofilm composite membrane gives high water permeance (up to 61.3 Lm.sup.−2h.sup.−1bar.sup.−1) with high rejection of Na.sub.2SO.sub.4 (up to 99.3%) by maintaining relatively low rejection of MgCl.sub.2 (up to 27.7%) and NaCl (up to 11.9%) tested under 5 bar pressure at 25 (±1) ° C. with 2 g/L feed solution.

The present invention relates to ultrathin polymer nanofilm and its composite membrane, its method of preparation. Composite membranes are produced via interfacial polymerization of diamine (or polyamine) monomer (or polymer) and trimesoyl chloride. After IP, post-treatment of washing nascent nanofilm with sufficient volume of solvent and drying at room temperature for 10-30 s followed by annealing at 70-100° C. for 1-10 min is developed. This washing step removes remaining TMC in organic phase and stops further growth of polyamide nanofilm. Ultrathin nanofilm composite membrane gives high water permeance (up to 61.3 Lm.sup.−2h.sup.−1bar.sup.−1) with high rejection of Na.sub.2SO.sub.4 (up to 99.3%) by maintaining relatively low rejection of MgCl.sub.2 (up to 27.7%) and NaCl (up to 11.9%) tested under 5 bar pressure at 25 (±1) ° C. with 2 g/L feed solution.

The present invention aims to improve the separation selectivity for light gases such as hydrogen and helium. The gas separation membrane according to the present invention includes a porous support layer and a separation functional layer containing a cross-linked polyamide and laid on the porous support layer, wherein: the separation functional layer has a protuberance structure containing a plurality of protrusions and recesses; randomly selected 20 of the protrusions on the surface of the separation functional layer indented under a load of 3 nN and observed in pure water at 25° C. by atomic force microscopy give an average deformation of 5.0 nm or more and 10.0 nm or less; and they give a standard deviation of the deformation of 5.0 nm or less.

The present invention aims to improve the separation selectivity for light gases such as hydrogen and helium. The gas separation membrane according to the present invention includes a porous support layer and a separation functional layer containing a cross-linked polyamide and laid on the porous support layer, wherein: the separation functional layer has a protuberance structure containing a plurality of protrusions and recesses; randomly selected 20 of the protrusions on the surface of the separation functional layer indented under a load of 3 nN and observed in pure water at 25° C. by atomic force microscopy give an average deformation of 5.0 nm or more and 10.0 nm or less; and they give a standard deviation of the deformation of 5.0 nm or less.

A high-performance thin-film composite polyamide membrane upcycled from a substrate fouled with a biopolymer and a preparation method thereof are provided. The method includes fouling the substrate preferably with the biopolymer to obtain a composite of the substrate and a biopolymer foulant layer; then immersing the composite into a first solution formed by dissolving a polyamine monomer in water, followed by taking the composite out of the first solution and removing excess droplets from a surface of the composite; then immersing the composite treated in the previous step into a second solution formed by dissolving an acyl chloride monomer in n-hexane for interfacial polymerization to form a rejection layer on the surface of the composite; and after completion of the reaction, taking the composite out of the second solution, followed by drying and heat treatment, to obtain the target polyamide membrane.

A high-performance thin-film composite polyamide membrane upcycled from a substrate fouled with a biopolymer and a preparation method thereof are provided. The method includes fouling the substrate preferably with the biopolymer to obtain a composite of the substrate and a biopolymer foulant layer; then immersing the composite into a first solution formed by dissolving a polyamine monomer in water, followed by taking the composite out of the first solution and removing excess droplets from a surface of the composite; then immersing the composite treated in the previous step into a second solution formed by dissolving an acyl chloride monomer in n-hexane for interfacial polymerization to form a rejection layer on the surface of the composite; and after completion of the reaction, taking the composite out of the second solution, followed by drying and heat treatment, to obtain the target polyamide membrane.