The present invention relates to a comprehensive evaluation method for the performance of contaminated flat membranes, which relates to the field of sewage and waste resource technology. The present invention firstly analyzed the composition of the surface elements of the contaminated membrane by EDX to determine the type of membrane contamination, and then designed different cleaning schemes for organic or inorganic pollution to obtain a sample membrane. When the tensile strength of the contaminated membrane decreased more than 50% than that of the control membrane, it is a waste membrane; when the tensile strength decreased less than 50% and the membrane flux reduced more than 30%, it is a waste membrane; when tensile strength decreased less than 50%, membrane flux reduced less than 30% and the carbon footprint was more than 188 g, it is a waste membrane; otherwise was a old membrane. The comprehensive evaluation method of the present invention can quantitatively, quickly and comprehensively define the difference between the old membrane and the waste membrane, and provides the basis for the selection of the contaminated membrane and the process of the regeneration and reuse.

The present invention relates to a comprehensive evaluation method for the performance of contaminated flat membranes, which relates to the field of sewage and waste resource technology. The present invention firstly analyzed the composition of the surface elements of the contaminated membrane by EDX to determine the type of membrane contamination, and then designed different cleaning schemes for organic or inorganic pollution to obtain a sample membrane. When the tensile strength of the contaminated membrane decreased more than 50% than that of the control membrane, it is a waste membrane; when the tensile strength decreased less than 50% and the membrane flux reduced more than 30%, it is a waste membrane; when tensile strength decreased less than 50%, membrane flux reduced less than 30% and the carbon footprint was more than 188 g, it is a waste membrane; otherwise was a old membrane. The comprehensive evaluation method of the present invention can quantitatively, quickly and comprehensively define the difference between the old membrane and the waste membrane, and provides the basis for the selection of the contaminated membrane and the process of the regeneration and reuse.

A method for preparing a durably hydrophilic and uniform-pore ultrafiltration membrane is disclosed herein. Chemical reactions between the functional groups and the active bonds of the molecular chains in the membrane materials are initiated perform the grafting of hydrophilic chains on the polymer chains under conventional dissolution conditions of the polymer membrane material (dissolution with synchronized hydrophilization), so as to realize durable hydrophilization of the membrane materials. The resulting hydrophilized polymer solution (a nascent-state membrane) is introduced into a coagulation bath to initiate a crosslinking reaction among the hydrophilic chains. The resulting crosslinking serves to synergistically regulate subsequent phase separation and membrane formation (phase separation under synergistic crosslinking).

A method for preparing a durably hydrophilic and uniform-pore ultrafiltration membrane is disclosed herein. Chemical reactions between the functional groups and the active bonds of the molecular chains in the membrane materials are initiated perform the grafting of hydrophilic chains on the polymer chains under conventional dissolution conditions of the polymer membrane material (dissolution with synchronized hydrophilization), so as to realize durable hydrophilization of the membrane materials. The resulting hydrophilized polymer solution (a nascent-state membrane) is introduced into a coagulation bath to initiate a crosslinking reaction among the hydrophilic chains. The resulting crosslinking serves to synergistically regulate subsequent phase separation and membrane formation (phase separation under synergistic crosslinking).

A plasma activated water production system includes a plasma reactor and a membrane concentrator. The plasma reactor includes an internal cavity, at least one electrically-conductive inlet capillary and outlet capillary. A mixing chamber has a feed gas inlet, a liquid inlet, and a mixed gas and liquid outlet. A power source is provided. The plasma reactor propagates a plasma discharge between the inlet capillary and the outlet capillary. A membrane concentrator includes a water flow channel with a water inlet and a water outlet, a dry gas inlet and a humidified gas outlet. An ion selective membrane is provided, and water will pass through the membrane into the dry gas, and the water leaving the membrane concentrator will have increased concentrations of nitrates, nitrites and hydrogen peroxide. An electrodialysis embodiment and a method of generating plasma activated with increased concentration of nitrates, nitrites and hydrogen peroxide are also disclosed.

A plasma activated water production system includes a plasma reactor and a membrane concentrator. The plasma reactor includes an internal cavity, at least one electrically-conductive inlet capillary and outlet capillary. A mixing chamber has a feed gas inlet, a liquid inlet, and a mixed gas and liquid outlet. A power source is provided. The plasma reactor propagates a plasma discharge between the inlet capillary and the outlet capillary. A membrane concentrator includes a water flow channel with a water inlet and a water outlet, a dry gas inlet and a humidified gas outlet. An ion selective membrane is provided, and water will pass through the membrane into the dry gas, and the water leaving the membrane concentrator will have increased concentrations of nitrates, nitrites and hydrogen peroxide. An electrodialysis embodiment and a method of generating plasma activated with increased concentration of nitrates, nitrites and hydrogen peroxide are also disclosed.

A bipolar membrane in which a cation-exchange membrane and an anion-exchange membrane are joined to each other, wherein a leakage ratio of gluconic acid at 60° C. is not more than 1.0%, and the cation-exchange membrane is supported by a polyolefin reinforcing member and, further, contains a polyvinyl chloride.

The present disclosure provides the synthesis of an imidazolium-based functional ionic liquid copolymer (PMMA-b-PIL-R*) and a preparation method of an alloy ultra-filtration membrane. Firstly, PMMA-b-PIL-R* is prepared from methyl methacrylate (MMA) and polymerizable imidazolium-based functional ionic liquid (IL-R*) containing double bonding as the reactive monomers through sequential radical polymerization. With the use of a non-solvent induced phase separation method, PMMA-b-PIL-R* is introduced into the body of a polymeric membrane material, so as to prepare an alloy ultra-filtration membrane. A hydrogen-bond interaction is generated between the carbonyl in the molecular chain of PMMA-b-PIL-R* and the H . . . C—Cl structure in the molecular chain of the polymeric membrane material, which enhances the compatibility between the molecular chains of PMMA-b-PIL-R* and the polymeric membrane material, so that it can be stable in the ultra-filtration membrane; the imidazole groups and functional groups in the molecular chain of PMMA-b-PIL-R* can provide a good hydrophilicity.

The present disclosure provides the synthesis of an imidazolium-based functional ionic liquid copolymer (PMMA-b-PIL-R*) and a preparation method of an alloy ultra-filtration membrane. Firstly, PMMA-b-PIL-R* is prepared from methyl methacrylate (MMA) and polymerizable imidazolium-based functional ionic liquid (IL-R*) containing double bonding as the reactive monomers through sequential radical polymerization. With the use of a non-solvent induced phase separation method, PMMA-b-PIL-R* is introduced into the body of a polymeric membrane material, so as to prepare an alloy ultra-filtration membrane. A hydrogen-bond interaction is generated between the carbonyl in the molecular chain of PMMA-b-PIL-R* and the H . . . C—Cl structure in the molecular chain of the polymeric membrane material, which enhances the compatibility between the molecular chains of PMMA-b-PIL-R* and the polymeric membrane material, so that it can be stable in the ultra-filtration membrane; the imidazole groups and functional groups in the molecular chain of PMMA-b-PIL-R* can provide a good hydrophilicity.

A cation-exchange membrane using a polyolefin-based substrate with reduced swelling of an ion-exchange resin and a low electrical resistance is provided. The cation-exchange membrane of the present invention includes a substrate made of polyolefin-based woven fabric, and a sulfonic acid group-containing cation-exchange resin. A portion of the cation-exchange membrane other than the substrate has 23 mass % or more to 35 mass % or less of polyvinyl chloride.