Abstract: A composite ion exchanger with ion exchange groups uniformly dispersed therein, comprising a porous polymer having a continuous pore structure, which comprises interconnected macropores and mesopores existing on the walls of the interconnected macropores, having a total pore volume of 1 to 50 ml/g, and a dense layer covering at least one surface of the porous polymer and integrally formed with the porous polymer. The structure provides a body integrally formed from a material functioning as an ion exchange membrane and a material functioning as an ion exchanger and allows the material functioning as an ion exchanger to have an extremely large pore volume and specific surface area. Electric power saving is possible if the product is used as an electrodeionization module for an electrodeionization water purification device.

Abstract: A porous ion exchanger includes an open cell structure including interconnected macropores and mesopores whose average diameter is in a range of 1 to 1000 &mgr;m existing on walls of the macropores. Moreover, a total pore volume is in a range of 1 to 50 ml/g, ion exchange groups are uniformly distributed, and an ion exchange capacity is not less than 0.5 mg equivalent/g of dry porous ion exchanger. The porous ion exchanger can be used as an ion exchanger filled into a deionization module of an electrodeionization water purification device, solid acid catalyst, adsorbent, and filler for chromatography.

Abstract: A cation exchange membrane (11) and an anion exchange membrane (12) are alternately arranged between an anode (20) and a cathode (19). A desalination chamber (14) and a concentrating chamber (15) are alternately formed between both the exchange membranes (11), (12). Then, the desalination chamber (14) is formed to hold a channel through which liquid flows from one to the other side of the desalination chamber, and allow the cation exchange membrane (11) to contact the anion exchange membrane (12). There is thus obtained an electrodeionization water producing apparatus which maintains a deionizing efficiency as in a conventional case, has a simple structure, is easy to manufacture, and has a high degree of freedom of apparatus configuration.

Abstract: A reverse osmosis treatment of feed water containing at least silica and hardness ions for separating the feed water into permeate water and concentrate is effected while maintaining the pH of the concentrate at a level of at most 6. According to the foregoing process, silica can be prevented from precipitating, and a high recovery of permeate water can be secured.

Abstract: A hemopurification apparatus includes a porous membrane permeable to gas but impermeable to liquid and dividing a container into two mutually-isolated compartments. The apparatus is adapted to remove water from blood by causing the blood to flow through one of the compartments and a fluid, the water vapor pressure of which is lower than that of the blood, to flow through the other compartment, whereby a portion of the water in the blood is allowed to pass as water vapor through the porous membrane.