Abstract: An electrolytic cell for producing acidic water and alkaline water is disclosed. High-purity acidic water and high-purity alkaline water can be produced in a well balanced proportion from ultrapure water which is supplied in the minimum amount necessary for producing the desired acidic and alkaline waters using the minimum amount of electricity. The electrolytic cell includes an electrolytic acidic-water production unit 3 comprising an anode chamber 6 and an auxiliary cathode chamber 7 separated therefrom by a first ion-exchange membrane 5, and an electrolytic alkaline-water production unit 4 comprising a cathode chamber 10 and an auxiliary anode chamber 9 separated therefrom by a second ion-exchange membrane 8. Separately controllable power supplies are also provided for supplying power to each of the two units. The supply amount of pure water and the amount of electricity used can be fixed according to the desired amounts of acidic and alkaline waters.

Abstract: In an electrolyzer provided according to this invention, the polarity of electrodes is periodically inverted at very short intervals. This has the effect of allowing gases to be generated uniformly all over the surface of each electrode in the form of extremely small bubbles instead of being formed in specific positions in the form of large bubbles as is the case with a conventional electrolyzer in which a direct current is allowed to flow without changing the flow direction. Thus the surfaces of electrodes are prevented from being covered with bubbles, and the flow of liquids along the surfaces of electrodes is not disturbed by the bubbles any more.

Abstract: Electrically regenerable desalting apparatus having the desalting compartment packed with ion exchangers produced by utilizing radiation-initiated graft polymerization, in which said ion exchangers are nonwoven fabrics in the form of a fiber assembly and a cation exchanger and an anion exchanger are disposed in a face-to-face relationship, with a porous material being interposed between the two ion exchangers. Having the ability to reject ions from liquids, the apparatus is particularly suited to the production of pure water in the electrical power generating industries (including the nuclear industry), electronic industry and the pharmaceuticals manufacturing industry, as well as to the desalting of thick fluids encountered in food and chemical manufacturing processes.

Abstract: In a process for an electrochemical treatment of cellulose waste lye, mass transport takes place through a diaphragm or membrane between a cathode chamber and an anode chamber, and optionally through a middle chamber. Cationogenic components are removed from cellulose waste lye containing lignin sulfonates and being located in at least one of the chambers. Lignin sulfonic acids are produced from the waste lye. In an installation for an electrochemical treatment of cellulose waste lye, at least one diaphragm divides at least one reaction vessel into at least one cathode chamber and at least one anode chamber. At least one cathode electrode is disposed in the at least one cathode chamber, and at least one anode electrode is disposed in the at least one anode chamber. The at least one cathode electrode is formed of iron or aluminum and the at least one anode electrode is formed of special steel, in particular V4A steel.

Abstract: A positive electrode made of titanium having its surface electrolytically plated with platinum is disposed at the central position of an electrolytic ionized water producer. A cylindrical anion membrane is annularly arranged spaced from the positive electrode, a cylindrical cation membrane is annularly arranged spaced from the anion membrane, and a cylindrical negative electrode is annularly arranged spaced from the cation membrane. The opposite ends of the positive electrode, the anion membrane, the cation membrane and the negative electrode are watertightly closed with a base cover and a top cover, and a cylindrical first space is formed inside of the anion membrane. An annular second space is defined between the anion membrane and the cation membrane and an annular third space is defined between the cation membrane and the negative electrode. Water is introduced into the second space.

Abstract: An electrodialyzer for desalinating an aqueous solution comprises a plurality of parallel chambers (5, 6, 7, 8) formed alternately of anion exchange membranes (3) and cation exchange membranes (2, 4) arranged in a non-linear flow path the aqueous solution so that the solution passes successively across a surface of each of the membranes. The two end chambers (5, 8) house an anode (9) and a cathode (18) connected to a source of electrical bias (11) and this causes ions to form and to migrate from the flow path into a concentration chamber (6) separated from the flow path by membranes (2, 3) from which the concentrated fluid can be drawn off. A process is also described for desalinating aqueous solutions.

Abstract: Electrodeionization apparatus having a novel polarity reversal protocol designed to provide continuous, high-quality product fluid is described. The protocol involves substitution of a recirculating fluid stream established in an ion-concentrating compartment by a fluid stream having a lower ionic concentration, while maintaining fluid flow through an adjacent ion-depleting compartment. A method and protocol for modifying the ionic makeup of compartment ion exchange material and fluids are also provided. A flow reversal protocol is also provided, during which high-quality fluid product is recovered from the inventive apparatus. The polarity reversal protocol and flow reversal protocol may each be effected separately, or the flow reversal may be introduced into the sequence of the polarity reversal protocol.

Abstract: Electrodialysis ("ED") stacks are disclosed having components selected from the group:a) cation exchange ("CX") membranes and/or CX granules having in at least a surface a predominant amount of sulfonate exchange groups and a minor amount of weakly ionized exchange groups;b) anion exchange ("AX") membranes and/or AX granules having in at least a surface substantially only quaternary ammonium and/or phosphonium exchange groups which upon decomposition leave almost no amine or phosphine groups bound to the membranes or granules;c) AX and/or CX granules which are selective to monovalent ions at currents which are fractions of the limiting current of such granules;d) AX and/or CX membranes and granules, such membranes and granules selective to monovalent ions at currents which are fractions of the limiting current of such membranes and granules;e) ion exchange ("IX") granules in which the concentration of IX groups in the inner regions is a fraction (including zero) of the concentration in the outer regions;f) AX