Abstract: Described is a system and corresponding method for remediating liquid waste streams. The system includes an electro-oxidation (EO) chamber, an electro-deposition (ED) chamber, and an electro-adsorption (EA) chamber. In the method, a waste stream is subjected to electro-oxidation, followed by electro-deposition and/or electro-adsorption. The method removes both organic and inorganic pollutants, as well as metals present as free ions or bound into organic or inorganic complexes.

Abstract: An efficient method and system for the electrochemical treatment of waste water comprising organic and/or inorganic pollutants is disclosed. The system comprises at least first and second solid polymer electrolyte electrolytic cell stacks in which each cell comprises a solid polymer, proton exchange membrane electrolyte operating without catholyte or other supporting electrolyte. The first and second stacks differ either in construction or operating condition. The cell stack design and operating conditions chosen provide for significantly greater operating efficiency.

Abstract: The apparatus for water treatment using in-situ activation of a manganese dioxide catalyst includes: a reaction bath configured to give a space where aqueous organic contaminants are removed by means of reaction with permanganate (MnO4?) generated by electrochemical oxidation of manganese oxide (MnO2); a plurality of manganese dioxide catalysts provided at the reaction bath and electrochemically oxidized into permanganate (MnO4?) by a voltage applied thereto; and a power supply device configured to apply power to the manganese dioxide catalyst so that the manganese dioxide (MnO2) is electrochemically oxidized into permanganate (MnO4?).

Abstract: A water conditioner that utilizes ionic flow and selective ionic filtering to control water hardness and/or pH. In some embodiments, the water conditioner includes one or more conditioning cells each having electrodes and a cathode side and an anode side separated by an ion-selective filter. The ion-selective filter is design/configured/selected to pass alkaline earth metal cations and block corresponding carbonate anions. When the electrodes are energized and water is present on the cathode and anode sides of the filter membrane, the alkaline earth metal cations pass from the anode side to the cathode side through the membrane, while the membrane blocks carbonate ions on the cathode side from passing to the anode side. In this manner, alkaline earth metal cations, and water hardness, can be reduced in the anode flow.

Abstract: Contaminants are filtered from a fluid flow stream and the filter is regenerated by a process including steps of: providing a filter material comprising both carbon and potassium iodide; passing a contaminated fluid stream in contact with the filter material; adsorbing contaminants from the fluid stream onto surfaces in the filter material; passing an electric current through the filter material with adsorbed contaminant thereon; disassociating contaminant from the surfaces of the filter material; and removing disassociated contaminant from the filter material by carrying away the disassociated contaminant in a fluid flow mass. Separately, a stable, active iodine solution is also provided for numerous deodorizing and disinfecting applications.

Abstract: A coagulation generating system that combines the advantages of conventional and electrocoagulation. In the coagulation generating system electro-coagulation is performed on an input (e.g., salt/brine) solution to generate a concentrated coagulant solution, which is then added to the source water in the same way as a standard stored chemical coagulant.

Abstract: The invention relates to methods and devices for the decontamination of fluid, particularly the removal of heavy metals and/or arsenic and/or their compounds from water, by means of electrolysis, wherein the water to be purified subjected to electrodes of different polarities. The invention can include means for control of the pH of the fluid. The invention can also include control systems that allow self-cleaning of electrodes, self-cleaning of filters, and automatic monitoring of maintenance conditions.

Abstract: The present invention provides for a system for removing arsenic from an arsenic contaminated aqueous solution, and its use thereof. The system comprises an anode comprising iron and a cathode comprising iron or an electricity conducting metal that is electropositive relative to iron in contact with the arsenic contaminated aqueous solution. The system is used by running an electric current through the water via the anode and cathode to cause the formation of iron (hydr)oxide from the iron of the anode which then forms an insoluble arsenic-iron (hydr)oxide complex which can be separated from the aqueous solution.

Abstract: A volume-porous electrode is provided which increases effectiveness and production of electrochemical processes. The electrode is formed of a carbon, graphitic cotton wool, or from carbon composites configured to permit fluid flow through a volume of the electrode in three orthogonal directions. The electrode conducts an electrical charge directly from a power source, and also includes a conductive band connected to a surface of the electrode volume, whereby a high charge density is applied uniformly across the electrode volume. Apparatus and methods which employ the volume-porous electrode are disclosed for removal of metals from liquid solutions using electroextraction and electro-coagulation techniques, and for electrochemical modification of the pH level of a liquid.

Abstract: An apparatus and method for the electrolytic and electrodialytic removal of metal ions from wastewater in a single cell. A battery of cells, each of which consists of a cathode, anode, anion exchange membrane and cation exchange membrane, is used. The battery of cells may be used in both batch and continuous processes, and is capable of reducing metal ion concentration from thousand ppm to few ppm. It can be used to concentrate dilute acids as a by-product.

Abstract: The invention relates to methods and devices for the decontamination of fluid, particularly the removal of heavy metals and/or arsenic and/or their compounds from water, by means of electrolysis, wherein the water to be purified subjected to electrodes of different polarities. The invention can include means for control of the pH of the fluid. The invention can also include control systems that allow self-cleaning of electrodes, self-cleaning of filters, and automatic monitoring of maintenance conditions.

Abstract: The invention disclosed relates to an electrochemical process for decreasing high levels of organic contaminants in metal plating baths. The process involves breaking down the organic contaminants in an electrochemical cell by electrochemical oxidation. The electrochemical cell includes an anode comprising an active material which is stable at low (acid) pH and at the high electrical potential required to break down the organic contaminants by oxidation. Typical examples of such anodes include a valve metal substrate coated with doped tin dioxide, lead dioxide, or platinum-based materials, the latter in some instances being coated on a high surface area valve metal substrate.

Abstract: A method and apparatus for removing a group of species of metal ions from an aqueous solution to be purified which involves the steps for each species in succession of adjusting the pH of the aqueous solution to a value where hydroxide precipitates of said species in its highest valency state are insoluble, then passing the aqueous solution through an ion state modification cell to raise the valence of the respective species to its highest valency state thus causing the ion specie to form the insoluble hydroxide, then removing the precipitated hydroxide from the aqueous solution by appropriate steps of settling and press filtering. A magnetic field is imposed between the electrodes which improves the efficiency of the ion state modification step.

Abstract: A method and apparatus concentrates, collects and removes heavy metals, other cations, and anions from media permitting generation of electrical fields. The heavy metals and other cations are electrochemically concentrated and precipitated for rapid removal from the aqueous media. The media, which may be aqueous, soils or wastes, is filtered and passed through a cation or anion exchange resin beds. Metals or anions are captured and held in the resin beds. Current is then applied through the resin beds using opposing electrodes of opposite polarity. In the metal removal units, heavy metals and other cations are concentrated around the negative electrode and lifted to a top of the electrode chamber using hydrogen gas lift. The concentrated solution of heavy metals and cations are removed from the chamber above the negative electrode and are circulated to provide additional time for growth and precipitation.

Abstract: A method and apparatus concentrates, collects and removes heavy metals, other cations, and anions from media permitting generation of electrical fields. The heavy metals and other cations are electrochemically concentrated and precipitated for rapid removal from the aqueous media. The media, which may be aqueous, soils or wastes, is filtered and passed through a cation or anion exchange resin beds. Metals or anions are captured and held in the resin beds. Current is then applied through the resin beds using opposing electrodes of opposite polarity. In the metal removal units, heavy metals and other cations are concentrated around the negative electrode and lifted to a top of the electrode chamber using hydrogen gas lift. The concentrated solution of heavy metals and cations are removed from the chamber above the negative electrode and are circulated to provide additional time for growth and precipitation.

Abstract: A method for electrochemically purifying solutions with a pH higher than 14 to reduce metal impurities to the level of traces. The method comprises processing the solutions in an electrolytic cell in which the cathode has a fibrous web produced from a mixture of fibres including at least one fraction consisting of electrically conductive fibres and a binder selected from fluoropolymers, said fibrous web being deposited on an electrically conductive porous support. Said cathode may also be combined with a diaphragm or a membrane. A cathode having a fibrous web produced from a mixture of carbon fibres, cellulose compounds, and a cationic polymer such as cationic starch is also disclosed.

Abstract: An increasing problem with the pulping chemical recovery system, is the presence of chloride and potassium in the recovery boiler. Chloride and potassium increase inter alia the stickiness of carryover deposits and dust particles to the recovery boiler tubes, which accelerate fouling, corrosion and plugging of the recovery boiler. As the environmental legislation becomes more stringent, the degree of system closure increases. The present invention relates to a process by which the collected precipitator dust is leached, at a temperature exceeding 50.degree. C., for a residence time sufficient to get a chloride and potassium enriched leach solution and to remove at least a part of the content of metal ions in a solid phase. Said leach solution is electrochemically treated, preferably in an electrodialysis cell, in order to remove at least a part of the chloride and potassium therein. By the present process, the problem of sticky deposits in the recovery boiler can be substantially reduced.

Abstract: Although a chelating agent solution having radioactive contaminants is solidified by mixing with cement and then stored, a vast storage place is required for storing an enormous amount of chelating agent solution. When such a chelating agent solution is treated with an ion-exchange resin, a large amount of ion-exchange resin is required, and a large amount of ion-exchange resin having radioactive contaminants is produced. The present invention thus provides a method of treating a chelating agent solution having radioactive contaminants, which can significantly decrease the amount of the chelating agent solution having radioactive contaminants, and which, when an ion-exchange resin is used, can significantly decrease the load on the ion-exchange resin without producing a large amount of ion-exchange resin having radioactive contaminants.

Abstract: The present invention relates to an electrolysis cell for percolating a solution in order to perform a chemical reaction, such as the cathodic reduction of a metal cation.This cell includes for example a bed of cathodically biased particles 31, a plurality of counter-electrodes 33, located at the periphery of the bed of particles and anodically biased and an additional counter-electrode 38, anodically biased and located at the center of the bed.This arrangement allows to modify the electrode potential inside the bed, in order to avoid the unwanted electrochemical reactions.

Abstract: Metal salts are removed from solution in an electrolyte by subjecting the solution to electrolysis in a cell having an anode that has an anion exchange membrane closely associated therewith which sequesters the anion of the salt. The cathode may also be provided with a closely associated cation exchange membrane that sequesters, at least partially, the cation of the salt. A metal salt solution can be regenerated by reversing the polarity of the electrodes and conducting an electrolysis using fresh electrolyte.

Abstract: A method and apparatus for separating heavy metal ions from a processing solution includes a filter. A cylindrical separating member divides the filter into two discrete compartments, an inner cylindrical portion and an outer annular portion concentrically arranged outside the inner cylindrical portion. The separating member is made of chemical and heat resistant material. The processing solution is made to flow through the inner portion in one direction and a gas is made to flow through the outer portion in the opposite direction. The flowing has negatively charges the separating member, which results in formation of an electrical double layer on the surface where the processing solution contacts the separating member. The heavy metal ions in the processing solution, which ions are positively charged, are attracted and adsorbed to the negatively charged separating member, thus removing the heavy metal ions from the processing solution.

Abstract: The present invention concerns a process for the electrolytic extraction of the tin found a quantity of less than 1 g/l and in a chelated form in organic solutions.The process consists of using an electrolysis unit comprising an anode compartment and cathode compartment separated by a physical barrier, introducing the organic solution into the cathode compartment and carrying out the electrolysis in galvanostatic or potentiostatic mode.This process can be applied to the recycling of photographic effluents containing tin, in particular to the processing of reversal products.

Abstract: Effluent streams from photographic processes contain both silver and thiosulphate ions, and because of the formation of complex anions it is difficult to remove the silver. The silver may be removed using a cell (12) with a cathode (24) exposed to the effluent liquid, and an anode (25) separated from the liquid by a barrier (22) permeable at least to anions. Some silver sulphide is formed electrochemically at the cathode (24); at the anode (25) water is electrolysed and becomes acidic, so the complex anions migrating through the barrier (22) generate silver sulphide chemically. The resulting silver sulphide precipitate is separated from the liquid by a filter (14).