Disclosed is a carbon dioxide utilization system capable of recharging and undergoing reactions. The system includes a cathode unit provided with a first aqueous solution accommodated in a first accommodation space, and a cathode at least a part of which is submerged in the first aqueous solution; an anode unit provided with an alkaline second aqueous solution accommodated in a second accommodation space, and a metal anode at least a part of which is submerged in the second aqueous solution; and a connection unit provided with a connection channel connecting the first and second accommodation spaces in open communication, and a porous ion transfer member, disposed in the connection channel, for blocking the movement of the first and second aqueous solutions but allowing the movement of ions.

The method for operating a water electrolysis device for generating hydrogen and oxygen from water has a PEM electrolyser (1), to which water for generating the hydrogen and the oxygen is supplied together with water for cooling. The cooling water is conducted in the circuit and treated by means of an ion exchanger unit (17). Only part of the water conducted in the circuit is supplied to the ion exchanger unit (17) and another part is supplied to the PEM electrolyser (1) via a bypass (13) circumventing the ion exchanger unit (17).

The method for operating a water electrolysis device for generating hydrogen and oxygen from water has a PEM electrolyser (1), to which water for generating the hydrogen and the oxygen is supplied together with water for cooling. The cooling water is conducted in the circuit and treated by means of an ion exchanger unit (17). Only part of the water conducted in the circuit is supplied to the ion exchanger unit (17) and another part is supplied to the PEM electrolyser (1) via a bypass (13) circumventing the ion exchanger unit (17).

Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to carbon monoxide or formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing carbon monoxide or formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

##STR00001##

Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to carbon monoxide or formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing carbon monoxide or formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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Compositions comprising hydrogenated and dehydrogenated graphite comprising a plurality of flakes. At least one flake in ten has a size in excess of ten square micrometers. For example, the flakes can have an average thickness of 10 atomic layers or less.

Compositions comprising hydrogenated and dehydrogenated graphite comprising a plurality of flakes. At least one flake in ten has a size in excess of ten square micrometers. For example, the flakes can have an average thickness of 10 atomic layers or less.

The present invention relates to systems and methods for cleaning materials, such as flooring and upholstery. In some cases, the systems and methods use an electrolytic cell to electrolyze a solution comprising sodium carbonate, sodium bicarbonate, sodium acetate, sodium percarbonate, potassium carbonate, potassium bicarbonate, and/or any other suitable chemical to generate electrolyzed alkaline water and/or electrolyzed oxidizing water. In some cases, the cell comprises a recirculation loop that recirculates anolyte through an anode compartment of the cell. In some cases, the cell further comprises a senor and a processor, where the processor is configured to automatically change an operation of the cell, based on a reading from the sensor. In some cases, a fluid flows past a magnet before entering the cell.

In some additional cases, fluid from the cell is conditioned by being split into multiple conduits that run in proximity to each other. Additional implementations are described.

The present invention concerns a method for modifying the properties of the surface (F) of a material. The method comprises the following steps: preparing a first layer (12; 12) comprising an electrically conductive material suited to serve the function of a cathode, a second layer (14) comprising an electrically conductive material suited to serve the function of an anode and an intermediate layer (16) suited to become impregnated with an electrolyte in the liquid phase or to regulate its flow between said cathode and said anode; associating an electrolyte in the liquid phase with one or more of said layers (12, 14, 16); positioning the anode or the cathode on the surface (F) to be treated; supplying power to the cathode and the anode in order to activate the electrochemical process of the electrolyte in the liquid phase for a predetermined time interval.

The present invention concerns a method for modifying the properties of the surface (F) of a material. The method comprises the following steps: preparing a first layer (12; 12) comprising an electrically conductive material suited to serve the function of a cathode, a second layer (14) comprising an electrically conductive material suited to serve the function of an anode and an intermediate layer (16) suited to become impregnated with an electrolyte in the liquid phase or to regulate its flow between said cathode and said anode; associating an electrolyte in the liquid phase with one or more of said layers (12, 14, 16); positioning the anode or the cathode on the surface (F) to be treated; supplying power to the cathode and the anode in order to activate the electrochemical process of the electrolyte in the liquid phase for a predetermined time interval.