The invention concerns a process for the electrochemical production of formate. The process is performed in an electrochemical cell comprising a cathode compartment containing a cathode, an anode compartment containing a nickel-based anode and an ion exchange membrane separating the anode compartment from the cathode compartment. The process comprises the following steps: (a) feeding an anolyte comprising at least one polyol to the anode compartment; (b) feeding a catholyte comprising CO.sub.2 to the cathode compartment; (c) and applying a voltage difference between the cathode and the anode such that at the cathode CO.sub.2 is reduced to formate and at the anode the at least one polyol is oxidized to formate.

The invention relates to an apparatus and a method for performing electrolysis with an originally oxygen-containing alkali hydroxide solution as an electrolyte precursor, wherein the pressure and temperature of the alkali hydroxide solution and the O.sub.2 content thereof are set.

The invention relates to an apparatus and a method for performing electrolysis with an originally oxygen-containing alkali hydroxide solution as an electrolyte precursor, wherein the pressure and temperature of the alkali hydroxide solution and the O.sub.2 content thereof are set.

A method for operating an electrolysis system which includes an electrolyzer for generating hydrogen and oxygen as product gases, the product gas streams being discharged from the electrolyzer. A secondary gas is mixed with at least one of the product gas streams with the goal of reducing the foreign gas concentration in the product gas stream to be treated by an increase of the overall volume flow.

A method for operating an electrolysis system which includes an electrolyzer for generating hydrogen and oxygen as product gases, the product gas streams being discharged from the electrolyzer. A secondary gas is mixed with at least one of the product gas streams with the goal of reducing the foreign gas concentration in the product gas stream to be treated by an increase of the overall volume flow.

A method of operating an electrochemical cell including introducing an aqueous solution into the electrochemical cell, applying a current across an anode and a cathode to produce a product, monitoring the voltage, dissolved hydrogen, or a condition of the aqueous solution, and applying the current in a pulsed waveform responsive to one of the measured parameters is disclosed. An electrochemical system including an electrochemical cell including an anode and a cathode, a source of an aqueous solution having an outlet fluidly connectable to the electrochemical cell, a sensor for measuring a parameter, and a controller configured to cause the anode and the cathode to apply the current in a pulsed waveform responsive to the parameter measurement is disclosed. Methods of suppressing accumulation of hydrogen gas within the electrochemical cell are also disclosed. Methods of facilitating operation of an electrochemical cell are also disclosed.

An electrolyzed water generating device 1 has an electrolysis chamber 40, a first feeding body 41 and a second feeding body 41 to which a DC voltage is applied, a diaphragm 43 disposed between the first feeding body 41 and the second feeding body 42 to divide the electrolysis chamber 40 into a first-polar chamber 40a and a second-polar chamber 40b, a control unit 5 for switching a polarity of the first feeding body 41 to an anode or a cathode and a polarity of the second feeding body 42 to a cathode or an anode, a flow rate sensor 22 detecting an amount of flowing water into the electrolysis chamber 40 on the cathode side per unit time, and a current detecting means 44 detecting a DC current supplied to the first feeding body 41 and the second feeding body 42. The surfaces of the first feeding body 41 and the second feeding body 42 are formed of a hydrogen storage metal. The control unit 5 calculates a concentration of hydrogen storage metal colloid based on the DC current and an integrated value of the amount of flowing water after switching the polarities.

Disclosed herein are methods and systems that relate to electrochemically producing hydrogen gas by maintaining a steady-state pH differential of greater than 1 between an anode electrolyte and a cathode electrolyte in a hydrogen-gas generating electrochemical cell.

A carbon dioxide electrolytic device according to an embodiment includes: an electrolysis cell including a reduction electrode, an oxidation electrode, a gas flow path supplying gas containing CO.sub.2 to the reduction electrode, a liquid flow path supplying an electrolytic solution containing water to the oxidation electrode, and a diaphragm separating the reduction electrode from the oxidation electrode; a first supply path connected to the gas flow path; a first discharge path connected to the gas flow path; a first moisture content detecting unit installed in the first discharge path to detect a moisture content in the gas flowing in the first discharge path; a moisture content adjusting unit configured to adjust a moisture content supplied to the reduction electrode; and a control unit configured to control the moisture content adjusting unit based on a detection signal of the first moisture content detecting unit.

A carbon dioxide electrolytic device according to an embodiment includes: an electrolysis cell including a reduction electrode, an oxidation electrode, a gas flow path supplying gas containing CO.sub.2 to the reduction electrode, a liquid flow path supplying an electrolytic solution containing water to the oxidation electrode, and a diaphragm separating the reduction electrode from the oxidation electrode; a first supply path connected to the gas flow path; a first discharge path connected to the gas flow path; a first moisture content detecting unit installed in the first discharge path to detect a moisture content in the gas flowing in the first discharge path; a moisture content adjusting unit configured to adjust a moisture content supplied to the reduction electrode; and a control unit configured to control the moisture content adjusting unit based on a detection signal of the first moisture content detecting unit.