摘要:
In a method of removing impurities, especially iodine and/or silica ions, from a salt solution to be used for electrolysis, the salt solution and zirconium hydroxide are brought into contact with each other under acidic conditions, and the zirconium hydroxide adsorbs the impurities. Thereafter, the zirconium hydroxide containing the adsorbed impurities is brought into contact with an aqueous solution at a higher pH value to desorb the impurities from the zirconium hydroxide, thereby enabling the zirconium hydroxide to be recycled.
摘要:
In an activated cathode and a method for manufacturing the activated cathode, a first layer which contains nickel or cobalt as a main component is formed on a metal substrate, and a second layer which contains platinum or ruthenium as a main component is formed on the first layer. It is preferable that the first layer is formed of Raney nickel and the second layer has a large cathode working area, or it is also preferable that the first layer is formed of nickel oxide or cobalt oxide, and the second layer is formed of fine platinum or ruthenium particles and has a large cathode working area.
摘要:
Disclosed is a method for preventing a low hydrogen overvoltage cathode from degradation in activity characterized by adding a reducing agent to a cathode compartment of an electrolytic cell which electrolysis an aqueous alkali metal halide solution. According to the invention, no degradation takes place even after repeated shutdown of operation.
摘要:
The present invention provides an ozone generator comprising an anode and a cathode provided on each side of a fluororesin type cation exchange membrane, the anode being a conductive diamond electrode having conductive diamond on the surface, wherein water is supplied to an anode compartment, DC current is supplied between the anode and the cathode to electrolyze water to evolve ozone from the anode compartment and hydrogen from a cathode compartment, the conductive diamond electrode comprising a substrate having a plurality of convexo-concave and a conductive diamond film coated on the surface of the substrate is applied as the conductive diamond electrode, and a close packed layer of ion exchange resin particles or the fluororesin type cation exchange membrane with notch is closely adhered to the surface of the anode side of the fluororesin type cation exchange membrane.
摘要:
The cleaning method by electrolytic sulfuric acid and the manufacturing method of semiconductor device comprising: the process in which the first sulfuric acid solution is supplied from outside to the sulfuric acid electrolytic cell to form the first electrolytic sulfuric acid containing oxidizing agent in the sulfuric acid electrolytic cell; the process in which the second sulfuric acid solution, which is higher in concentration than said the first sulfuric acid solution previously supplied, is supplied from outside to said sulfuric acid electrolytic cell; said the second sulfuric acid solution and the first electrolytic sulfuric acid are mixed in said sulfuric acid electrolytic cell; and electrolysis is performed to form the cleaning solution comprising the second electrolytic sulfuric acid containing sulfuric acid and oxidation agent in said sulfuric acid electrolytic cell and the process in which cleaning treatment is performed for the cleaning object with said cleaning solution.
摘要:
In a cooking process of a lignocellulose material, pulp yield can be improved at the same Kappa number and an effective alkali addition rate can be reduced at the same Kappa number.In a continuous cooking process making use of a digester, which includes therein, from a top toward a bottom of the digester, a top zone, an upper cooking zone, a lower cooking zone and a cooking/washing zone and also includes strainers provided at the bottom of the respective zones and wherein a cooking black liquor extracted from at least one of the strainers is discharged to outside a digestion system, a process for cooking a lignocellulose characterized by comprising feeding, upstream of the top of the digester, a first cooking liquor comprised of an alkaline cooking liquor having specified composition, feeding a second cooking liquor comprised of an alkaline cooking liquor made mainly of sodium hydroxide to the upper cooking zone, and feeding a third cooking liquor comprised of an alkaline cooking liquor similar to the second cooking liquor to the cooking/washing zone.
摘要:
The present invention provides a method for manufacturing hypochlorite efficiently, using an anode, which has a coating containing palladium oxide by 10 to 45 weight %, ruthenium oxide by 15 to 45 weight %, titanium dioxide by 10 to 40 weight %, and platinum by 10 to 20 weight % as well as an oxide of at least one metal selected from cobalt, lanthanum, cerium or yttrium by 2 to 10 weight % being formed on a conductive base, and a cathode comprising a coating having low hydrogen overvoltage and covered with a reduction preventive film and being formed on a conductive base, and an aqueous solution of a chloride is electrolyzed without a diaphragm.
摘要:
A method for controlling chlorates in an aqueous alkali metal hydroxide liquor produced by an ion exchange membrane electrolysis is provided, which comprises adding a reducing agent to brine to keep the concentration of chlorates to a specified value or less. The present invention provides an alkali metal hydroxide liquor with low content of chlorates.
摘要:
The present invention provides an ozone generator comprising an anode and a cathode provided on each side of a fluororesin type cation exchange membrane, the anode being a conductive diamond electrode having conductive diamond on the surface, wherein water is supplied to an anode compartment, DC current is supplied between the anode and the cathode to electrolyze water to evolve ozone from the anode compartment and hydrogen from a cathode compartment, the conductive diamond electrode comprising a substrate having a plurality of convexo-concave and a conductive diamond film coated on the surface of the substrate is applied as the conductive diamond electrode, and a close packed layer of ion exchange resin particles or the fluororesin type cation exchange membrane with notch is closely adhered to the surface of the anode side of the fluororesin type cation exchange membrane.
摘要:
In removal of sulfate groups and chlorate groups from brine used for electrolysis, concentrated brine used in an electrolysis process or dilute brine whose concentration is decreased by electrolysis is fed to an anode chamber divided by a cation exchange membrane in a brine treating electrolyzer, where the concentrated or dilute brine is electrolyzed to recover chloride ions therein. The concentrated brine is electrolyzed at a rate of decomposition of salt higher than that in the ion exchange membrane electrolysis process of brine. Thereafter, the concentrated or dilute brine is discharged out of the electrolysis process.