Abstract: A side stream subsystem can be used to remove impurity species from the recirculating alkali metal chloride solution in certain electrolysis systems. Silicon and/or aluminum species can be removed via precipitation after introducing an alkali metal hydroxide and magnesium chloride in a side stream line in the subsystem. The invention can allow for a substantial reduction in raw material and capital costs.

Abstract: A process for producing alkali metal chlorate that includes introducing an electrolyte solution containing alkali metal halide and alkali metal chlorate to an electrolytic cell, electrolyzing the electrolyte solution to produce an electrolyzed chlorate solution, transferring the electrolyzed chlorate solution to a chlorate reactor to produce a more concentrated alkali metal chlorate, wherein the electrolytic cell is a non-divided electrolytic cell that includes: at least one anode or at least one cathode that includes an electrode substrate comprising M(n+1)AXn, where M is a metal of group IIIB, IVB, VB, VIB or VIII of the periodic table of elements or a combination thereof, A is an element of group IIIA, IVA, VA or VIA of the periodic table of elements or a combination thereof, X is carbon, nitrogen or a combination thereof, where n is 1, 2, or 3; and an outlet for transferring electrolyzed solution to the chlorate reactor.

Abstract: The invention relates to a process for producing alkali metal chlorate in an electrolytic cell that is divided by a cation selective separator into an anode compartment in which an anode is arranged and a cathode compartment in which a gas diffusion electrode is arranged. The process comprises introducing an electrolyte solution containing alkali metal chloride into the anode compartment and an oxygen-containing gas into the cathode compartment. The invention also relates to an electrolytic cell for the production of alkali metal chlorate comprising a cation selective separator dividing the cell into an anode compartment in which an anode is arranged and a cathode compartment in which a gas diffusion electrode is arranged. An inlet for electrolyte solution and an outlet for electrolysed solution are provided in the anode compartment and an inlet for introducing oxygen-containing gas is provided in the gas chamber.

Abstract: Method and apparatus for controlling two phase flow in electrolytic cells. The present invention is directed to any electrolytic cell, including but not limited to upflow electrolytic cells that comprise parallel electrodes in a vertical orientation. Fluid control strips are preferably added between the anode and cathode electrodes to control flow of fluid and gas bubbles generated between the electrodes in order to avoid the detrimental effects of gas bubbles on the conductivity of the fluid solution, and thereby increase production and operational efficiency of the electrolytic cell.

Abstract: A process for the production of chlorates and derivative chemicals from ammonium perchlorate as a starting material. Ammonia is produced in a first step wherein a metal hydroxide is reacted with ammonium perchlorate to produce ammonia and a metal perchlorate. If the metal hydroxide used is sodium hydroxide, sodium perchlorate is formed. The ammonia generated is recovered and sent to a reformer to produce hydrogen which is used to fuel a fuel cell that generates water and electrical energy to run an electrochemical reactor where the metal perchlorate is converted to a metal chlorate and derivative chemicals.

Abstract: A batch or continuous process for the removal by flocculation of silicon and heavy metal contamination from aqueous waste streams by the addition of an aluminum salt, particularly, aqueous streams recycled as electrolyte in the electrolytic production of alkali metal or alkaline earth metal chlorates. The process is particularly suited to the removal of heavy metals and silicon contamination in an electrolyte recycled to an electrolytic cell subsequent to the removal by crystallization of a chlorate salt. An aluminum salt, such as aluminum chloride, aluminum chlorohydrate, and polyaluminum chlorides including polyaluminum chloride sulfates is effective as a flocculating agent.

Abstract: Chlorine dioxide is generated by electrochemical oxidation of sodium chlorite in an anode compartment of a cation-exchange membrane-divided cell in the presence of significant quantities of sodium chlorate and is recovered in a suitable recipient medium by passing the chlorine dioxide through a hydrophobic microporous membrane. Water balance in a continuous operation is maintained by removing water from the anolyte by transporting the same partly across the hydrophobic microporous membrane in vapor form and partly across the cation-exchange membrane.

Abstract: Chlorine dioxide is generated by electrochemical oxidation of sodium chlorite in an anode compartment of a cation-exchange membrane-divided cell and is recovered in a suitable recipient medium by passing the chlorine dioxide through a hydrophobic microporous membrane. Water balance in a continuous operation is maintained by removing water from the anolyte by transporting the same partly across the hydrophobic microporous membrane in vapor form and partly across the cation-exchange membrane.