Abstract:
Multipurpose electrolytic device (EMPD) for forced or spontaneous electrolytic processes, which incorporates selective and unidirectional ion exchange membranes in order to separate between two or more compartments and allow electrical conductivity therebetween, with independent electrolytes for controlled electrolytic ion transformation, regardless of the chemical composition of the electrolyte containing the element of interest, with high faradaic efficiency and high energy performance. The invention also relates to a method. The device can be used for processes such as metal electrowinning (EW), metal electrorefining, electrooxidation (EOXI) and electroreduction (ERED) of ionic species. The device uses two independent, energetically suitable electrolytes, which allow controlled electrolytic ion transformation, with high faradaic efficiency and high energy performance, unlike current forced electrolysis methods, which operate with a common electrolyte. The device can be used in any aqueous medium, for example an acid environment, such as sulphuric, hydrochloric or other acid, a caustic-soda-based alkaline, or ammonium, thiocyanate or thiosulfate salts, with or without the presence of organic reactants.
Abstract:
A system to remove sodium and Sulfur from a feed stream containing alkali metal sulfides and polysulfides in addition to heavy metals. The system includes an electrolytic cell having an anolyte compartment housing an anode in contact with an anolyte. The anolyte includes alkali metal sulfides and polysulfides dissolved in a polar organic solvent. The anolyte includes heavy metal ions. A separator includes an ion conducting membrane and separates the anolyte compartment from a catholyte compartment that includes a cathode in contact with a catholyte. The catholyte includes an alkali ion-conductive liquid. A power source applies a voltage to the electrolytic cell high enough to reduce the alkali metal and oxidize Sulfur ions to allow recovery of the alkali metal and elemental sulfur. The ratio of sodium to Sulfur is such that the open circuit potential of the electrolytic cell is greater than about 2.3V.
Abstract:
An electrochemical cell and methods of using the electrochemical cell are described that can be utilized for the recovery of metals from metal oxides. The cell includes a first electrode that includes a solid metal oxide, an electrolyte including an oxygen ion conductor, and a second electrode space apart from the electrolyte by an oxygen ion conducting membrane. Upon reduction of the metal oxide, solid metal is formed that replaces the metal oxide of the electrode and provides for simplified recovery of the metal from the metal oxide. The membrane protects the second electrode from corrosion and degradation from the electrolyte, increasing the life of the cell.
Abstract:
A cathode assembly, a system including the cathode assembly, and method of using the assembly and system are disclosed. The cathode assembly includes a conductive element and a barrier element proximate the conductive element. The assembly, system and method provide for improved metal powder formation. The system may be stationary or portable.
Abstract:
A porous sheet which has good balance between electrolytic solution permeability and dry-up resistance, is superior in high-rate property, and is suitable for a separator for an electrochemical element, and a manufacturing method thereof are provided.The present invention relates to a porous sheet comprising a porous substrate containing non-fibrillar fibers having an average fiber diameter of 0.01-10 μm and a net-like structural body composed of a polymer, the net-like structural body having penetrating pores with a pore diameter of 0.01-10 μm, wherein the net-like structural body is present at the surface and at the internal of the porous substrate and the non-fibrillar fibers having an average fiber diameter of 0.01-10 μm and the net-like structural body are entangled; to a separator for an electrochemical element comprising the porous sheet; and to a method for manufacturing the porous sheet.
Abstract:
An electrochemical cell having two or more diffusion bonded layers, which demonstrates a high degree of ruggedness, reliability, efficiency and attitude insensitiveness, is provided. The novel cell structure simplifies construction and operation of these cells. Also provided is a method for passive water removal from these cells. The inventive cell, as well as stacks made using these cells, is suitable for use in applications such as commercial space power systems, long endurance aircraft, undersea power systems, remote backup power systems, and regenerative fuel cells.
Abstract:
In various aspects, provided are substantially single phase ceramic membranes, gas separation devices based thereon, and methods of making the membranes. In various embodiments, the membranes and devices can be used for hydrogen production, such as in a fuel-cell.
Abstract:
An electrochemical cell for electrochemical reduction of a metal oxide in a solid state is disclosed. The cell includes a molten electrolyte (14), an anode (10) formed from carbon in contact with the electrolyte, a cathode (20) formed at least in part from the metal oxide in contact with the electrolyte, and a membrane (28) that is permeable to oxygen anions and is impermeable to carbon in ionic and non-ionic forms positioned between the cathode and the anode to thereby prevent migration of carbon from the anode to the cathode. The membrane includes a body (32) and a lining (34) on the surface of the body on the cathode side of the membrane. The lining is formed from a material that is inert with respect to dissolved metal in the electrolyte and is impermeable to the dissolved metal. An electrochemical method based on the cell is also disclosed.
Abstract:
A support member is useful for supporting membranes such as solid polymer electrolyte ion exchange membranes such as those used in electrochemical cell applications. The support member has a first lattice pattern on a first side of a single piece of material. A second lattice pattern on a second side of the single piece of material cooperates with the first lattice pattern to establish a plurality of flow passages across the material. Each lattice pattern has a corresponding plurality of recesses that extend partway through the material and overlapping portions of the recesses define the flow passages. In a disclosed example, the monolithic support member lattice patterns are established using chemical etching.
Abstract:
A proton conductive membrane exhibiting superior proton conductivity even at high temperatures of 100° C. or above, and a proton conductive composition capable of forming the membrane are provided. The invention also provides a proton conductive membrane showing excellent proton conductivity even if it does not have an increased amount of the sulfonic groups introduced therein, and a proton conductive composition capable of forming the membrane. The proton conductive composition includes (a) at least one compound selected from a metal oxide hydrate, a phyllosilicate and a hygroscopic inorganic porous compound, and (b) a polyarylene having a sulfonic group.