Methods and systems for removing impurities from electrolyte solutions having three or more valence states. In some embodiments, a method includes electrochemically reducing an electrolyte solution to lower its valence state to a level that causes impurities to precipitate out of the electrolyte solution and then filtering the precipitate(s) out of the electrolyte solution. In embodiments in which the electrolyte solution is desired to be at a valence state higher than the precipitation valence state, a method of the disclosure includes oxidizing the purified electrolyte solution to the target valence.

A redox flow battery system includes an anolyte having a first ionic species in solution; a catholyte having a second ionic species in solution, where the redox flow battery system is configured to reduce the first ionic species in the anolyte and oxidize the second ionic species in the catholyte during charging; a first electrode in contact with the anolyte, where the first electrode includes channels for collection of particles of reduced metallic impurities in the anolyte; a second electrode in contact with the catholyte; and a separator separating the anolyte from the catholyte. A method of reducing metallic impurities in an anolyte of a redox flow battery system includes reducing the metallic impurities in the anolyte; collecting particles of the reduced metallic impurities; and removing the collected particles using a cleaning solution.

A redox flow battery system includes an anolyte having a first ionic species in solution; a catholyte having a second ionic species in solution, where the redox flow battery system is configured to reduce the first ionic species in the anolyte and oxidize the second ionic species in the catholyte during charging; a first electrode in contact with the anolyte, where the first electrode includes channels for collection of particles of reduced metallic impurities in the anolyte; a second electrode in contact with the catholyte; and a separator separating the anolyte from the catholyte. A method of reducing metallic impurities in an anolyte of a redox flow battery system includes reducing the metallic impurities in the anolyte; collecting particles of the reduced metallic impurities; and removing the collected particles using a cleaning solution.

A hybrid photoactive heterojunction including a copper vanadate, Cu.sub.2V.sub.2O.sub.7 (CVO) and a zinc vanadate, Zn.sub.2V.sub.2O.sub.6 (ZVO). Particles of the ZVO are dispersed in particles of the CVO to form the hybrid photoactive heterojunction. The hybrid photoactive heterojunction in the form of a photoactive film includes a substrate which is at least partially coated with the hybrid photoactive heterojunction. A method of photodegrading a dye includes contacting the photoactive film and the dye in a solution and exposing the solution to light. A method of photoelectrochemically oxidizing water includes contacting the photoactive film with water in a solution and exposing the solution to light.

A hybrid photoactive heterojunction including a copper vanadate, Cu.sub.2V.sub.2O.sub.7 (CVO) and a zinc vanadate, Zn.sub.2V.sub.2O.sub.6 (ZVO). Particles of the ZVO are dispersed in particles of the CVO to form the hybrid photoactive heterojunction. The hybrid photoactive heterojunction in the form of a photoactive film includes a substrate which is at least partially coated with the hybrid photoactive heterojunction. A method of photodegrading a dye includes contacting the photoactive film and the dye in a solution and exposing the solution to light. A method of photoelectrochemically oxidizing water includes contacting the photoactive film with water in a solution and exposing the solution to light.

Materials, designs, methods of manufacture, and devices are provided for an anode material for a rechargeable lithium-ion battery. For example, an anode material may include Li.sub.3±xV.sub.2±yO.sub.5±z, wherein 0≤x≤7, 0≤y≤1, and z may be based on the charge resulting from Li.sub.3±x and V.sub.2±y. Also, a cell can include a lithiated anode material. The lithiated anode material may include Li.sub.3±xV.sub.2±y O.sub.5±z. The lithiated anode material may be casted on a first substrate to form a lithiated anode, having a separator stacked on the lithiated anode. The separator may include electrolytes. A cathode can be stacked on the separator. The cathode being formed by casting a cathode material on a second substrate.

Materials, designs, methods of manufacture, and devices are provided for an anode material for a rechargeable lithium-ion battery. For example, an anode material may include Li.sub.3±xV.sub.2±yO.sub.5±z, wherein 0≤x≤7, 0≤y≤1, and z may be based on the charge resulting from Li.sub.3±x and V.sub.2±y. Also, a cell can include a lithiated anode material. The lithiated anode material may include Li.sub.3±xV.sub.2±y O.sub.5±z. The lithiated anode material may be casted on a first substrate to form a lithiated anode, having a separator stacked on the lithiated anode. The separator may include electrolytes. A cathode can be stacked on the separator. The cathode being formed by casting a cathode material on a second substrate.

The present invention relates to metallurgical processes, and more particularly to a process for producing titaniferous feedstock and fines, a process for agglomerating titaniferous fines, and a process for producing titaniferous metals and titaniferous alloys. Recovery of rare-earth, vanadium and scandium from titanium iron bearing resources is also disclosed. Selective leaching for Scandium recovery from all magnetite type resources such as ilmenite, ferro titanic resources, nickel laterites, magnetite iron resources etc.

A CoVO.sub.x composite electrode and method of making is described. The composite electrode comprises a substrate with an average 0.5-5 μm thick layer of CoVO.sub.x having pores with average diameters of 2-200 nm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a cobalt complex, and a vanadium complex. The CoVO.sub.x composite electrode is capable of being used in an electrochemical cell for water oxidation.

Provided are a selective recovery method of vanadium and cesium from a waste sulfuric acid vanadium catalyst by a hydrometallurgical method including water leaching, solid-liquid separation, vanadium solvent extraction, vanadium selective stripping, and cesium alum production, and a high-quality vanadium aqueous solution and cesium alum produced thereby.