The invention relates to a method of removing and/or recovering metals from a dilute metal containing solution. In particular, the invention concerns a method for recovering copper from a dilute copper-iron bearing mining water, particularly from a copper-iron bearing mining wastewater.

The method includes two technological segments (i) a reduction segment and (ii) an oxidation segment that are interconnected by various support technological processes for the regeneration of solutions and gases and heat recuperation. The reduction segment includes an electrolysis that is performed from a solution of chloride salts of an energy carrier. During the electrolysis, these elements reduce to a lower oxidation state, solidify on the electrodes or precipitate to a solid state. The solid substance thus obtained is the energy carrier that can be stored outside of the electrolyser until a need for additional energy emerges. During the electrolysis, chlorine gas develops that is collected and dissolved in water. An HCl solution is regenerated, which is used in the oxidation segment. Oxygen is released in this process. The energy that has thus been stored in the oxidation potential of the energy carrier is released during a spontaneous chemical reaction between the energy carrier and the HCl solution in the oxidation segment. In this chemical reaction, the oxidation state of the chemical elements which constitute the energy carrier is increased to an oxidation state identical to that from before the beginning of the electrolysis. The reaction product hydrogen is formed that represents a high calorific fuel. This fuel can be immediately converted to heat or electrical energy, without a need for intermediate storage, by known methods. Only water enters the entire method, oxygen and hydrogen leave, while the cycle is closed/cyclic for the remaining substances.

The present disclosure broadly relates to a process for recovering vanadium, iron, titanium and silica values from vanadiferous feedstocks. More specifically, but not exclusively, the present disclosure relates to a metallurgical process in which vanadium, iron, titanium and silica values are recovered from vanadiferous feedstocks such as vanadiferous titanomagnetite, iron ores, vanadium slags and industrial wastes and by-products containing vanadium. The process broadly comprises digesting the vanadiferous feedstocks into sulfuric acid thereby producing a sulfation cake; dissolving the sulfation cake and separating insoluble solids thereby producing a pregnant solution; reducing the pregnant solution thereby producing a reduced pregnant solution; and crystallizing ferrous sulfate hydrates from the reduced pregnant solution, producing an iron depleted reduced solution. The process further comprises removing titanium compounds from the iron depleted reduced solution thereby producing a vanadium-rich pregnant solution; concentrating vanadium and recovering vanadium products and/or a vanadium electrolyte.

The present disclosure broadly relates to a process for recovering vanadium, iron, titanium and silica values from vanadiferous feedstocks. More specifically, but not exclusively, the present disclosure relates to a metallurgical process in which vanadium, iron, titanium and silica values are recovered from vanadiferous feedstocks such as vanadiferous titanomagnetite, iron ores, vanadium slags and industrial wastes and by-products containing vanadium. The process broadly comprises digesting the vanadiferous feedstocks into sulfuric acid thereby producing a sulfation cake; dissolving the sulfation cake and separating insoluble solids thereby producing a pregnant solution; reducing the pregnant solution thereby producing a reduced pregnant solution; and crystallizing ferrous sulfate hydrates from the reduced pregnant solution, producing an iron depleted reduced solution. The process further comprises removing titanium compounds from the iron depleted reduced solution thereby producing a vanadium-rich pregnant solution; concentrating vanadium and recovering vanadium products and/or a vanadium electrolyte.

Provided is a novel polyoxometalate and a method for producing the polyoxometalate. The polyoxometalate is represented by the compositional formula: M.sub.xO.sub.y in which M is tungsten, molybdenum or vanadium; 4x1000; and 2.5y/x7.

Provided is a novel polyoxometalate and a method for producing the polyoxometalate. The polyoxometalate is represented by the compositional formula: M.sub.xO.sub.y in which M is tungsten, molybdenum or vanadium; 4x1000; and 2.5y/x7.

A method for desulfurization and dezincification of tailings includes the step of passing tap water into a high oxidation reduction electrocatalytic water equipment to reduce the pH value of tap water to 1-2, mixing a specific ratio of the pH value 1-2 acid electrocatalytic water with low-quality high-sulfur iron in the tailings, heating the mixture to let H.sup.+ in the acid electrocatalytic water be reacted with sulfur and zinc in the low-quality high-sulfur iron and to further cause generation of an ion state of hydrogen sulfide gas where the volatilization of water vapor effectively removes the sulfur and zinc elements in the low-quality high-sulfur iron and the hydrogen sulfide gas thus generated is collected.

A method for desulfurization and dezincification of tailings includes the step of passing tap water into a high oxidation reduction electrocatalytic water equipment to reduce the pH value of tap water to 1-2, mixing a specific ratio of the pH value 1-2 acid electrocatalytic water with low-quality high-sulfur iron in the tailings, heating the mixture to let H.sup.+ in the acid electrocatalytic water be reacted with sulfur and zinc in the low-quality high-sulfur iron and to further cause generation of an ion state of hydrogen sulfide gas where the volatilization of water vapor effectively removes the sulfur and zinc elements in the low-quality high-sulfur iron and the hydrogen sulfide gas thus generated is collected.

Provided is a method for efficiently separating and recovering tungsten and other valuable(s) from at least one valuable containing tungsten. The present invention relates to a method for recovering at least one valuable containing tungsten, comprising subjecting a raw material mixture comprising at least one valuable containing tungsten to electrolysis using an electrolytic solution containing at least one alcohol amine to dissolve tungsten in the electrolytic solution, electrodeposit a part of the valuable(s) onto a cathode used for the electrolysis and separate at least one valuable other than the valuable(s) electrodeposited onto the cathode as a residue in the electrolytic solution, and then separating and recovering each of the residue and the valuable(s) electrodeposited onto the cathode.

A device for producing a pure metal or an alloy of the pure metal via electrolytic reduction of an ore of the pure metal or of a substance containing an oxidized form of the pure metal includes: a cell equipped with an anode, a cathode, an electrolytic area comprising an electrolyte, and a removable cell closing system, the cathode having a coating non-adherent for an electrolytically deposited metal; and an electrically conductive metal sheet for extraction of a plate of the electrolytically deposited metal on the cathode, the metal sheet being arranged in the cell in a continuation of the cathode or partially overlapping the cathode, with mechanical and electrical contact at one end with the cathode and extending at least partly beyond the electrolytic area of the cell so as to allow simultaneous depositing of the pure metal on the cathode and on a portion of the metal sheet.