A method for producing a vanadate extracts a vanadium component included in combustion fly ash or clinker. In the method, a vanadium component is recovered as a vanadate from combustion fly ash or clinker, the method including the following steps 1 to 5: (1) a step of adding an aqueous sodium hydroxide solution to combustion fly ash or clinker so that the water content is 5 to 35% by mass (step 1); (2) a step of mixing or kneading (step 2); (3) a step of heating the mixed or kneaded mixture (step 3); (4) a step of adding water to the mixture that has undergone the heating step in the step 3 to form a slurry (step 4); and (5) a step of recovering a vanadate in the aqueous phase after the solid-liquid separation of the slurry (step 5).

Disclosed is a method for preparing vanadium or vanadium alloy powder from a vanadium-containing raw material through a shortened process, including: calcinating a mixture of a vanadium-containing raw material and an alkali compound for oxidation to form a water-soluble vanadate; purifying the vanadate followed by vanadium precipitation to produce an intermediate CaV.sub.2O.sub.6 with high purity; dissolving CaV.sub.2O.sub.6 in a molten-salt medium together with other raw materials to form a uniform reaction system; and introducing a reducing agent to the system followed by separation, washing and drying to produce vanadium or vanadium alloy powder having a particle size of 50-800 nm and a purity of 99.0 wt % or more. The method can continuously process vanadium-containing raw materials to prepare vanadium or vanadium alloy powder.

The present invention relates to a process for the separation of vanadium in the form of vanadium oxide, iron-vanadium-oxide, or iron-vanadium from solutions containing both dissolved iron and dissolved vanadium, wherein an aqueous solution containing dissolved iron and vanadium in a molar iron-to-vanadium ratio of above 1:1, preferably above 1:1 and up to 10000:1, more preferably between 5:1 and 1000:1, even more preferably between 5:1 and 100:1, and most preferably between 10:1 and 50:1 and optionally also other elements is oxidized in an oxidation step with a gaseous oxidation media, and wherein the amount of acid in the aqueous solution is kept below the stoichiometric amount of acid required during bivalent iron oxidation and the precipitate thus formed is removed from the solution.

The present invention relates to a process for the separation of vanadium in the form of vanadium oxide, iron-vanadium-oxide, or iron-vanadium from solutions containing both dissolved iron and dissolved vanadium, wherein an aqueous solution containing dissolved iron and vanadium in a molar iron-to-vanadium ratio of above 1:1, preferably above 1:1 and up to 10000:1, more preferably between 5:1 and 1000:1, even more preferably between 5:1 and 100:1, and most preferably between 10:1 and 50:1 and optionally also other elements is oxidized in an oxidation step with a gaseous oxidation media, and wherein the amount of acid in the aqueous solution is kept below the stoichiometric amount of acid required during bivalent iron oxidation and the precipitate thus formed is removed from the solution.

The present disclosure broadly relates to a process for recovering scandium and/or vanadium values from various feedstocks. More specifically, but not exclusively, the present disclosure relates to a process for the selective recovery of scandium and/or vanadium values from a feedstock, the process comprising: leaching the feedstock in a sulfuric acid solution while simultaneously sonicating the sulfuric acid solution thereby producing a pregnant solution; and selectively removing scandium and vanadium compounds from the pregnant solution using a solvent extraction process.

The present disclosure broadly relates to a process for recovering scandium and/or vanadium values from various feedstocks. More specifically, but not exclusively, the present disclosure relates to a process for the selective recovery of scandium and/or vanadium values from a feedstock, the process comprising: leaching the feedstock in a sulfuric acid solution while simultaneously sonicating the sulfuric acid solution thereby producing a pregnant solution; and selectively removing scandium and vanadium compounds from the pregnant solution using a solvent extraction process.

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.

A method (10) for preparing a leach feed material, the method (10) comprising the steps of: passing an ore or concentrate containing vanadium and iron to a reduction step (12) to form a reduced ore or concentrate; and passing the reduced ore or concentrate to a ferric leach step (14) to produce a ferric leachate containing iron and a ferric leach residue containing vanadium,
wherein the ferric leach residue is suitable for use as the leach feed material for extracting and recovering vanadium.

A method (10) for preparing a leach feed material, the method (10) comprising the steps of: passing an ore or concentrate containing vanadium and iron to a reduction step (12) to form a reduced ore or concentrate; and passing the reduced ore or concentrate to a ferric leach step (14) to produce a ferric leachate containing iron and a ferric leach residue containing vanadium,
wherein the ferric leach residue is suitable for use as the leach feed material for extracting and recovering vanadium.

The present invention discloses a process for recovering ammonia from vanadium preparation for ammonium preparation and recycling wastewater. A conventional vanadium extraction process is complex, and the most difficult to control and treat are ammonia emissions and wastewater treatment. The present process can directly extract ammonium metavanadate and ammonium polyvanadate from the beginning of mining and smelting, and gather all emitted ammonia to prepare ammonium in the process of preparing high-purity vanadium pentoxide by using the ammonium metavanadate or the ammonium polyvanadate, thereby ensuring zero emission of the exhaust gas, and effectively treat all wastewater generated in the above process by using a polyacid ester folucculation technology, thereby ensuring that the wastewater is not discharged but recycled, and realizing that the purity of all products reaches 99.5-99.99%.