Provided is a method that allows for efficient removal of an impurity metal, and further, the recovery of a valuable metal with high efficiency. The method for recovering a valuable metal (Cu, Ni, and Co) includes the steps of: preparing a charge comprising at least a valuable metal as a raw material; heating and melting the raw material to form an alloy and a slag; and separating the slag to recover the alloy containing the valuable metal, wherein the heating and melting of the raw material comprises charging the raw material into a furnace of an electric furnace equipped with an electrode therein, and further melting the raw material by means of Joule heat generated by applying an electric current to the electrode, or heat generation of an arc itself, and thereby separating the raw material into a molten alloy and a molten slag present over the alloy.

The present invention is a process for directly recovering lithium and valuable transition metals such as cobalt, nickel and manganese from waste cathode and anode powder of spent lithium ion batteries into high grade products through a cascade reduction reaction scheme, followed by digestion and precipitation circuit using CO.sub.2 as media, and a series of physical separation procedures.

The present invention provides a method which is capable of more strictly controlling the oxygen partial pressure required during the melting of a starting material, thereby being capable of recovering a valuable metal more efficiently. A method for recovering valuable metals (Cu, Ni, Co), said method comprising the following steps: a step for preparing, as a starting material, a charge that contains at least phosphorus (P), iron (Fe) and valuable metals; a step for heating and melting the starting material into a melt, and subsequently forming the melt into a molten material that contains an alloy and slag; and a step for recovering the alloy that contains valuable metals by separating the slag from the molten material. With respect to this method for recovering valuable metals, the oxygen partial pressure in the melt is directly measured with use of an oxygen analyzer when the starting material is heated and melted.

Proposed is a method of preparing high-purity lithium carbonate through reduction calcining of waste cathode materials without using a carbonate such as sodium carbonate. The method reduces the amount of water required for lithium carbonate recovery, thereby reducing energy consumption for evaporation of water. The method includes (a) preparing scrap powder, (b) reducing and calcining the scrap powder using activated carbon, (c) preparing a lithium hydrogen carbonate solution by adding carbon dioxide gas and the reduced and calcined scrap powder to 8° C. to 12° C. soft water, (d) separating the lithium hydrogen carbonate solution into solid and liquid; (e) converting lithium hydrogen carbonate into lithium carbonate by heating, evaporating, and concentrating the lithium hydrogen carbonate solution, and (f) obtaining the lithium carbonate through filtration.

A process for direct reduction of iron ore in a solid state includes exposing briquettes of iron ore fragments and biomass to electromagnetic energy under anoxic conditions and generating heat within iron ore in the briquettes. The iron ore is reduced in a solid state within the briquettes, and the biomass provides a source of reductant.

A process for direct reduction of iron ore in a solid state includes exposing briquettes of iron ore fragments and biomass to electromagnetic energy under anoxic conditions and generating heat within iron ore in the briquettes. The iron ore is reduced in a solid state within the briquettes, and the biomass provides a source of reductant.

A process for the production of calcium, aluminum, and silicon alloys is provided. The process includes the simultaneous carbothermal melting-reduction step of calcium, aluminum, and silicon.

A process for the production of calcium, aluminum, and silicon alloys is provided. The process includes the simultaneous carbothermal melting-reduction step of calcium, aluminum, and silicon.

Disclosed is a method for preparing an elemental material by reduction using monoatomic carbon, comprising: in a melt medium at a temperature of from 300° C. to 1500° C., cracking an organic carbon source into atomic carbon and dissolving the atomic carbon in the melt medium, allowing the atomic carbon to reduce an elemental precursor compound present in the melt medium by an oxidation-reduction reaction to generate an elemental material, and obtaining the elemental material by supersaturating and crystallizing. The method of the present invention can prepare the elemental materials with high quality by self-crystallization growth at a lower temperature and at a lower cost.

Disclosed is a method for preparing an elemental material by reduction using monoatomic carbon, comprising: in a melt medium at a temperature of from 300° C. to 1500° C., cracking an organic carbon source into atomic carbon and dissolving the atomic carbon in the melt medium, allowing the atomic carbon to reduce an elemental precursor compound present in the melt medium by an oxidation-reduction reaction to generate an elemental material, and obtaining the elemental material by supersaturating and crystallizing. The method of the present invention can prepare the elemental materials with high quality by self-crystallization growth at a lower temperature and at a lower cost.