A copper/molybdenum separation system uses sea water in the roughing circuit and desalinated water in cleaning circuit. In both roughing circuit and cleaning circuit, hydrophobic engineered media are used to recover the mineral particles of interest. The cleaning circuit includes a molybdenum loading stage configured to contact the conditioned pulp with the engineered media in an agitated reaction chamber, and load the hydrophobic molybdenite on the engineered media.

Disclosed is a method for synthesizing copper sulfide nano powder using plasma synthesis. The method comprises providing a copper compound to a plasma apparatus, adding a sulfur, and performing a plasma process with respect to the copper compound and the sulfur for synthesizing a nano copper sulfide.

Disclosed is a method for synthesizing copper sulfide nano powder using plasma synthesis. The method comprises providing a copper compound to a plasma apparatus, adding a sulfur, and performing a plasma process with respect to the copper compound and the sulfur for synthesizing a nano copper sulfide.

A process for preparing a copper sulfide of the formula Cu.sub.xS.sub.y, wherein the process comprises the following steps: (i) reacting an aqueous solution of a copper salt with a molar excess of a sulfiding agent so as to precipitate copper sulfide from the solution; (ii) isolating the copper sulfide precipitate from the reaction mixture; and (iii) drying the copper sulfide precipitate at a temperature of less than 100 C., wherein x and y are integer or non-integer values.

Copper sulfide of the formula Cu.sub.xS.sub.y, wherein x and y are integer or non-integer values, wherein (i) the copper sulfide has a sulfur 2p XPS spectrum with peaks at 162.3 eV (1 ev), 163.8 eV (1 ev) and 68.5 eV (1 ev), characterised in that the peak at 168.5 eV has a lower value of counts per second (CPS) than both the peak at 162.3 eV and the peak at 163.8 eV; and (ii) the copper sulfide has a copper 2p XPS spectrum with peaks at 932.0 eV (2ev) and 933.6 eV (3eV) and characterised in that the XPS spectrum does not comprise identifiable satellite peaks at 939.8 eV and 943.1 eV (3 eV).

Copper sulfide of the formula Cu.sub.xS.sub.y, wherein x and y are integer or non-integer values, wherein (i) the copper sulfide has a sulfur 2p XPS spectrum with peaks at 162.3 eV (1 ev), 163.8 eV (1 ev) and 68.5 eV (1 ev), characterised in that the peak at 168.5 eV has a lower value of counts per second (CPS) than both the peak at 162.3 eV and the peak at 163.8 eV; and (ii) the copper sulfide has a copper 2p XPS spectrum with peaks at 932.0 eV (2ev) and 933.6 eV (3eV) and characterised in that the XPS spectrum does not comprise identifiable satellite peaks at 939.8 eV and 943.1 eV (3 eV).

Provided is a method for separating copper from nickel and cobalt with which it is possible to selectively and efficiently separate copper, as well as nickel and cobalt, from an alloy including copper, nickel, and cobalt such as an alloy having high corrosion resistance that includes copper, nickel, and cobalt obtained by dry treatment of waste lithium ion cells. An alloy including copper, nickel, and cobalt is brought into contact with sulfuric acid in the joint presence of a sulfurizing agent, and a solid containing copper and a leachate containing nickel and cobalt are obtained.

Provided is a method for separating copper from nickel and cobalt with which it is possible to selectively and efficiently separate copper, as well as nickel and cobalt, from an alloy including copper, nickel, and cobalt such as an alloy having high corrosion resistance that includes copper, nickel, and cobalt obtained by dry treatment of waste lithium ion cells. An alloy including copper, nickel, and cobalt is brought into contact with sulfuric acid in the joint presence of a sulfurizing agent, and a solid containing copper and a leachate containing nickel and cobalt are obtained.

The present invention seeks to provide cadmium-free quantum dots with a narrow fluorescence FWHM. The quantum dot does not contain cadmium and its fluorescence FWHM is 30 nm or less. The quantum dot is preferably a nanocrystal containing zinc and tellurium or zinc and tellurium and sulfur or zinc and tellurium and selenium and sulfur. Further, the quantum dot preferably has a core-shell structure in which the nanocrystal serves as a core and the surface of the core is coated with a shell.

The present disclosure relates to a sodium-ion storage material and an electrode material for a sodium-ion battery, an electrode material for a seawater battery, an electrode for a sodium-ion battery, an electrode for a seawater battery, a sodium-ion battery, and a seawater battery, which include the sodium-ion storage material. Specifically, the sodium-ion storage material may include one or more materials selected from the group consisting of Cu.sub.xS, FeS, FeS.sub.2, Ni.sub.3S, NbS.sub.2, SbO.sub.x, SbS.sub.x, SnS and SnS.sub.2, wherein 0<x2. When the sodium-ion storage material according to the present disclosure is used, it may exhibit high discharge capacity, and when the sodium-ion storage material is applied to a sodium-ion battery which is a secondary battery, it may exhibit excellent charge/discharge cycle characteristics.