A method is disclosed for manufacturing a cathode for electrolytic processes, the cathode comprising a conducting bar and a plate attached to the conducting bar, wherein the conducting bar has a conducting member attached thereto to increase the conductivity of the conducting bar.

A method for refining bismuth is provided, which comprises recovering bismuth from a solution obtained after recovery of noble metals from a copper electrolytic slime.

The method comprises:
1) a neutralization step of adding alkali to an acid solution to adjust the pH to the range of 2.0 or more and 3.0 or less, and then performing solid-liquid separation to obtain a neutralized filtrate and a neutralized precipitate;
2) an alkaline leaching step of adding alkali to the neutralized precipitate obtained in the neutralization step to separate the resultant into an alkali leachate and an alkaline leaching residue;
3) a sulfuric acid leaching step of adding sulfuric acid to the alkaline leaching residue to separate the resultant into a sulfuric acid leachate and a sulfuric acid-leaching residue;
4) a cooling step of cooling the sulfuric acid leachate obtained in the sulfuric acid leaching step to obtain crystals of bismuth sulfate;
5) a bismuth oxidation step of adding alkali to the crystals of bismuth sulfate obtained in the cooling step to obtain bismuth oxide; and
6) an electrolysis step of adding an acid solution to the bismuth oxide obtained in the bismuth oxidation step for dissolution and then electrowinning the thus obtained solution to obtain metal bismuth.

A hanger bar for an electrowinning cell, wherein hanger bar includes a bar portion and one or more contact portions adapted, in use, to be brought into contact with an electrical conductor. The contact portions are fabricated from an electrically conductive material, and a welded seal is formed between the bar portion and the contact portions in order to minimize corrosion.

A hanger bar for an electrowinning cell, wherein hanger bar includes a bar portion and one or more contact portions adapted, in use, to be brought into contact with an electrical conductor. The contact portions are fabricated from an electrically conductive material, and a welded seal is formed between the bar portion and the contact portions in order to minimize corrosion.

The invention relates to a new way of reducing dissolved metals, in particular Cu.sup.+2 to Cu.sup.0, in which the effect of the diffusion-limiting layer is regulated, optimising the variables which determine the mobilisation of the metal ion (Cu+.sup.2) towards the cathode and the thermodynamic stability of the reduction reaction of Cu+.sup.2 to Cu.sup.0 (or metal of interest) on the cathodic surface. The process is carried out by controlling a dimensionless ratio (referred to as t) or the cathodic polarisation, within certain predefined margins, dynamically adjusting concentrations, flows and/or electrical currents to maintain the predefined operating conditions at an optimum level.

The invention relates to a new way of reducing dissolved metals, in particular Cu.sup.+2 to Cu.sup.0, in which the effect of the diffusion-limiting layer is regulated, optimising the variables which determine the mobilisation of the metal ion (Cu+.sup.2) towards the cathode and the thermodynamic stability of the reduction reaction of Cu+.sup.2 to Cu.sup.0 (or metal of interest) on the cathodic surface. The process is carried out by controlling a dimensionless ratio (referred to as t) or the cathodic polarisation, within certain predefined margins, dynamically adjusting concentrations, flows and/or electrical currents to maintain the predefined operating conditions at an optimum level.

The present disclosure relates to an electrochemical flow reactor, such as a continuous flow electrochemical tubular reactor. This disclosure also relates to processes, systems, and methods comprising an electrochemical flow reactor. An electrochemical flow cell can comprise a reaction chamber, a first static mixer electrode, a second counter electrode, and a separator disposed between the first and second electrodes.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

This application pertains to methods of recovering metals from metal sulfides that involve contacting the metal sulfide with an acidic sulfate solution containing ferric sulfate and a reagent that has a thiocarbonyl functional group, wherein the concentration of reagent in the acidic sulfate solution is sufficient to increase the rate of metal ion extraction relative to an acidic sulfate solution that does not contain the reagent, to produce a pregnant solution containing the metal ions.

A method of recovering metals from electronic waste comprises providing a powder comprising electronic waste in at least a first reactor and a second reactor and providing an electrolyte comprising at least ferric ions in an electrochemical cell in fluid communication with the first reactor and the second reactor. The method further includes contacting the powders within the first reactor and the second reactor with the electrolyte to dissolve at least one base metal from each reactor into the electrolyte and reduce at least some of the ferric ions to ferrous ions. The ferrous ions are oxidized at an anode of the electrochemical cell to regenerate the ferric ions. The powder within the second reactor comprises a higher weight percent of the at least one base metal than the powder in the first reactor. Additional methods of recovering metals from electronic waste are also described, as well as an apparatus of recovering metals from electronic waste.