System and method for producing copper powder by electrowinning in a flow-through electrowinning cell
View Patent ↗This invention relates to a system and method for producing a metal powder product using conventional electrowinning chemistry (i.e., oxygen evolution at an anode) in a flow-through electrowinning cell. The present invention enables the production of high quality metal powders, including copper powder, from metal-containing solutions using conventional electrowinning processes and/or direct electrowinning.
1. A process for producing copper powder by electrowinning comprising the steps of:
introducing a copper-containing solution into a flow-through electrowinning cell;
electrowinning copper powder from said copper-containing solution to produce a slurry stream containing copper powder particles and electrolyte, wherein said step of electrowinning copper powder comprises producing oxygen gas at an anode and forming copper powder at a cathode, and wherein said electrowinning cell voltage is from about 1.5 V to about 3.0 V and said electrowinning cell current density is about from 10 to about 200 amperes per square foot of active cathode.
2. The process of claim 1 , further comprising the step of conditioning at least a portion of said slurry stream to remove contaminants and/or impurities contained in the residual entrained electrolyte.
3. The process of claim 1 , further comprising the step of drying the copper powder particles originally present in the slurry stream to produce a copper powder product.
4. The process of claim 1 , further comprising the step of subjecting said copper powder product to at least one of size classification, packaging, direct forming, casting, briquetting, extrusion or melting.
5. The process of claim 1 , further comprising the step of separating at least a portion of the coarse copper powder particles in said slurry stream from at least a portion of the fine copper powder particles in said slurry stream in a size classification stage.
6. The process of claim 1 , wherein the process further comprises operating said electrowinning cell at a cell voltage, wherein said cell voltage is less than about 2.0 Volts.
7. The process of claim 1 , further comprising the steps of
washing at least a portion of the copper powder particles in said slurry stream to produce a waste solution stream, and
separating at least a portion of said waste solution stream from said copper powder particles.
8. A process for producing copper powder by electrowinning consisting essentially of:
introducing a copper-containing solution into a flow-through electrowinning cell;
electrowinning copper powder from a copper-containing solution to produce a slurry stream containing copper powder particles and electrolyte, wherein said step of electrowinning copper powder comprises producing oxygen gas at an anode and forming copper powder at a cathode, and wherein said electrowinning cell voltage is from about 1.5 V to about 3.0 V and said electrowinning cell current density is about from 10 to about 200 amperes per square foot of active cathode;
optionally, separating at least a portion of the electrolyte from the copper powder particles in the slurry stream;
optionally, separating at least a portion of the coarse copper powder particles in said slurry stream from at least a portion of the fine copper powder particles in said slurry stream in a size classification stage;
conditioning at least a portion of said slurry stream;
optionally, separating at least a portion of the bulk liquid from the copper powder particles in said slurry stream;
optionally, drying at least a portion of the copper powder particles originally present in the slurry stream to produce a copper powder product; and
optionally, subjecting said copper powder product to at least one of size classification, packaging, direct forming, casting, briquetting, extrusion or melting.