Is Copper Cathode Pure Copper?
Yes, copper cathode is very pure copper, typically 99.99% or more copper by weight.
Copper cathode is copper in its highly purified state, typically containing at least 99.99% copper by weight. It has a variety of uses and applications:
Production Process
- Copper cathode is produced through a process called electrorefining. In this process, impure copper anodes are suspended in an electrolytic cell containing a copper sulfate and sulfuric acid solution.
- When electric current is passed through the cell, pure copper from the anodes is dissolved into the electrolyte and deposited onto stainless steel blanks at the cathode. Impurities then fall to the bottom of the cell as anode slimes.
- The end result is nearly pure copper cathode sheets that are removed from the stainless steel blanks. They are then rinsed, bundled and packaged for shipment to downstream manufacturers.
Properties
- Copper cathode has a reddish-orange color and metallic luster. It is highly malleable and ductile.
- It has excellent thermal and electrical conductivity, only second to silver. It also has good corrosion resistance.
- The purity of copper cathode is typically above 99.99% copper. Oxygen-free high conductivity (OFHC) grade may be 99.99% copper and higher.
- Key residual impurities can include silver, gold, nickel, iron, sulfur and oxygen. But these are usually only present in trace amounts measured in parts per million.
- High purity copper cathode has excellent formability, ductility and conductivity for making copper products.
Global Production
- Major producers of copper cathode include Chile, Peru, China, USA, Australia, Russia, Canada and Zambia. Chile alone produces over 5.5 million metric tons per year.
- The quality and purity of cathode varies based on the refining techniques and source ore used by different producers around the world.
- Globally about 25 million tons of copper cathode are produced per year. It is traded internationally as a commodity by major merchants and exchanges.
Applications
- A primary use of copper cathode is to manufacture tubes, rods, wires and other copper products by processes like extrusion, drawing and rolling.
- It is also used to produce copper alloys by melting with other elements. Brass and bronze are some prominent copper alloys.
- In electrical applications, copper cathode is made into bus bars, power cables, electrical contacts and other components. Its high conductivity is highly valued.
- Due to its excellent heat conductivity, it is made into heat exchangers for HVAC and refrigeration equipment.
- Electronics industry uses high purity copper cathode for making printed circuit boards, semiconductor chips and other devices.
- Building construction utilizes copper cathode in power distribution, switches, roofing and plumbing applications.
- Other uses include high tech superconducting magnets, antimicrobial applications, cookware and sculpture artworks.
Trade and Pricing
- Copper cathode trading involves miners, merchants, commodity exchanges, manufacturers and other parties. Contracts specify cathode grade, quantity and shipment terms.
- Pricing is based on the latest London Metal Exchange (LME) cash settlement price plus a producer premium per ton. This premium accounts for cathode quality and processing cost.
- The LME copper cash price fluctuates daily based on global demand-supply dynamics. Copper prices reached record highs in 2022 due to strong demand and tight supply.
- Major merchant suppliers of copper cathode include Trafigura, Glencore and Freeport McMoRan. Cathode is shipped in bundles or cargo lots to downstream manufacturers.
In summary, copper cathode represents the highly refined form of copper produced by electrorefining. With 99.99%+ purity, excellent conductivity and formability, it provides a clean material for making high-performance copper products. It is a globally traded commodity with pricing reflecting latest supply and demand dynamics.