A photograph of a researcher wearing a white lab coat conducting ionic liquid experiments in a laboratory setting.

A researcher conducting ionic liquid experiments.

Ionic liquids for metal production

Ionic liquids are salts that exist in the liquid form at, or near, room temperature.

  • 11 March 2010 | Updated 14 October 2011

The scientific and commercial interest in ionic liquids is growing rapidly because they are tuneable media and can be tailored to suit the applications of interest, which includes catalysis, synthesis and electrochemistry.

Since ionic liquids are comprised of charged particles (a cation and an anion) that are mobile, they can conduct electricity.

Accordingly, this makes them good electrolytes for electrochemical applications such as electrowinning, electroplating and electrorefining.

Ionic liquids have a higher electrochemical stability than water and organic solvents.

Ionic liquids also have a higher electrochemical stability than water and organic solvents which allows the electrodeposition of metals which are impossible or difficult to obtain from more traditional solvents.

Commercial electrowinning of aluminium is energy intensive as it is conducted at nearly 1000 °C. 

Ionic liquids have the capacity to significantly reduce the operating temperature of the process, improving energy efficiency.

Other electrochemical processes can be made greener by replacing the volatile organic solvents with less volatile and non-flammable ionic liquids.

Clearly the properties of ionic liquids also have occupational health and safety benefits.

A black and white scanning electron micrograph showing a fractured aluminium deposit obtained from an ionic liquid solution at 80 °C.

A fractured aluminum deposit obtained from an ionic liquid solution at 80 °C.

Electrodeposition in ionic liquids for metal production and high quality coatings is a key focus for the Process Science and Engineering division.

Besides the apparent advantages of ionic liquids, ionic liquids and the processes that occur in them are yet to be fully understood.

Our studies attempt to address the knowledge gaps in order to facilitate the development of commercial applications.

Current research focus

Our research is directed towards understanding:

  • the fundamentals of electrochemistry in ionic liquids
  • impact of impurities such as water on electrodeposition
  • solution chemistry in ionic liquids
  • structure of ionic liquids in the bulk and at the electrode interface
  • structure-property relationship in ionic liquids
  • scale-up of electrodeposition in ionic liquids.

Read about ionic liquids research leader Dr Theo Rodopoulos: researching energy-efficient technologies for the aluminium industry.