GlyLeach is an alkaline-based process that effectively leaches all copper minerals except Chrysocolla – a copper silicate mineral – using glycine as a major reagent. 

The process can also leach gold when the temperature of the glycine is raised to 60C, providing a non-toxic alternative for the gold industry.

MPS said glycine was the simplest and cheapest of amino acids and provided significant environmental advantages over any other copper or gold lixiviant.

Examples include its biodegradability, its ability to enhance solubility of copper ions in aqueous solutions, and its capacity for recovery and recycling. 

Apart from normal process losses – usually expected to be less than 5% – MPS said more than 99% of the glycine was recoverable.

Curtin process inventor professor Jacques Eksteen said GlyLeach could make a wide impact across copper and gold operations.

“The process has a number of immediate applications including leaching of low grade ores, differentially leaching of copper and gold ores, upgrading concentrates and tailings retreatment,” he said.

MPS technical director Frank Trask said GlyLeach required no new equipment to be designed, had low operating costs due to regeneration of the principal reagents and was expected to provide high copper recoveries with almost all copper minerals, even chalcopyrite.

Its GlyLeach rights cover Australasia, North and South American and Asia, with options to expand to other countries upon satisfying agreed criteria.

MPS also has exclusive Australasian rights to the Continuous Vat Leaching, a Canadian developed mechanical leaching process.

It is expected the two technologies will be synergistic for a range of deposits.

Both technologies can be supported by MPS at its facility at CSIRO’s Australian Mineral Research Centre and agencies located in Canada and Chile.