Rare Earth elementsPrecious metal recovery technique ideal for rare Earth elements purification

Published 7 March 2013

Researchers have come up with a new approach to make the recovery of high value precious metals faster and more economically viable. The new technique could be ideal for the purification of rare earth elements, which are vital commodities for ‘green’ technologies such as hybrid cars and novel batteries.

Murdoch University researchers have come up with a new approach to make the recovery of high value precious metals faster and more economically viable.

Dr. Chun-Yang Yin and Dr. Aleksandar Nikoloski said the rising cost of metals such as platinum and palladium made recovery economically and environmentally vital.

A Murdoch University release reports that their technique — which was trialed by extracting platinum and palladium from a spent automotive catalyst leach solution — has shown major advantages over conventional methods.

“Traditional mineral extraction uses a time-consuming two-stage process which sees a mineral leach solution and an extractant vigorously mixed before being transferred to a settler,” Yin said.

“The new microfluidics approach is a single-stage process which sees the leach solution and extractant pumped along two very fine micro-channels embedded in a PYREX microchip.

“This nano-level interplay results in increased surface-to-volume ratio and improved metal ion transfer, with 99 per cent of extraction occurring within a single second.

“This really could transform the purification technology for platinum group metals and the niche minerals industry.”

Yin said the new technique would not only speed up processing, but would allow companies to significantly reduce plant space as compared to traditional methods.

“Microfluidics is an emerging area of science – and our innovations represent an excellent opportunity for Australian researchers and companies to gain a foothold in the area,” he said.

“Up until now microfluidics has been used primarily in the medical and pharmaceutical industries, and has never been applied to industrial mineral processing. We’re one of only a very few groups in the world working in this area.”

Yin said the findings represented proof-of-concept and that his group was now interested in partnering with industry to scale up.

He added that the new technique could be ideal for the purification of rare earth elements, which are vital commodities for ‘green’ technologies such as hybrid cars and novel batteries.

— Read more in Chun-Yang Yin et al., “Microfluidic solvent extraction of platinum and palladium from a chloride leach solution using Alamine 336,” Minerals Engineering 45 (May 2013): 18–21 (doi:org/10.1016/j.mineng.2013.01.013)