New characterisation strategy proves promising in high-purity metal separation

Metals with similar chemical properties are usually extracted together, which limits the opportunities to separate high-purity metals. To increase those opportunities, it's important to understand how different metal species act during the solvent extraction process.

Researchers from the Institute of Process Engineering (IPE), of the Chinese Academy of Sciences, have developed a new strategy to characterise polymeric transition metal species in acidic solution, which may help to separate those high-purity metals.

Their study, which was published in the KeAi journal Green Chemical Engineering (GreenChE) employed a high-resolution electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) in the characterisation strategy. This was used to measure metal species in aqueous solution, and the corresponding data was analyzed semi-quantitatively.

Using this method, the researchers visualised the transformation evolutions of vanadium (V) species, chromium (Cr) species, tungsten (W) species and molybdenum (Mo) species.

"We can use this facile method to investigate the hydrolysis evolutions of polymeric metal species systematically," said Pengge Ning, a principal investigator at IPE.

The researchers described the formation and polymerization of the four metals (V, Cr, W and Mo) by this method. The obtained species distribution can guide the appropriate reaction conditions for high-purity metal separation. They realised the production of 99.9% high-purity vanadium under 100L/h pilot-scale.

"This work is promising in metal chemical speciation characterisation even for Ni, Co, and REE metals," said Ning, "it will guide further development of high-purity metal recovery."

This news item is based on a press release that appeared on the Chinese Academy of Sciences website.

Contact the corresponding author: Pengge Ning pgning@ipe.ac.cn