Project description
Boosting the recovery of precious metals
Electronic waste, consisting of discarded electrical or electronic devices, is a growing concern worldwide. It contains many components, including precious metals (PMs) that are steadily becoming more abundant than natural ore deposits. PMs are of great economic value mainly due to their rarity, which is why much effort has been placed into their recovery through urban mining. The EU-funded IONIC BARRIER project aims to design internal pH-driven ionic barrier-based protocols in order to enhance the recovery and separation of PMs from urban mines. To achieve this, the project will use the properties and advantages of adsorption and hydroxide precipitation.
Objective
Precious metals (PMs) including Au, Pd, Pt are naturally occurring elements of high economic values. However, they face future supply-chain risks due to their limited abundance in the earth’s crust. Meanwhile, frequent replacements of electrical and electronic devices are leading to accumulated amounts of e-wastes, with PM contents gradually superseding natural ore deposits. Urban mining is the act of recovering PMs from e-wastes. This technique is important from economic and environmental remediation viewpoints, owing to the prospects of generating income through recycling and protecting the environment from pollution dangers. This proposal aims to utilize the properties and advantages of adsorption and hydroxide precipitation to design internal pH-driven ionic barrier-based protocols to recover PMs from urban mines (e-wastes). The proposed techniques will involve the fabrication of polyelectrolyte complex (PEC) capsules using poly(diallyldimethylammonium), PDADMA and poly(styrenesulfonate), PSS. Here, a new concept of “ionic barrier” will be combined with metal-hydroxide formation to help retain high internal pH within the PEC capsules. The capsules will create ionic barriers that will promote selective passage of PMs and reject heavy metals such as Cd, Pb, Hg etc., whilst the high internal pH will induce hydrolysis and metal hydroxide formation between OH ions and the penetrated PMs within the capsules. For further improvement of the recovery efficiency, the functional polymer, polyethyleneimine (PEI) will be immobilized. Strategic recovery techniques will be designed via sequential desorption and adsorption-coupled incineration to obtain elemental PMs. Consequently, these protocols are expected to enhance separation and recovery of PMs, and eliminate the hydroxide sludge and sulfide gases that usually accompany the precipitation process. Moreover, it will help to salvage the supply-chain risk associated with PMs, and keep their continuous supply to industries.
Fields of science
Programme(s)
Funding Scheme
MSCA-IF-EF-ST - Standard EFCoordinator
53850 Lappeenranta
Finland