The Future of Scandium Recovery from Wastes

Olga Chernoburova,Alexandre Chagnes

doi:10.3390/materproc2021005055

Olga Chernoburova, Alexandre Chagnes

Open Access

https://doi.org/10.3390/materproc2021005055

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Abstract

With growing demand for renewable and clean energy technologies, the need in rare earth metals is increasing. Scandium, which is often considered a rare earth element (REE), is a critical metal mainly used in solid oxide fuel cells (SOFCs) and high strength aluminum alloys used in aerospace and 3D printing applications. Furthermore, scandium supply is limited due to its scarcity and the high cost of its production in Asia and Russia while Europe has no production of scandium. Therefore, scandium extraction from alternative resources such as secondary resources located in Europe is of great concern. Within this context, this work provides a condensed state-of-art review of the issue of scandium recovery from industrial wastes. Priority was given to addressing the technological and economic challenges associated with the recovery of scandium from the said residues, with particular emphasis on the bauxite residue from alumina production, which represents nearly 5 million tons on dry basis per year in Europe.

Highlights

Scandium is a transition metal mostly used in a developing technology of solid oxide fuel cells (SOFCs) and Sc-Al alloys
In the year of 2017, scandium entered the list of critical raw materials (CRMs), assessed separately from the rest of rare earth elements (REEs)
There are several options, for example, scandium can be replaced by yttrium in SOFCs and by titanium and lithium in Sc-Al alloys

Summary

Introduction

Scandium is a transition metal mostly used in a developing technology of solid oxide fuel cells (SOFCs) and Sc-Al alloys. There are several options, for example, scandium can be replaced by yttrium in SOFCs and by titanium and lithium in Sc-Al alloys. It has to be noted, that yttrium, titanium, and lithium all belong to CRMs as well [4]. One possible way of avoiding a potential supply disruption of scandium is finding alternative sources. Secondary sources, such as some industrial residues, present a promising potential for scandium recovery. Despite the attractive concentrations and large available tonnages of these residues, the extraction of scandium from them presents significant technological and economic challenges

Background

Bauxite Residue

Coal Ash

Findings

Conclusions