4.10.2019 Rubidium required for quantum computers can be recovered from power plant fly ash (Nygrén)
In her doctoral dissertation at the Ģֱ Enni Nygrén developed a method for recovering rubidium from power plant fly ash in co-operation with Jyväskylän Energia Oy. The work is part of a wider fly ash recovery process, where rare earth and precious metals are recovered from ashes, and now also rubidium.
Rubidium is a rare alkali metal that is currently low in use and mainly focused on research. However, demand for rubidium is expected to increase in the near future, as rubidium is one of the basic components of quantum mechanics based quantum computers that are under development. For this reason, the US Department of Energy has also listed rubidium as a critical element that needs to be secured in the future.
Fly ash is waste material from incineration power plants that is generated hundreds of thousands of tons a year in Finland. Fly ash has traditionally been used in soil improvement, roadbeds and concrete making, but recently fly ash has been found to be an excellent source of valuable elements.
Two recovery methods used
This study focuses on two recovery methods, where readily soluble metals (such as rubidium) were first leached from ash, and then rubidium was separated from other metals in the solution, either by liquid-liquid extraction or by solid ion exchange.
After optimizing the extraction parameters, 94 percent of the rubidium was recovered by liquid-liquid extraction while 99 percent of the other metals remained in the original solution. The 3D-printed resin used for ion exchange also effectively extracted rubidium, but rubidium’s removal from the resin was challenging and yields were low.
These results indicate that the use of fly ash as a raw material for rare metals could be economically viable when combining rubidium recovery with liquid-liquid extraction in addition to the recovery of other valuable metals.
The research was completed in Professor Ari Väisänen's research group and has been carried out in cooperation with Jyväskylän Energia Oy.
The study has been published in the JYU Dissertations series of doctoral dissertations of the Ģֱ. JYU Dissertations. ISSN 2489-9003; 136, ISBN 978-951-39-7852-5 (PDF). Link to publication:
FM Enni Nygrén's dissertation “Recovery of Rubidium from Power Plant Fly Ash” will be inspected on Friday 4th October at 12:00 pm in the YlistöKem4 lecture hall of the Department of Chemistry. The opponent is Professor Ulla Lassi (University of Oulu) and the custos is Professor Ari Väisänen (Ģֱ). The dissertation is in Finnish.
For more information:
M.Sc. Enni Nygrén, tel. (014) 260 1211, enni.k.nygren@jyu.fi
Communications Officer Tanja Heikkinen, tanja.s.heikkinen@jyu.fi, tel. +358 50 581 8351