Anna Siekierka, PhD, DSc, Eng, Associate Professor at the Faculty of Chemistry, has been awarded the prestigious grant by the European Research Council. Her project was selected from over 4,000 entries submitted by researchers from all parts of Europe. Prof. Siekierka will work on the ReHeal4waste project, aiming to extract valuable raw materials from used battery solutions while recovering energy and producing hydrogen.

The ERC Starting Grant is one of the most prestigious international grant programmes, under which young scientists (2 to 7 years after obtaining their PhD degree) with outstanding achievements and ideas for their own ambitious scientific projects can apply for funding for their research.

Wrocław Tech’s second such grant

This year, the European Research Council received over 4,000 applications from scientists across the continent. Grants were awarded to 483 entrants. For the second time in the history of our university, one of the winners is a researcher from Wrocław University of Science and Technology.

 Anna Siekierka, Associate Professor at the Faculty of Chemistry, was awarded 1.5 million EUR for the project named “Reverse salinity energy harvesting-assisted electromembrane system for metal ion fractionation and hydrogen production from battery waste” (acronym: ReHeal4waste).

The first winner of the grant hailing from our university was Łukasz Sterczewski, PhD, Eng, who received it in 2023.

Resource, not waste

Associate Professor Siekierka’s project concerns battery recycling – specifically, the separation of valuable raw materials from the solution produced after the hydrometallurgical processing of used batteries.

Such solutions are mixtures of cations of various metals, including lithium, cobalt, nickel, manganese, copper, and iron. Many of them are so-called strategic critical raw materials, that is, those whose resources are limited and for which demand is growing, as their use is crucial to the economy and our daily lives. We use them to manufacture products such as electronic components, electric vehicles, aeroplanes, mobile phones, and in medicine.

The mixture of these cations is difficult to separate, but it is worth the effort due to the high content of valuable raw materials and the need to find alternatives to obtaining them from mines. For comparison, a single battery contains 5 to 7 per cent lithium, while brine (the only potential source of lithium in our country) contains tenths of a per cent.

The international organisation Transport & Environment has even calculated (data as of December 2024) that used batteries and waste products from European car battery factories – once recycled – could meet 14% of the total demand for lithium, 16% for nickel, 17% of manganese and a quarter of cobalt demand in the production of such batteries – as soon as by 2030.

“Of course, there are already methods in industry for separating metals from used batteries and accumulators, but the search continues for technologies that are more environmentally friendly and economical,” says Associate Professor Anna Siekierka. “All the more so since the production of electric cars is increasing, and therefore the number of used batteries will also go up. Over time, the problem of managing them will grow, so they should be seen as a source of raw materials rather than waste.”

Inconspicuous membranes with immense potential

The core of Associate Professor Siekierka's project are cation exchange membranes – inconspicuous-looking polymer structures that have been appropriately functionalised. They are as thin as a sheet of paper and may resemble a piece of foil or the skin that forms on cocoa. Although their form is quite modest, their potential is enormous.

The task of the group of scientists that our researcher will set up will be to develop membranes that will transport only cations of specific metals (e.g. cobalt, nickel or manganese), i.e. separate them from a multi-component solution obtained from used batteries. Importantly, such membranes will be reusable (with a target service life of at least 2 years and up to 5 years – so that their use is economically justified).

The researchers will construct a specially designed membrane stack in which they will perform reverse electrodialysis (RED). To generate the energy needed to power the process, they will use the difference in electrical potential between the external electrodes, which occurs when two solutions with different salinity levels are mixed – i.e. a solution from used batteries and so-called permeate (low-concentration acid).

The production of hydrogen and oxygen will be an additional outcome of the entire process.

Five years of research

“Our project involves very demanding basic research,” says Associate Professor Siekierka. “Our work will include developing the structure of membranes and the method of their production, which involves work on the chemical compounds needed to make them. Also, we will determine the conditions under which they will degrade as well as model the flows between membranes. Moreover, we will work on the efficiency of the process itself.

 Associate Professor Siekierka will invite a few researchers to her team, including a physicist and an organic chemist. The project will also provide an opportunity to pursue doctoral thesis topics, and students will also gain experience and skills while contributing to it.

The research will last five years, and its outcomes will include a developed procedure for separating metal cations from solution, a library of information on compounds used in membrane production (in terms of their selectivity) and flow patterns in membrane stacks – i.e. detailed information that will enable further research aimed at commercialising the solution in the future.

 Associate Professor Anna Siekierka works at the Department of Process Engineering and Polymer and Carbon Materials Technology at the Faculty of Chemistry, Wrocław University of Science and Technology. She defended her doctoral thesis with honours in 2019. Additionally, she completed two placements at foreign centres: Deakin University and Technical University of Liberec.

Her main scientific interest is electromembrane processes used for selective separation of metal ions and energy recovery. She specialises in obtaining selective membranes and sorbents. She has been recognised for her achievements by institutions and bodies including the Ministry of Education and Science (Outstanding Young Scientist) and the Foundation for Polish Science (Start).