The project

The MECALO project seeks to transform the EU's metallurgical industry by using renewable hydrogen to indirectly replace fossil carbon in producing critical raw materials like silicon (Si) and manganese (Mn).
By capturing and reusing carbon oxides from process off-gases, MECALO enables CO2-neutral metal production without needing to overhaul the core processes. This innovative approach is key to meeting the EU’s growing demand for Si and Mn, essential for clean energy technologies, while bolstering the EU’s resilience and sustainability in raw material supply. The project aligns with the European Critical Raw Materials Act and supports the EU’s 2050 climate-neutrality goal.
5 Strategic Objectives


Off-gas conversion
Optimize gas conversion to turn carbon oxides in off-gases into solid carbon using renewable hydrogen and plasmalysis.

H2-looped C feedstock synthesis
Establish a process to convert looped carbon into a raw material suitable for reducing metal oxides.

Metal production
Demonstrate renewable hydrogen in Si and Mn production by validating H₂-looped carbon for metal production under
industrial conditions.

Digitalization
Ensure optimal energy and material efficiency in both stable and variable renewable hydrogen
and electricity supply using
advanced digital tools.

Business case
Maximize the potential for industrial application and further exploitation of project results.
The Process
MECALO will develop a production pathway in which renewable hydrogen indirectly replaces fossil carbon reductants.
The carbon oxides in the process off-gases are captured and converted into solid carbon using renewable hydrogen, which is then reused as a reduction material in metal production.

This approach will eliminate the use of carbon as external feedstock in the carbothermic production.
METHANATION
Exhaust gases from metal production, rich in carbon oxides, are repurposed for methane production instead of being released into the atmosphere.
Methane, rather than serving as an energy source, acts as a “carbon bearer” in the transformation of climate-harming CO₂ into reusable carbon feedstock. In the presence of a catalyst, carbon oxides react with hydrogen to form methane. About half of the hydrogen comes from sustainable external sources, while the rest is a by-product of the plasmalysis process.
Methane PYROLYSIS
Methane undergoes microwave plasma cracking ("Plasmalysis") to produce solid carbon powder and hydrogen.
The plasma provides intense thermal and electromagnetic energy, breaking methane into its fundamental components. The generated hydrogen is recycled into the methanation unit for new methane synthesis, while the carbon powder is processed into raw material for metal production.
Raw materials synthesis
We have converted CO₂ into solid carbon, but in the form of fine powder, which is unsuitable for metal production.
The innovation lies in transforming this powder into a usable raw material through an advanced treatment that aggregates it into larger lumps using bio-binders. This fossil-free process creates a compact material for further processing, enabling the reuse of what would have been CO₂ emissions while reducing the need for external raw materials like coal and coke.
Carborthermic reduction
The final step is to demonstrate metal production using the synthesized raw materials in existing furnaces through carbothermal reduction.
What makes this system unique is the elimination of external carbon reductants, such as hard coal or coke, by relying solely on internally recycled carbon. This closed-loop approach reduces dependence on non-renewable resources and minimizes environmental impact, ensuring that carbon is continuously recovered and reused within the production cycle.