Practical trainings, student assistants and theses

Mineral carbonation is a promising method for permanent CO₂ storage, particularly relevant to the cement industry, which accounts for about 8% of anthropogenic emissions[1]. In this process, CO₂ is transformed into stable carbonates using calcium- and magnesium-rich minerals. Wollastonite (CaSiO₃) is preferred for its higher reactivity compared to Mg-silicates.

CaSiO₃ + CO₂ → CaCO₃ + SiO₂

Wet carbonation in a three-phase reactor involves CO₂ dissolution, mineral leaching, and carbonate precipitation[2]. The main challenges are slow kinetics and low energy efficiency, requiring optimization of reactor design and operating parameters. Fluid dynamics analysis is essential to enhance mass transfer between CO₂ bubbles and solid particles.

To this end, the study aims to investigate how the reactor’s operating parameters—including temperature, solid loading, stirring rate, and CO₂ flow rate—affect the amount of CO₂ absorbed by the material (CO₂ uptake).

Objectives of the experimental campaign:

• Carbonation experiments on wollastonite under varying operating conditions in a 6 L stirred tank reactor.
• CO₂ uptake measurements of collected samples using a calcimeter.
• Data analysis and optimization of the operating conditions.

[1] A. A. Olajire, “A review of mineral carbonation technology in sequestration of CO2,” J. Pet. Sci. Eng., vol. 109, pp. 364–392, Sept. 2013, doi: 10.1016/j.petrol.2013.03.013.
[2] W. Ding, L. Fu, J. Ouyang, and H. Yang, “CO2 mineral sequestration by wollastonite carbonation,” Phys. Chem. Miner., vol. 41, no. 7, Art. no. 7, July 2014, doi: 10.1007/s00269-014-0659-z.

• Field of study: Process engineering, chemical engineering, mechanical engineering, fluid mechanics, physics or similar orientation
• Advantageous are experiences in laboratory work, evaluation of measurement data (e.g. programming skills) and chemical lab experience
• Ability for practical, accurate and independent work
• Good language skills in English

• Place of work: HZDR
• Start: from April 2026
• Duration: min. 3 months
• Remuneration according to HZDR internal regulations