Fraunhofer develops membrane reactor for low-emission lime production

Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS are developing a new membrane reactor technology aimed at enabling climate-neutral lime production while simultaneously creating new raw materials. The construction materials industry is a significant contributor to global greenhouse gas emissions, with the production of lime and cement being particularly carbon-intensive.

The traditional calcination process for lime releases substantial amounts of carbon dioxide, necessitating innovative solutions for emission reduction. The Fraunhofer team's approach captures this CO2 instead of releasing it. Using green hydrogen, the captured carbon dioxide is converted into methane through a catalytic process.

This methane is then subjected to pyrolysis, splitting it into hydrogen and valuable elemental carbon (carbon black). The hydrogen is recycled back into the process, while the carbon black can be utilized in industries such as chemical manufacturing or as agricultural fertilizer. This Carbon Capture and Utilization (CCU) technology offers a promising pathway to significantly reduce the environmental footprint of the building materials sector.

The researchers aim for broader recognition of their technology among policymakers, arguing that utilizing carbon within a circular economy is as crucial as storing it. The membrane reactor principle has been successfully tested in collaboration with partners, with the next phase involving the scaling of the technology for industrial application.