Induction Heated Catalytic Reactions: Exploring Magnetic Particles and Their Use in the Green Transition

The implementation of renewable energy has driven a sharp decline in renewable energy costs, creating opportunities to replace fossil-fueled heating in catalytic processes with electrically powered alternatives. One promising approach is induction heating. Magnetic particles (susceptors) dissipate power in an alternating magnetic field, thus providing heat directly to the catalyst bed. This localized heating minimizes thermal losses, provides a homogeneous temperature profile, and enables rapid response. This could allow for flexible operation under intermittent renewable energy supply.

This PhD thesis focuses on the development, understanding, and application of magnetic particles for induction heated catalytic reactions. The work involved the development and use of several experimental techniques: in situ vibrating sample magnetometer, calorimetry, AC magnetometer, and X-ray diffraction. The bulk of this work is presented in the attached publications.

A universal susceptor was developed based on the preferential oxidation of aluminum in a Co-Al alloy, forming a protective shell of alumina around a magnetic cobalt core that is able to deliver heat without interacting with the chemical environment. The susceptor demonstrated great performance and stability under the steam methane reforming process.

Additionally, an ammonia decomposition reactor was constructed to operate under both induction and conventional heating, enabling comparative studies between the two heating modes. Contrary to some literature reports, no catalytic enhancement from induction heating was observed. Optimized Co-catalysts had low power dissipation due to the low metal loading and small particle size (<10 nm). Mixing with the universal Co-Al susceptor greatly improved efficiency and exhibit fast start-up times, confirming its potential for flexible operation.

Overall, this work advances the understanding of induction heated catalytic systems and demonstrates strategies for designing magnetic particles with high heating efficiency.