Advancing electrified CO2 capture: Material design strategies for magnetic adsorption composites

This study investigates the design and performance of magnetic adsorption composites (MACs) for application in electrified CO 2 capture with temperature swing adsorption from point sources. The MACs were composed of Fe 3 O 4 as magnetic component to act as inductive heating source and zeolite 13× as a CO 2 adsorbent. Three MAC configurations were prepared and evaluated under temperature feedback-loop control at different desorption temperatures ranging between 100 − 150 ° C : Homogeneous mixture of Fe 3 O 4 and zeolite 13×, a core-shell structure with magnetic Fe 3 O 4 core and zeolite 13× shell, and a mixed bed configuration containing separate heating and adsorbent beads. Resistive wall heated and room-temperature desorption experiments were conducted as references. In average, the heating experiments reached a steady-state effective working capacity after around 20 adsorption-desorption cycles. The homogenous mixture exhibited the most favorable performance, combining fast heating response, stable temperature control, and high CO 2 desorption efficiency. When reaching steady state, it achieved 99 % desorption within 94 s and the highest productivity of 0.52 m g C O 2 g MAC ∙ s with a theoretical regeneration energy of 3.0 MJ k g C O 2 . The core-shell structure showed limited temperature control due to low heat transfer through the shell, while the mixed bed configuration achieved moderate performance. Compared with column wall heating, inductive heating improved thermal efficiency by delivering heat directly to the adsorbent region. However, efficient coupling of the magnetic field to the magnetic material remains the key challenge for energy efficient induction heated TSA. • Three different magnetic adsorption composite configurations were synthesized with constant bead size and mass fractions from commercial materials. • Desorption by column-wall heating was tested for comparison. • Adsorption-desorption cycles were conducted until steady-state was reached. • Induction heating strategies showed to desorb faster and more efficient than conventional desorption. • Homogeneous magnetic adsorbent composites had the lowest regeneration energy of 2.91 MJ k g C O 2 with a productivity of 0.52 m g C O 2 g MAC s .