(329a) 3D-Printed Dual Functional Adsorbent Catalyst Monoliths for Combined CO2 Capture and Ethane Dehydrogenation

Adsorptive and catalytic processes occur in different beds because most CO₂ adsorbents capture perform best at 25 ºC, whereas most oxidative dehydrogenation reactions occur between 500-700 ºC. One way of utilizing CO₂ is as a light oxidant in dehydrogenation reactions over heterogeneous catalysts.^[1] Combining adsorption and catalysis in a single bed is advantageous because it can reduce heating and cooling times, lower energy consumptions, and enhance product throughput. Nevertheless, the composite materials should be formed into practical contactors to reduce pressure drops, mitigate particle scattering, and enhance heat and mass transfer. We recently reported a novel approach to structure composite oxide/ZSM-5 heterogeneous catalysts by direct 3D-printing of commercial oxide/zeolite inks.^[2] In this study we applied our 3D printing technique to CaO-oxide/ZSM-5 inks to produce the first-ever adsorbent/catalyst monoliths. Metal screening was performed over nine composite catalysts (Ga, In, Mo, Cr, V, Ce, Ti, Ni, and CaO/ZSM-5) to determine which material(s) perform best for combined CO₂ adsorption and ethane dehydrogenation. Combined adsorption/catalysis experiments revealed that the V₂O₅-CaO/ZSM-5 sample had the best overall performance, achieving 65% conversion of CO₂, 36.5% ethane conversion, and 98% ethylene selectivity. This performance is the highest ever reported for combined CO₂ adsorption/dehydrogenation reaction, representing a fundamental advancement in the areas of CO₂ utilization, paraffin dehydrogenation, and material science.

References

[1] A. Al-mamoori et al. Appl. Catal. B Environ. 2020, 278, 119329.

[2] S. Lawson et al. Adv. Sustain. Syst. 2020, 5, 1.