High-performance hydrogen sulfide removal using CuO-impregnated carbon microstructures

Conventional gas adsorption technologies rely on granular activated carbon (GAC) beds, which inherently suffer from channeling, high pressure drop, and premature breakthrough. This work demonstrates the first use of additive manufacturing to create copper oxide (CuO) impregnated activated carbon microstructures (ACMs) with engineered channel geometries, marking a step-change in toxic gas capture. Impregnation yielded CuO and Cu2O phases uniformly distributed along channel walls, confirmed by PXRD, XPS, and SEM-EDX. Breakthrough testing with 500 ppm H2S in N2 showed effective chemisorption, with tessellated and two-dimensional helix geometries achieving breakthrough times up to 10.3 min g−1 and equilibrium capacities of 3.6 and 3.0 mg g−1, respectively. On a Cu-normalized basis, both structures achieved 45–73 mg H2S g−1 Cu with 8–14% Cu utilization, consistent with stateof-the-art impregnated carbons. Mechanistic analysis revealed early breakthrough followed the Bohart-Adams model (reaction-limited), while later stages were captured by a onedimensional axial diffusion model (mass transfer limited). These results demonstrate ACMs as efficient, tunable sorbents for toxic gas capture, and highlight the broader potential of engineered carbons for next-generation air filtration technologies.