Dispersion behavior of 3D-printed columns with homogeneous microstructures comprising differing element shapes

We used additive manufacturing (3D printing) to create ordered porous beds from a range of geometric shapes, including truncated icosahedra (approximating spheres), tetrahedral, octahedral, triangular bipyramid, and stellar octangular particles. We show that the printed porous media were highly reproducible and had excellent fidelity in physically reproducing computer-aided design models, with differences between designed and experimentally measured particle locations within ±0.5%, and within 1.3% in terms of bed porosity. Experimental residence time distributions were measured and the reduced plate height, h, was determined under different reduced velocities (Peclet number, Pe = 4-400). The results (using equivalent particle diameter to non-dimensionalize) show that, for the simple cubic (SC) arrangement, tetrahedral particles had a lower plate height (hmin = 1.56) than all other particle shapes tested, including spherical particles. We also, for the first time, experimentally validated computational predictions of the performance of SC, body centered cubic (BCC) and face centered cubic (FCC) arrangements of spheres, confirming that FCC is indeed superior (hmin = 1.12) to SC (hmin = 1.62). We conclude that the capability offered by additive manufacturing in controlling not only packing configuration but also shape, position and orientation of the geometric elements within the porous bed may, in the future, play a fundamental role in the design of highly efficient 3D-printed columns.