Rethinking reactor design: additive manufacturing applications in chemical engineering

Industrial heterogeneous packed bed reactors are commonly used in the chemical process industries to produce things like plastics, refine fuels, synthesize fertilizers and so forth. They consist of a pressure retaining wall (a pipe or pressure vessel) which is filled with discrete pellets coated with a catalytically active material to help speed the reaction of interest. In this way the entering fluid reactants will react much faster at milder pressures and temperatures which reduces the size of the reactor and enables commodity chemicals to be made at an astonishing scale.

Industrial packed-bed reactors are often limited by poor heat transfer, non-uniform flow distribution, high pressure drop, and low mechanical durability of the pelletized catalysts. Additive manufacturing (AM) of monolithic catalysts offers a potential solution to these issues, particularly for highly exothermic and endothermic reactions. In this presentation, new concepts in reactor design enabled by AM will be explored:

• Simultaneous AM of the pressure retaining the barrier and monolithic catalyst support.
• AM of triply periodic minimal surface structures and the potential benefits of a sheet gyroid reactor configuration.
• Multi-scale control between the catalyst support geometry and its microstructural properties.
• Incorporation of the active metal precursor in AM process to eliminate the catalyst infiltration step.
• Use of topology optimisation in monolithic catalyst support design.
• Example application in high-test hydrogen peroxide decomposition.
• Prospects for important industrial reactions like steam-methane reforming, ammonia synthesis, Fischer-Tropsch synthesis, and methanol synthesis.