(616e) 3D Micro-Extrusion of Hierarchical Porous Structures for Sorption and Catalysis

This contribution presents the potential of 3D printed materials in the area of Carbon Capture and Utilisation (CCU). Carbon Capture, Utilisation and Storage (CCUS) technologies could enable large (90-95%) reductions in CO₂ emissions from power generation using fossil fuels and energy-intensive industrial processes. In CCU CO₂ is captured and the CO₂, as source of carbon, is utilized as a raw material for other processes like the manufacture of fuels, carbonates, polymers and chemicals. Capturing CO₂ using solid adsorbents is a promising alternative to state-of-art technologies using amine solutions as absorbents. In this study, solid adsorbents for CO₂ capture and heterogeneous catalysts for chemical conversion of CO₂ have been manufactured by 3D printing. 3D printing allows to tailor the porous architecture in view of optimal heat and mass transfer properties combined with a low pressure drop leading to an improved efficiency of sorption and catalytic processes.

3D printing was performed by a technology known as Direct Ink Writing or robocasting, which is based on the direct extrusion of viscous paste through a nozzle. By the controlled stacking of the extruded fibers layer by layer, structured porous architectures can be produced in a wide variety of materials that find application in sorption and catalysis ranging from metals supports, zeolites, oxide ceramics, activated carbon, (functionalised) polymers,... and their combinations. The paste formulation (active powder material, (in)organic binder, rheology modifier, dispersants,...), extrusion conditions and post-processing conditions have an impact on the porosity, structural properties, mechanical strength and performance (selectivity and kinetics) of the materials. Different strategies to control the porosity within the fibers by the use of different (in)organic binders have been developed.

Figure 1: 3D printed structures for CO₂ capture: (a) activated carbon, (b) zeolite.