Colloidal processing and CO2 capture performance of sacrificially templated zeolite monoliths

Sacrificial templating of suspension cast and subsequently thermally treated zeolite monoliths with glassy carbon spheres and fibers yielded zeolite 13X and silicalite-1 monoliths with macroporosities up to 50 vol%. Homogeneous distribution of the macroporosity in hierarchically porous monoliths was obtained by tailoring the surface chemistry of the carbon particles by polyelectrolyte-assisted adsorption of zeolite particles. The effect of amount of kaolin binder and temperature for the thermal treatment on the monoliths strength, surface area and CO2 uptake was studied by diametral compression tests, electron microscopy, X-ray diffraction and gas adsorption. Cyclic adsorption and regeneration measurements showed that zeolite 13X monoliths display a high CO2 uptake while the silicalite-1 monoliths could be regenerated with a relatively low energy penalty.

► We demonstrate structuring of hierarchically porous zeolite monoliths.
► Structured zeolite monoliths show high CO2 adsorption capacity.
► Addition of 5 wt% of kaolin to zeolite monoliths ensures a mechanical stability.
► Cyclic adsorption and regeneration show that structured monoliths are robust.