日本ゼオライト学会　刊行物 Publication of Japan Zeolite Association

Previously, we found that a porous gel having a monolithic microhoneycomb structure with straight and aligned µm-sized channels can be synthesized by unidirectionally freezing a soft precursor hydrogel of the material. In this work, we applied this method to a silica hydrogel in which zeolite particles were uniformly dispersed, and found that this mixture could be casted into a monolith having a similar microhoneycomb structure. The monolith consists of walls formed by zeolite particles bound by silica, the thickness of which is similar to the size of the particles. Therefore, such monoliths can be regarded to have a unique hierarchical pore system in which micropores of the zeolite are directly connected to µm-sized macropores. We also verified that the pressure drop which occurs when fluids are passed through such monoliths is extremely small. Therefore this method allows the synthesis of a monolith in which short diffusion paths and low resistance to fluid flows are compatible, a feature which cannot be achieved in materials synthesized in the form of particles.