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

Molecular sieves and zeolites are microporous materials widely used for their shape-selective (1), adsorptive and/or catalytic properties (2), which are closely related to their framework structure (cavities, cages, 1D-, 2D-, or 3D-channel-systems), Among the wide variety of synthetic crystalline microporous materials, those corresponding to the MFI topology (3) are of great industrial importance Their framework structure is composed of two types of intersecting channels both limited by 10-membered oxygen rings : the straight channels (slightly elliptical ≈ 5.7×5.3 Å) run parallel to the [010] direction (b-axis), whereas the zig-zag channels (nearly circular ≈ 5.5 Å) run parallel to the [100] direction (a-axis)