POSITRON POROSIMETRY STUDY OF MECHANICAL STABILITY OF ORDERED MESOPOROUS MATERIALS

摘要

In the last years a family of ordered mesoporous materials called M41S~1 was intensively developed. It resulted in invention of variety of M41 S class materials differing in shape, size and ordering of the pores. Remarkable properties of these molecular sieves, such as high specific surface area (over 1000 m~2/g), high pore volume (about 1 m~3/g) and a narrow distribution of pore sizes, make it attractive for various industrial applications. In order to successfully use M41 S molecular sieves as supports, adsorbents, catalysts etc. their mechanical stability have to be known. So far structural stability was investigated mostly by adsorption/desorption techniques (nitrogen or organics), mercury porosimetry and X-ray diffraction (XRD)~(2,3,4). These methods have some limitations that may distort obtained results in the case of studies of structural stability.