Pore analysis

In general, catalyst consists of pore in the range of, micropore, mesopore or macropore depending on the preparation conditions and compositions. To determine the pore size distribution within the catalyst, pore analysis is essential. Knowing the pore size distribution gives an idea about accessibility of the reactants to the active sites. The pore analysis consist of determining the average pore size, average pore volume and pore size or pore volume distribution.

Total pore volume and average pore size

Total pore volume is defined as the liquid nitrogen volume at a certain P/Po (=0.95).Total gas adsorbed at certain P/Po (=0.95) is converted to liquid volume assuming pores are filled with liquid adsorbate

Average pore size can be estimated from the pore volume. Assuming cylindrical pore geometry average pore radius (r) can be expressed as: