Pore size distribution of micelle-templated silicas studied by thermoporosimetry using water and n-heptane

Abstract

Thermoporosimetry, i.e., DSC measurements of melting point depression of water and heptane confined in mesopores, has been used for determination the pore size distribution of several mesoporous silicas synthesized with the use of micelle templates. Porosity of these materials was additionally characterized by low-temperature nitrogen adsorption and quasi-equilibrated thermodesorption of nonane. The pore size distributions obtained using the water thermoporosimetry were similar to those determined using the other methods, but the pore size values found for the narrow pore materials were underestimated by ca 1 nm. Too large pore sizes obtained for the wide pore silica from heptane thermoporosimetry were attributed to nonlinear dependence of the melting point depression on the reciprocal of the pore size.

Application of differential scanning calorimetry to study porous structure of hydrothermally modified silicas

“…This type of interactions is studied, among others, by differential scanning calorimetry (DSC) providing essential information about porous structure of the studied materials [10][11][12][13][14][15][16][17][18][19][20][21]. The method consists in studying phase solid/liquid transitions of the media contained in pores [15].…”

Porosity characterization of SBA-15 silicas with thermoporosimetry of water and n-alkanes – The effect of the probe liquid nature

“…The density taken into the calculations is the density of the adsorbate at the start of the measurement, i.e., solid density for a heating experiment. The detailed procedure was described earlier [15,28].…”

“…In our previous paper DSC measurements of the melting point depression profiles of water and n-heptane were applied for porosity characterization of four micelle-templated mesoporous silicas: SBA-15, MCM-41, MCM-41/TMB, and HMS [28]. The aim of this work was a complementary study on porosity of a series of ordered mesoporous SBA-15 silicas differing by the hexagonal unit cell parameter a, with particular focus on the role of the probe liquid type used in TPM experiments.…”

Application of quasi-equilibrated thermodesorption of hexane and cyclohexane for characterization of porosity of zeolites and ordered mesoporous silicas

“…The detailed synthesis procedures and porosity characteristics were published earlier (Majda et al 2012).…”