Synthesis and characterization of homogeneously mesoporous magnesium silicates with prospects of application in catalysis and adsorption

Abstract

Isotherms of low-temperature nitrogen adsorption–desorption by a mesostructured magnesium silicate material produced using a supramolecular cetylpyridinium template, liquid glass, and solutions of magnesium salts with different Mg/Si ratios have been measured. Homogeneously mesoporous adsorbents with a developed specific surface area (1045–1195 m²/g, from BET data) and high cumulative mesopore volume (1.210–1.646 cm³/g) have been synthesized. The samples' most specific characteristic features include a narrow mesopore size distribution with predominant sizes in the range ≈3.1–3.6 and a hysteresis of a hybrid shape indicating to the presence of a combination of tubular and slitlike mesopores in the form of TWT-structures. “Mesoporous molecular sieves” of the MCM-41 type and, alternatively, with the increase of the Mg/Si ratio, of the MCM-48 type with hexagonal and cubic pore structures, respectively, have been identified in the samples.