Synthesis and Properties of Gyrolite

The second chapter of the monograph starts with the comprehensive literature review on the natural gyroliteNatural gyrolite (properties, formation, and crystal structureCrystal structure) and the background information about hydrothermal synthesisHydrothermal synthesis of gyrolite. In this chapter, the dependence of the main properties (specific surface areaSpecific surface area, predominant pore size and their radial distribution, crystal size, and shape) of synthetic gyrolite on the duration of hydrothermal synthesisHydrothermal synthesis is described. It was found that gyrolite is stable till 168 h during hydrothermal treatment at 200 °C temperature in mixtures of calcium oxide and amorphous silicon dioxide. Furthermore, it was shown that, by prolonging the duration of hydrothermal synthesisHydrothermal synthesis from 32 to 168 h, the crystallite sizeCrystallite size of synthetic gyroliteSynthetic gyrolite increases from 44 to 95 nm, while the amount of the adsorbed and interlayer waterInterlayer water in the structure of synthetic gyroliteSynthetic gyrolite as well as the specific surface areaSpecific surface area and total pore volumeTotal pore volume decrease.