General and Inorganic Chemistry:Physicochemical features of the formation of siliceous porous mesophases Effect of duration and temperature of the hydrotherma treatment on the structural and textural properties

摘要

The results of investigation of mesoporous mesophase materials C12-SiO_2-MMM and C16-SiO_2-MMM prepared at the optimized composition of the reaction mixture and different durations of hydrothermal treatment (HTT) at 120 deg C and 140 deg C are presented. Hydrothermal treatment at 120 deg C influences slightly the specific surface area and the olume of the mesopores but gives a more ordered structure. Prolonged HTT at 140 deg C results in irreversible structure degradation. The samples obtained with the optimal HTT duration are characterized by the minimum width of X-ray reflections, the maximum surface and volume of mesopores, and the minimum external surface.