Synthesis and characterization of nano-porous silica aerogel by applying a novel supercritical drying system
Volume Title: 1
1Nanostructures and Biopolymers research Laboratory, Department of Chemical Engineering, Faculty of Engineering, University of kashan, Kashan, Iran
2Nanostructures and Biopolymers research Laboratory, Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan, Iran
In this study, a simple and novel supercritical dryer system was designed to drying of wet gel, aiming to the removal of the high energy-consumption equipment such as pump and strong compressor. The system is capable to provide the supercritical state in the fluid, only using the control of thermodynamic conditions. To ensure the proper efficiency of developed dryer system, the silica aerogel was successfully derived from tetraethyl orthosilicate as starting material of silica. The amorphous phase of silica was identified by XRD analysis. The specific surface area, and average pore size were measured about 659 m2/g and 22 nm, respectively, via BET method. N2 adsorption-desorption isotherm curve shown the type IV isotherm, indicating the mesoporous structure with cylindrical and capillary pores. The bulk density and porosity were measured about 0.11 g/cm3 and 95%, respectively. The FESEM micrograph indicates spherical morphology, porous structure and open mesopores in range of 10-30 nm. These results confirm the proper efficiency and performance of designed supercritical dryer system.