Synthesis and characterization of silica aerogel from corn husk waste via ambient pressure drying

Corn husk waste possesses a relatively high silica content which can be utilized as the raw material to produce useful silica compounds. In this study, natural silica aerogel was synthesized from corn husk using a combination of sol-gel and cationic exchange methods under ambient pressure drying conditions with the help of MTCS as a surface modification agent. This study aims to determine the feasibility of the synthesis method and the physical properties of the as-synthesized silica aerogel. The purity and crystallinity of silica aerogels were analyzed using Fourier Transform Infrared (FTIR) and X-ray Diffraction (XRD), while its morphology was examined using Scanning Electron Microscope (SEM). The optimum synthesizes parameters of silica aerogel were observed at cation resin to sodium silicate filtrate ratio of 2:1, with the addition of 0.4 ml MTCS and drying under ambient pressure at 60°C for 4 hours, continued by 120°C for 2 hours. The as-synthesized silica aerogel possesses high purity, with an amorphous crystal structure and yield of 46.44 wt.%. Silica aerogel also has a porous morphology with pore diameters ranging from 1 to 3 μm.