Structural, Morphological and Physiochemical Analysis of SiC8H20O4/C2H5O/C7H16 Modified Mesoporous Silica Aerogels

Silica Aerogels are widely recognized and have grown a considerable interest among researchers due to their unique properties. Using Rice Husk Ash as the main precursor and Ambient Pressure Drying, the present study synthesized and compared 4 different mesoporous silica aerogel variants by independently modifying them with TEOS (SiC8H20O4), Ethanol (C2H5O) and n-Heptane (C7H16). The variants were characterized through BET, SEM, EDX and XRD respectively. As per results, the highest porosity %, surface area, pore volume, average pore size and lowest volume shrinkage of 85%, 312 m2/g, 0.76 cm3/g, 9.6 nm and 91.16% were observed in sample treated separately with TEOS, ethanol and n-heptane (SGTEH-Iso). However, the sample treated with simultaneous solvent exchange/n-heptane aging (SGTEH-Sim) followed next with 79.5%, 298 m2/g, 0.75 cm3/g, 9.2 nm and 91.86% respectively. Moreover, TEOS, ethanol and n-heptane were shown to enhance silica purity, strengthen gel network and suppress crack formation during ambient pressure drying. Finally, due to their high porosity, pore volume and average pore size, variants SGTEH-Iso and SGTEH-Sim can have potential application as adsorbents for heavy metal removal from wastewater.