Synthesis of SiO2 nanoparticle from bamboo leaf and its incorporation in PDMS membrane to enhance its separation properties

A low-cost indigenous silica powder at nanoscale was synthesized by thermal combustion and alkaline extraction technique from bamboo leaf ash. The bamboo leaf ash was prepared by heating the bamboo leaf at 750 degrees C for 5 h. The amorphous SiO2 nanoparticle with an average particle size of 20 nm was used for the industrial application. The synthesized nanoparticle as a filler was mixed with polydimethylsiloxane (PDMS) polymer solution to synthesize a nanocomposite membrane by a solution casting method. The morphological study was done using high-resolution scanning electron microscopy (HRSEM) with an energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and the chemical structure was studied using Fourier-transform infrared spectrometry (FTIR). Thermogravimetric analysis (TGA) analyzed the thermal stability of the membranes, and the hydrophobicity was measured using contact angle analyzer. Separation of the acetic-water mixture was carried out by nano-composite PDMS membrane to study the effect of silica loading on the PDMS membrane. It was observed that the presence of SiO2 nanoparticles significantly improves the pervaporation flux as well as the thermal stability.