Synthesis and characterization of nano-silica from rice husk ash using an alkaline method extraction process

CARLOS ANDRES LOPEZ VARGAS; LAURA CORNAGLIA; BETINA FAROLDI

Santa Fe

Workshop; Workshop Franco-Argentino sobre Catálisis Heterogénea; 2023

El Instituto de Investigaciones en Catálisis y Petroquímica ?Ing. José Miguel Parera?, INCAPE (CONICET-UNL)

The synthesis of materials with attractive properties in catalysis can be carried out from agricultural biomass residues. In particular, SiO2 with high purity can be synthesized from rice husk combustion residues (ash). This is one of the most abundant residues from which a renewable and low-cost biosilica precursor can be obtained. This work presents results obtained from the recovery of silica with extraction percentages higher than 90% from rice husk ash using an alkaline method with sodium hydroxide followed by sol-gel precipitation with HCl and xerogel heat treatment. In this study, the effects of different extraction process variables on silica yields were evaluated and a design of experiments was used to establish the best extraction conditions. Likewise, all the synthesis materials as well as the ashes were characterized by XRD and FTIR and the TGA technique was used to study the recovery percentages of each experiment.