Production of amorphous silica and activated carbon from rice husk char obtained from two stage gasification process

Abstract

In this study the rice husk has been subjected to two-stage gasification to obtain syngas, tar and char. The rice husk char is subjected to alkaline extraction to obtain amorphous silica and activated carbon. The products have been characterized by methods such as BET, FTIR and XRF. The silica obtained from acid leached rice husk has BET specific surface area of 311.68 m²/g and purity of 88.85%. The BET specific surface area of activated char increase from 102.49 m²/g to 567.03 m²/g after the activation process. The silica extraction using carbon dioxide (CO₂) precipitation is found to be more profitable than acid precipitation.