Extraction of Silica from Different Solid Wastes and Its Application as Catalyst Support for Vapour Phase Oxidation of Aromatic Hydrocarbon

Abstract

In present study, the research work has been divided into two sections viz. Firstly, amorphous silica was extracted from different silica rich agricultural and industrial waste materials (fly ash, perlite and rice husk ash) via sol-gel method. The extracted silica (RHA-Si, Perlite-Si, FA-Si) was characterized using BET surface area, FESEM, EDS, XRD, NMR and FTIR techniques. The surface area and particle size of extracted silica was found to be 23.06-255.5 m2/g and 61-267 nm. Secondly, fly ash silica was used as catalyst support and modified desirably by loading different molybdenum weight percentages via acid impregnation method. The presence of MoO3 on the surface of extracted silica were confirmed by different characterization techniques. The kinetic studies of the FASi/Mo-15 catalyst for the vapour phase oxidation of benzene was also investigated by employing the Mars Van Krevelen model to analyze the reaction mechanism and rate of the process. The vapour phase oxidation reaction follows zero order kinetics, with faster benzene conversion occurring at lower intake concentrations and higher reaction temperatures.