Investigation on SiO₂ derived from sugarcane bagasse ash and pumice stone as a catalyst support for silver metal in the 4-nitrophenol reduction reaction

The application of naturally abundant resources as alternative raw materials has been intensively studied because it is more economical and is also able to reduce solid waste generated by various industries. In this study, SiO₂ was successfully extracted from sugarcane bagasse ash and pumice stone by using a low-temperature alkaline extraction method and acid precipitation process with high purity levels (98.4% and 96.3%, respectively). The extracted SiO₂ was used as a catalyst support for Ag₂O, where the two components were integrated with the impregnation method. The resulting catalysts were characterized to understand their structural features, as well as to see the catalytic performance. All samples of catalysts succeeded to reduce 4-nitrophenol, with differences in their reaction rates. The sample of Ag₂O/SiO₂, in which SiO₂ was extracted from pumice stone, shows higher catalytic activity than that of sugarcane bagasse ash. From the analysis in this study, it is found that the aforementioned phenomenon is closely related to the structural properties of both Ag₂O and SiO₂ as the catalyst and its support.