Synthesis of mesoporous silica materials from incineration bottom ash for the removal of toluene

Abstract

In Taiwan, most of the municipal solid waste is incinerated, and more than 930 thousand tons of bottom ash is produced in 2014. Incineration bottom ash contains major element of silicon that could be as a silicon source for the synthesis of mesoporous materials. Our previous study investigated the conditions for alkaline fusion to extract silica from incinerator bottom ash and verified that the high specific surface area of mesoporous silica could been synthesized from bottom ash. To expand the application of mesoporous silica materials synthesized from bottom ash, the effects of operation conditions of adsorbent weight (0.2, 0.5, 0.8, 1.5 g), adsorption temperature (25, 30, 35°C) and toluene concentrations (900, 1100, 1300, 1500 ppm) on toluene removal were determined in this study. Moreover, the gas flow and the oxygen content were 500 sccm and 10%, respectively. The mesoporous materials synthesized from bottom ash possessed the best adsorption capacity of toluene (ca. 124 mg g-1) at the toluene concentration of 1100 ppm and at the reaction temperature of 25°C. The results showed that the mesoporous silica prepared with incinerator bottom ash have potential to be used as an adsorbent for the removal of toluene.