Fig. 5 shows the results of thermo gravimetric analysis of poroussilica from bagasse ash prepared without PEG templating, silica-PEG hybrid and PEG-free silica after PEG removal. For all samples,a weight loss is detected from room temperature to approxi-mately 150◦C, indicating the loss of physically adsorbed water.In the temperature range from 150◦C to approximately 470◦C,the weight of silica prepared without PEG and PEG-free silica isrelatively constant, and then decreases slowly. In contrast, theweight of PEG-silica hybrid remains relatively constant from 150◦Cto approximately 200◦C and then decreases sharply by a furtherincrease in the temperature. The weight loss may come from thedecomposition of PEG. Thus, it was confirmed that PEG has beensuccessfully removed from PEG-silica hybrid and the porous silicadiscussed in the following are relatively free from PEG.