Statistical approaching of sol-gel process in preparation of silica aerogel derived from geothermal silica by several acids Free

Geothermal silica denotes as a potential source of silica for several purposes. One of them stands for silica aerogel. Preparing silica aerogel from leached geothermal silica must be brought into sol gel process. This paper observes the effect of acids concentration, kind of acids solution, and temperature in gelation process by statistical method. Responses were recorded as density, yield quantity, and acid volume. All data was processed by using Design Expert 8.0.6 to optimize operation condition. The result shows that optimum condition can be achieved by using sulfuric acid at 1.8 N and temperature of 56 °C. With these conditions, the gelation product of sodium silicate acquired density of 1.1 g/mL and gel yield of 76.3 g for each of 20 mL of sodium silicate used in gelation.