Preparation of silica gel from rice husk ash using microwave heating
Keywords:Rice husk ash, Silica gel, Waste utilization, Microwave, Dielectric heating, Sodium silicate
AbstractThe purpose of this research is to separate silica gel from rice husk ash by microwave heating. The experiments were performed by heating rice husk ash in sodium hydroxide solution with various concentrations in microwave oven for 5 or 10 minutes. The obtained sodium silicate was neutralized to give silica gel. The best condition for silica gel production was the reaction with 2.0 M sodium hydroxide at microwave power of 800 W for 10 minutes. The ability of silica gel as desiccant was investigated by adsorption test. The results showed that silica gel prepared by low concentration of sodium hydroxide solution had the highest ability of water adsorption. The power of microwave and volume of reactions seemed to have only little effect.
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