Abstract:
In the agricultural countries, rice husk is an abundant waste, especially as one of the largest
sources of silica (SiO2) production that can be produced. By complete combustion, to about 87% -
97% SiO2 content can be produced from rice husks. Alkaline solution is used as a solvent in the
solid-liquid extraction production of rice husk ash SiO2. The mass of 10 grams of rice husk ash was
weighed for the extraction process added with 80 ml of potassium hydroxide (KOH) solution with
10%, 15% and 20% various concentration to extract the SiO2 content. In a systematic study, for 60
minutes the rice husks were soaked and washed using HCl and then heated in a muffle furnace. The
results of this study showed that all samples are succeeded in homogenizing SiO2 with purity close to
90%. Furthermore, through Energy-Dispersive X-ray Spectroscopy (EDS) analysis was proven these
results obtained through solid-liquid extraction of KOH from rice husks. Natural SiO2, known as
biosilica, is useful and has potential in reinforcing compounds, including applications as filler in tires
and natural rubber compounds.
