Rice husks include 20 wt% silicic acid, but it is discarded as domestic waste at a surplus biomass of over 200,000 tons per year. The purposes of this study is to use rice husks as a substitute for silica sand and subsequently to make soda-lime glass. For this, we evaluated the effects of utilizing silicic acid from rice husks and optimized their processing to make them suitable raw materials for glass. We succeeded in making soda-lime glass using silicic acid obtained from rice husks and also evaluated its physical characteristics. We made clear soda-lime glass with an amorphous structure by using rice husks after sufficiently reducing their carbon content. However, we found that the glass made from rice husks developed a green color because of Fe from rice husks.
