Chinese researchers have turned waste into treasure and successfully extracted nano-silica, an indispensable material for manufacturing rubber and plastics, from rice husks. According to Professor Wang Zichen from the College of Chemistry, Jilin University, the inventor of this technology, rice husks contain a large amount of silicon. Therefore, even if buried, they are difficult to degrade in the soil and easily cause changes in soil composition. Silicon dioxide is an essential additive in plastics and rubbers, which can improve the strength and transparency of plastic and rubber products. In the past, silicon dioxide was mostly extracted from ores, but ores have complex components, requiring multiple processes to remove impurities before extracting the required components. In addition, the ore waste residue after extraction cannot be properly recycled and becomes a threat to the environment. After years of research, Professor Wang Zichen has successfully utilized the high silicon content in rice husks. By removing inorganic substances, fibers and impurities, and burning off carbon components, silicon dioxide was extracted from rice husks, accounting for about one-fifth of the rice husks. No waste is generated during this process, and all rice husks are fully utilized. Moreover, in the process of carbon removal, carbon can also be retained through specific procedures and used as raw material for activated carbon. It is known that silicon dioxide processed from ores is mostly micron-sized, while that processed from rice husks is nano-sized, whose molecular volume is one percent of micron-sized particles. Therefore, its strength and transparency are better than micron-sized silicon dioxide, but the cost is much lower. At present, this technology is ready for large-scale industrial application.
Back to News Page