Rice Husks - Potential Source of Cellulose Microfibers/Nanofibers and Biogenic Silicon Dioxide Nanoparticles

Abstract

Rice husks are among the world's most significant agricultural waste. On the one hand, their use is related to solving an environmental problem; on the other hand, they use this material as a potential advanced material for many applications. Due to their chemical composition, rice husks can be a source of cellulose fibers and silica nanoparticles. The present text presents the essential characteristics of fibers and nanoparticles that were obtained from the treated shells at the same time. The fibers released from the rice husks have diameters ranging from 5 to 10 μm, the length being in the hundreds of micrometers. The surface of the fibers is not smooth, a sub-micrometer structure is visible, which indicates the potential possibility of further pulping into nanofiber formations. Silica nanoparticles are found on the surface of fibers released from rice husks and beyond. Nanoparticles form clusters of tens of nanometers; the sizes of individual particles are at the level of nanometer units. In the modified hulls, the accompanying technique did not identify the accompanying elements found in the original rice hulls.