Rice husks (RHs) have recently attracted high attention due to their potential for many applications, including construction materials, composite materials, adsorption materials, chemical production, and power generation. RHs are an appealing alternative because of their low cost and high silica content. So far, most researchers mainly focus on the utilization of one component (such as silica) while ignoring others. Comprehensive utilization of RH biomass and diversified products are the key goals for this research field. In this thesis, the two main components of RHs, silica and lignocellulose, were extracted from RH biomass. The high tempered calcination served as the extraction process of the highly reactive RH silica nanoparticles. Because of its remarkable physiochemical properties, green phosphor of Zn2SiO4:Mn2+ was synthesized under a high temperature pyrolysis method. This study also investigated the effects of reaction temperature and Mn2+ doping concentration on the photoluminescence properties of the RH silica phosphor. By comparing with the phosphor prepared from commercially used silica, RH silica phosphor showed superior photoluminescence properties. Because RHs are an inexpensive resource and the RH silica phosphor exhibited better performance, it should be considered a promising alternative. The second part of the thesis studied the extraction of the lignocellulose from RH biomass by using ionic liquid (BMIMCl). Through liquid nitrogen frozen and thaw (NFT) process, water regeneration, and CO2 supercritical drying, the light and porous lignocellulose aerogel was prepared. In addition, the lignocellulose aerogel can be further converted to a carbon aerogel via a facile pyrolysis process. Because of the inherited porous structure, the carbon aerogel is expected to find wide applications in many areas. Silane agent (MTMS) modification of the lignocellulose aerogel is another route to expand its applications. The treated lignocellulose aerogel exhibited to be highly hydrophobic, making it effective in oil spill adsorption. Based on the comprehensive utilization strategy, the RH residue separated from IL solution was used to prepare highly active and amorphous silica nanoparticles, which also have widespread application.
