Rice waste feedstocks: A review of alternatives for their conversion into high-value added products

The increase in global population, expected daunting energy demands, and scarcity of resources has driven the search for new sustainable sources of materials, energy, and chemicals. In this context, biomass valorization has emerged as a promising technology to obtain high-value products in recent years. This research focuses on the valorization of rice production waste including straw, husk, and bran, due to their abundance, underutilization, and potential in generating a wide range of valuable products such as biofuels and materials. A systematic review was conducted regarding the valorization of rice production waste. The characteristics of biomass obtained from post-harvest rice production were explored, as well as the primary products derived from each of the discussed biomass feedstocks. Furthermore, the economic viability of the obtained products in their respective fields of application was evaluated, providing a solid foundation for future research and industrial applications. Different rice waste materials studied hold significant potential to obtain high‑value products including silica, adsorbent materials, biofuels, and various bioactive compounds.