Rice Straw: A Major Renewable Lignocellulosic Biomass for Value-Added Carbonaceous Materials
: Carbonaceous materials are proven to be vital in day-to-day life as well as in advanced science and technology applications. Rice straw, a secondary agricultural lignocellulosic biomass, has drawn great attention for the production of value-added carbonaceous material. Because, it can provide an alternative economic, greener and sustainable resource of carbon to non-renewable fossil fuelbased precursors while controlling the worsening situation of environmental pollution due to improper disposal and stubble burning. In this review, recent developments in the production of carbonaceous materials from rice straw are presented. Biochar and activated carbon were reported to be the prime carbonaceous materials prepared from the rice straw. Thus, pyrogenic preparation of biochar and the influence of its pyrolysis temperature to the yield, composition, surface area, porosity and morphology are preliminarily discussed. This is followed by a detailed discussion on the preparation of activated carbon with an emphasis on the influencing reaction factors for improving the characteristic properties of the activated carbons. Additionally, the major characterization techniques dealing with determining the surface area and porosity (BET analyzer) and microstructure (secondary electron microscope (SEM) and transmission electron microscope (TEM)) for both the carbonaceous materials are also discussed. Finally, major applications of both the carbonaceous materials are briefly reviewed. Thus, the present review clearly highlights the usefulness of agricultural lignocellulosic waste rice straw for the conversion of waste to value-added carbonaceous materials.