Rice straw as a new resource for some beneficial uses

The objective of the present work is to make an environmental impact assessment study for the production of beneficial materials from rice straw. Rice straw has been liquefied, and a number of liquefaction variables have been investigated to determine the optimal liquefaction conditions. Results show that the reaction conditions, such as catalyst concentration, liquefaction temperature, time and material to liquor ratio are of great influence on the liquefaction process. Liquefaction of rice straw was carried out directly after grinding and also after pulping process. Preparation and evaluation of carboxymethyl cellulose from cellulosic materials obtained from rice straw was carried out. The work was extended to the extremely fine white grayish powder that was obtained on burning rice straw and/or the residues obtained after liquefaction process of rice straw at 550 °C. The remaining powder was characterized and evaluated; X-ray analysis showed that about 69% of this remainder was found as silica. The size of the particles ranged from 18 to 68 nm. The powder was tested for application as a filler or extender pigment in some paint formulations, promising results were obtained.