As an agro-waste material the rice husk is abundantly available is rice growing areas. In many areas rice husk
after burning involves disposal problems because of higher quantities of silica present in it. Rice husk contains
about 20 per cent silica, which is present in hydrated amorphous form. On thermal treatment the silica converts
into crystobalite, which is a crystalline form of silica. However amorphous silica can be produced under controlled
conditions ensuring high reactivity and large surface area. Leaching the rice husk with organic acids and alkalies
removes the metallic impurities from its surface. How a dilute solution of potassium permanganate affects the rice
husk is the subject of this research paper. The rice husk was treated with the dilute solution of potassium
permanganate at room temperature and then analyzed by SEM, TGA and the ash by analytical treatment after
burning under controlled temperature. The SEM results revealed that the protuberances of the rice husk were
eaten away by the solution of potassium permanganate. Pyrolysis of rice husks showed that the thermal
degradation of the treated rice husk was faster than the untreated rice husk where as analytical results confirmed
the presence of more amorphous silica than untreated rice husk.
