Seawater Neutralized Red Mud as an Adsorbent

‘Red mud’ or ‘bauxite residue’, a waste generated from alumina refinery is highly alkaline in nature with a pH of 10.5 12.5. Enormous quantity of red mud is generated worldwide every year posing a very serious and alarming environmental problem such as alkali seepage in ground water and alkaline dust generation. Seawater neutralization is one of the methods for treating it and making it non-hazardous. Reuse of seawater neutralized red mud after heat activating it for fluoride adsorption is studied in present paper. Increase in activation temperature of seawater neutralized red mud resulted in increase in adsorption of fluoride. Moreover low adsorption may be increased by acid treatment of heat activated seawater neutralized red mud.