Modification of Red Mud (Bauxite Residue) Into Sponge Base Catalyst Through Soda-Lime Calcination
Red mud is a residue from bauxite processing during the production of alumina. In this paper, modification of this waste was studied by examining soda-lime calcination at 600-1000˚C for 2 h. The presence of sodium carbonate and limestone as additives revealed significant influence on the morphology, crystallinity and basicity. The modified red mud had accumulated large number of agglomerates and formed a unique appearance called sponge structure. The spaces between agglomerates were 1-5 μm, so that favorable for transesterification reaction for biodiesel production. In addition, the crystallinity of modified red mud was getting better during calcination and the basicity tend to increase.
Keywordsó Red Mud, Sponge Morphology, Base Catalyst, Soda-Lime Calcinations.