A STUDY ON PHYSICO–CHEMICAL CHARACTERIZATIONS OF RED MUD DERIVED FROM ALUMINA PROCESSING PLANT IN TANRAI, LAMDONG PROVINCE

Abstract

In the present paper, physico-chemical characterizations including chemical composition, crystal phase composition, particle size distribution, particle morphology, physico-chemical processes during the sintering, functional groups on the surface of Tanrai red mud (Lamdong, Vietnam) were investigated. Tanrai red mud was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), lazer diffraction, thermogravimetry and differential scanning calorimetry (TG-DSC), scanning electron microscope (SEM), transmission electron microscope (TEM) and Fourier-transform infrared spectroscopy (FT-IR) analyses. The results showed that main crystal phases of red mud were hematite (Fe₂O₃), goethite (FeO(OH)) and gibbsite (Al(OH)₃). The amounts of Fe₂O₃ (46,7%), Al₂O₃ (19,1%), Na₂O (4,4%), TiO₂ (5,9%) in red mud were rather high that were suitable for manufacturing iron and steel, unsintered bricks, sintered bricks, and recovering TiO₂. High alkaline amount (pH > 11) of red mud with small particle size is a factor strongly concerning water and air polutions.