Table 2: Chemical composition of the three kinds of red mud (w/%).

Type of sampleAl2O3SiO2Fe2O3CaONa2OK2OMgOTiO2SO3

Bayer red mud from wetting process20.80 ± 0.1822.35 ± 0.107.73 ± 0.0618.51 ± 0.198.83 ± 0.072.41 ± 0.051.40 ± 0.024.98 ± 0.053.00 ± 0.02
Bayer red mud from drying process20.52 ± 0.0922.47 ± 0.167.69 ± 0.0918.42 ± 0.078.94 ± 0.042.50 ± 0.031.52 ± 0.074.92 ± 0.023.01 ± 0.03
Sintering red mud7.28 ± 0.0724.02 ± 0.188.50 ± 0.0544.00 ± 0.200.69 ± 0.050.25 ± 0.031.37 ± 0.054.17 ± 0.081.09 ± 0.02