Abstract:

The effect and activation mechanism of thermal activated temperature on activity of red mud were analyzed.Phase transition temperature of red mud was analyzed by TG-DTA,and the changes of mineral composition and bond energy were also analyzed by XRD and FT-IR.Activity index was to assess the reactive activity of red mud.The test results showed that the diffraction peaks of dicalcium silicate was intensified after thermal activation.Calcite was decomposed into unstable and highly active substances. The stability of Si—O and Al—O bond were reduced.The activity index of activated red mud increased with the rising of activation temperature when it was no more than 700 ℃.Comparing with original red mud,the activity index of red mud activated at 700 ℃ increased 19.1%.While,the activity index of activated red mud decreased sharply when the thermal activation temperature was over 800 ℃.

Key words: red mud, thermal activation, activity index