Abstract: Muscovite has strong negative charge due to the ion substitution，which lead to their interlayer ions have strong electrostatic attraction，and small cation exchange capacity (CEC).As a result，it is difficult for the exfoliation of muscovite and the preparation into two dimensional nanomaterial.Effect of various treating methods on the CEC of muscovite was studied.The experiment results showed that CEC increase of 0.11 mmol/g was obtained on muscovite after calcination at 750 ℃ due to the dehydroxylation.However the value of CEC only had a little increase when muscovite was treated with NaB(C₆H₅)4 after calcination at 750 ℃.A dramatical increase of CEC to 0.65 mmol/g was found when treated with LiNO₃ after calcination at 750 ℃.The XRD and IR analysis of muscovite showed that the increase of the basic spacing and weakening of the attraction force from layers to interlayer ions could be achieved when calcination and LiNO₃ treatment applied.Calcination and LiNO₃ treatment are an important methods for the preparation of high value-added muscovite.

Key words: Muscovite, Calcination, Ion exchange, Cation exchange capacity