Calorimetric and Potentiometry Investigations of the Acceptor Compounds Intercalations into Graphite

Abstract

In the work the intercalation of H₂SO₄ (from 98% to 76%) into graphite (oxidizer—(NH₄)₂S₂O₈) was investigated by potentiometry. It was established that the redox potential of oxidizer solution depends on the concentration of H₂SO₄. The criterion for the formation of graphite hydrogenosulfate¹ (GHS) was corroborated by the experiment. It was shown that stage of GHS is determined by the redox potential of the oxidizer solution. The system C-K₂Cr₂O_7–94% H₂SO₄ was investigated by calorimeter and potentiometer methods in situ. The “overoxidation” of stage 1 GHS was observed during the calorimetric investigation (the second exo—effect) but not seen on the potentiometry curve. It was proposed that more high oxidation of graphite and the formation of ion—covalent bonds take place during “overoxidation”.