VOLTAMMETRIC BEHAVIOUR OF BRILLIANT CRESYL BLUE
Liu Yanming (Department of Chemistry, Shanxi University)Wang Erkang (Changchun Institute of Applied Chemistry, Academia Sinica)
Voltammetric behaviour of brilliant cresyl blue(BCB)was studied by do polarography, differential pulse polarography, cyclic volammetry. Depending on pH, one to four waves(peaks) appear. First wave is of oxidation one, other three waves are reduction ones. First wave is of difussion-controlled, twoelectron one corresponding to formation of the complex of Hg(Ⅱ) -BCB, wave Ⅱ is an adsorption pre-wave. The sum of both wave Ⅱ and wave Ⅲ is of difussion-controlled, two-electron one corresponding to reduction of one form of BCB. Wave Ⅳ is of difussion-controlled. two-electron one corresponing to reduction of another form of BCB. From experimental results, the mechanism for the electroreduction of BCB has been discussed, and the apparent dissociation constant for BCB has been determined.