Electrochemical study of some three-derivative compounds of 1-phenyl-4-butyldithiocarboxylate-5-hydroxypyrazol (3D-FBDTCHP)

An electrochemical study related to the electrooxidation of the 3-hydroxyl and 3-methyl derivatives of 1-phenyl-4-butyldithio-carboxylate-5-hydroxypyr azol in aqueous ethanolic solutions covering a wide pH interval has been pe rformed. In this study, these compounds are considered as potential collect or agents for copper mineral sulfide flotation. From the potentiodynamic pa rameters for both compounds in solution, as well as for the 3-methyl deriva tive adsorbed on a glassy carbon electrode surface, it was established that these compounds undergo a dimerization process involving the formation of the respective bisthiocarbonyl disulfide derivative. On the basis of the vo ltammetric and coulometric data, as well as from the analysis of the produc t obtained after a preparative electrolysis carried out with the 3-methyl d erivative, a mechanism accounting for the nature of the reaction product in aqueous ethanolic solutions is proposed. (C) 2000 Elsevier Science B.V. Al l rights reserved.