학술논문
Equilibrium Studies of the Interaction of Vanadyl Ions with Catechol
Document Type
Article
Author
Source
Bulletin of the Chemical Society of Japan; May 1967, Vol. 40 Issue: 5 p1148-1152, 5p
Subject
Language
ISSN
00092673; 13480634
Abstract
A quantitative study of the interaction of vanadyl ions with catechol (H2A) has been carried out by means of potentiometric titrations of vanadyl sulphate with potassium hydroxide in the presence of varying concentrations of catechol. The formation of 1 : 1 and 1 : 2 complexes has been indicated. The equilibrium constants for the VO2++H2A\ightleftarrowsVOA+2H+and VOA+H2A\ightleftarrowsVOA22−+2H+reactions have been found to be 1.41×10−6and 7.76×10−9respectively, giving the values of 1.90×1015and 1.05×1013for the formation constants of 1 : 1 and 1 : 2 chelates respectively. Above pH 4, the 1 : 1 complex has been shown to hydrolyze, and the equilibrium constant for the VOA+H2O\ightleftarrowsVO(OH)A−+H+reaction has been found to be 7.94×10−6.