Influence des composés organiques sur la vitesse d'apparition du complexe de transfert de charge 1Sn(II)—4Sn(IV) dans les bains acides d'étamage brillant

Abstract

The effect of a number of organic compounds on the rate of formation of 1Sn(II)–4Sn(IV) charge transfer complex in acidic stannous sulphate solutions and on the stability of these solutions has been determined by measuring, spectrophotometrically, the change of absorption of these solutions with time. From the results, it is possible to classify these organic compounds into three broad categories in terms of how they affect the formation of the charge transfer complex and the stability of the solution.These results have been interpreted taking into account that the formation of the 1Sn(II)–4Sn(IV) complex depends on the initial concentration of stannic ions present as an impurity in the stannous sulphate solution, the rate of oxidation of the stannous ions, the rate of hydrolysis of the stannic ions, and the stability of stannic colloids that are formed.