Collect. Czech. Chem. Commun. 1996, 61, 999-1009

The Mixed Adsorption Layers of Butanol/Thiourea and Butanol/Toluidine at the Interface Hg/Aqueous Perchlorate Solution

Jadwiga Saba

Faculty of Chemistry, M. Curie-Skłodowska University, 20031 Lublin, Poland


Properties of mixed, two-component adsorption layers of butanol/thiourea, butanol/m-toluidine and butanol/p-toluidine in 1 M NaClO4 were investigated. The systems were characterized by the measurements of differential capacity, zero charge potential and surface tension at this potential. The data were analyzed to obtain the surface pressure and relative surface excess of thiourea, m-toluidine or p-toluidine as a function of charge and bulk concentration of these substances. The standard Gibbs energy of adsorption and parameters α, B obtained from the Frumkin and virial isotherms were compared. The electrostatic parameters of the inner layer were determined.

Keywords: Mixed adsorption; Mercury; Differential capacity; Surface tension.