STUDY OF THE ENHANCEMENT OF THE BORON-BERYLLON-III SYSTEM BY ANION SURFACTANT USING OSCILLOPOLAROGRAPHY

A sensitive oscillopolarographic method for the determination of trace boron, based on the complex adsorptive current of the boron-beryllon III system with the anion surfactant sodium dodecyl sulfate (SDS), whi ch increased the current response about 16 times compared to that obta ined without SDS, was reported. Under optimum experimental conditions the limit of detection was 0.5 ng/ml boron. The coordination ratio and the conditional stability constant (K) of the boron-beryllon III comp lex were estimated to be 1:1 and 3.8 X 10(5), respectively. The existi ng form of beryllon III and boron-beryllon III at pH 3.7 has been conf irmed. The electrochemical behaviour of beryllon III and its complex w ith boron(III), both in the absence and in the presence of SDS in acet ic acid-ammonium acetate (pH 3.7) was investigated. On the surface of a dropping mercury electrode, the adsorption of the B(III)-beryllon II I complex in the presence of SDS obeyed the Frumkin adsorption isother m. The adsorption coefficient (<(beta)over bar> = 6.4 X 10(4)), the at traction factor (<(nu)over bar> = 1.41) and the amount of saturated ad sorption (Gamma(s) = 5.8 X 10(-10) mol/cm(2)) were evaluated. The mech anism of the electrode reaction and the enhancement mechanism of SDS h ave been suggested.