Abstract: In the 0. 10 mol/Lacetate buffer solution with pH 4.4, a sensitive reduction wave of antimony-gallic acid complex has been obtained at-0. 47 V (vs. Ag/AgCl) using differential pulse voltammetry. The peak current is linearly proportional to the concentration of antimony in the range of 4. 0×10^-10to 8. 0×10^-8mol/Lafter a 2 min accumulation. The reaction mechanism has been discussed. It is shown that the current is caused by the reductioin of antimony (It) bonded in the complex which is adsorbed on the hanging mercury drop electrode, and that the adsorption of the complex obeys Frumkin isotherm. The proposed method has been applied to the determination of trace antimony in copper alloys with satisfactory results.

Key words: Antimony, Gallic acid, Differential pulse adsorptive stripping voltammetry