SURFACTANTS IN SPECTROPHOTOMETRIC METAL DETERMINATION WITH 5-BR-PADAP - SENSITIVE SPECTROPHOTOMETRIC DETERMINATION OF SILVER WITH DODECYL-SULFATE (SDS)

The conditions for the formation of ternary complexes of selected metal ions: V(V), Ni, Cu(I), Cu(II), Pd, Ag, Cd, Hg(I), Hg(II), Tl(I), and Tl(III) with 5-Br-PADAP and surfactants: sodium dodecylsulphate, Triton X-100 or zephiramine have been examined. The sensitive (epsilon = 6.0 X 10(4) l mol-1 cm-1 at lambda = 540 nm) and precise method for the determination of microgram amount of silver, based on ternary Ag-(5-Br-PADAP)-SDS system has been developed (with preliminary separation of silver by electrolysis and sequestration of interfering metals by EDTA). By means of the developed procedure the silver content was determined in hydrated copper sulphate p.a. (POCH) (5.8 x 10(-5) %) and in copper alloy (9.7 x 10(-3) %).