Solid-phase extraction of copper with lead 4-benzylpiperidinedithiocarbamate on microcrystalline naphthalene and its spectrophotometric determination

Abstract

Using lead 4-benzylpiperidinedithiocarbamate complex (Pb(4-BPDC)(2)), a solid-phase extraction method was developed for pre-concentration and spectrophotometric determination of copper in water samples. In this method, copper in large volume liquid phase quantitatively replaces lead on colorless Pb(4-BPDC)(2) complex and naphthalene solid phase mixture forming Cu-4-benzylpiperidinedithiocarbamate complex (Cu(4-BPDC)(2)). The solid phase containing colored Cu(4-BPDC)(2) is dissolved in chloroform and its absorbance is measured at 437 nm against the reagent blank. The range of linearity is 0.4-10 mugml(-1) of copper in chloroform, the molar absorptivity of the complex determined from the linear portion of Beer's law plot is 8.197x10(3) lmol(-1)cm(-1) and the sensitivity is 0.0013 mugcm(-2) for an absorbance of 0.001.