Separation of Co(II), Ni(II), Cu(II) and Pd(II) with 4-benzoyl-3-methyl- 1-phenylpyrazol-5-one using tetradecyldimethylbenzylammonium chloride-naphthalene as an adsorbent

Abstract

A method has been established for the determination of Co(II), Ni(II), Cu(II) and Pd(II) after preconcentration with 4-benzoyl-3-methyl-1-phenylpyrazol- 5-one (BMPP) supported on tetradecyldimethylbenzyl ammonium chloride (TDBA)-microcrystalline naphthalene using a simple funnel-tipped glass tube. The metals form a water insoluble metal-BMPP complex with <i>λ</i>_max at 360 nm for Co(ll), 480 nm for Ni(ll), 430 nm for Cu(II) and 380 nm for Pd(II)-complexes. The molar absorptivities and Sandell's sensitivities for all these complexes are found to be in the range 1.09 x 10⁴-1.87 x 10⁴ l mol^-1 cm^-1 and 0.0046- 0.0058 <i> µg </i> cm^-² respectively. The proposed method has been tested for the determination of nickel(ll) and copper(II) in standard alloys and vehicle exhaust particulates.