Cloud Point Methodology to Determination Pb+2 by 4-CMePADPI Reagent Coupled with Spectrophotometry

Abstract

     A modern extraction method for separating, enriching and estimating Pb⁺² by using the CPE extraction technique and coupled with the spectrophotometry. For the purpose of determination Pb⁺², it was prepared in the laboratory of 2-[4-carboxymethylphenylazo]-4,5-diphenyl imidazole 4-CMePADPI as an organic reagent to formation complex with lead, which is extracted to the non-ionic surface TX-100 by the volume of 0.8 mL at 80^oC degree of the critical temperature needed to form a cloud point. Where the rich phase by lead complex is separated and dissolved in ethanol and is determined by spectrophotometric method at λ_max = 437 nm. The optimum pH = 9 and 30 μg / 5 mL of Pb⁺². The values of the thermodynamic functions for extracting the ion association complex of Pb⁺²ΔH_ex = – 0.005214 kJ, ΔS_ex = + 188.036 J, and ΔG_ex = – 66.382 kJ, as the study of the molar composition of the ion association complex obtained by following the slope analysis is (1:1). The method gave an enrichment factor 13.428 and a reconcentration’s 6.25.