Preconcentration and Spectroscopic estimation of Zn (II) by sensitive Cloud Point Extraction Technique using Imidazole Azo Reagent

Abstract

The organic reagent is using is [4 –CMePAI] ,the reagent was spectra methed by using (FT-IR), and (uv-vis) as an identification using  Spectrophotometric study for ion pair complex of Zn(II) ion extracted into cloud point extraction, appeared wave length of maximum absorbance was λ =447 nm for organic reagent, λ =470 nm for extracted Zn (II) ion as ion- pair association, laboratory produced novel azo the study about Determination the optimum extraction and determination conditions were pH = 8 in the presence of 100 μg Zn (II) in 10 mL aqueous solution, 0.5 mL Triton X-114, and heating temperature of 80 c° for 15 minutes, Theromdynamic parameters of CPE for extraction process of the ion –pair association complex in the triton X-114 were also considered ΔH= + 0.2627 kJ mol^-1, ΔG - 58.973 kJ mol^-1, ΔS= + 167.8 J mol^-1 K^-1 That referred endothermic reaction, with limit of Detection (LOD=0.3798 ppm ) and limit of quantitation (LOQ= 1.266 ppm) ,RSD%=0.362, Molar absorptivity (ℇ=43590Lmol^-1.cm^-1). stoichiometry shows the ion- pair complex extracted was 1:2  [Zn- 4 –CMePAI]⁺²:2Cl^-, in addition to study of  electrolyte effect and spectrophotometric determination of Zn(II) in different samples. The calibration curve linear  with correlation coefficient [Zn 4 –CMePAI]⁺²:2Cl^-  of r =0.999  .The proposed method applied for the determination of zinc in vegetables pills.