Abstract

Shawket Kadhim Jawad¹, Safa Majeed Hameed¹ and Sahar Aqeel Hussain²

DOI : http://dx.doi.org/10.13005/ojc/330535

Extracted Mg(II) and Ca(II) each one alone after combined with EDTA (H₃Y^-) as (MgHY^-) and (CaHY^-) after preparing ion pair complexes according to liquid ion exchange method by using Cinchonine (CK) after changing to liquid ion exchanger HCK⁺;Cl^- in HCl medium, spectrophotometric studies showed that the ion pair magnesium complex HCK⁺;MgHY^- had a wave length for maximum absorbance of λ_max=241nm, but the maximum absorbance for calcium HCK⁺;CaHY^- was λ_max=278nm to determine the remaining quantity of Mg(II), the Eriochrome black T method was used, but for Ca(II) the crown ether DB18C6 method was used as new spectrophotometric method. Limitations to the study include optimum conditions for extraction ions in this study show a need for 1M HCl for Mg(II) and 0.8M HCl for Ca(II), to be present 100µg for each ion, 0.08M EDTA for Mg(II) and 1.0M EDTA for Ca(II), 1×10^-4M CK, after shaking for 10min.  Thermodynamic study shows ΔH_ex=0.058kJmol^-1, ΔG_ex =-47.28 kJmol^-1, ΔS_ex=158.86J.mol^-1. K^-1 for Mg(II) and for Ca(II) was ΔH_ex=0.0892kJmol^-1, ΔG_ex=-54.66 kJmol^-1, ΔS_ex=180.69J.mol^-1.K^-1.

Calcium; Magnesium; EDTA; Cinchonine; Liquid Ion Exchange; Solvent extraction

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