| Summary: | This thesis consists of three parts. The first part provides an introduction to the calix[4]pyrroles and calix[4]arenes chemistry and their applications as ion selective electrodes for the determination of the mercury(II) ion in aqueous solution and as extracting agents for the removal of pollutants from water. The second part describes the experimental works carried out in the laboratory. The third part presents results, and discussion as follows: i. The compounds 5, 11, 17, 23-p-tetra-tert-butyl 25, 27 dihydroxy 26, 28-bis(2-ethoxymethoxy) calix[4]arene (L1), 5,11,17,23-tetra-tert-butyl 25,27-bis(diethylamino)ethoxy 26,28-(bis methoxyethoxy) calix[4]arene (L2) and mesotetramethyltetrakis-[(N,N-diethylacetamide)phenoxymethyl] calix[4]-pyrrole (CPA) dimer were successfully synthesised and characterised using different techniques. ii. The interaction of the receptors meso-tetramethyl-tetrakis-(4-hydroxyphenyl) calix[4]-pyrrole, (CPII), and mesotetramethyltetrakis-[(N,Ndiethylacetamide)phenoxymethyl] calix[4]-pyrrole (CPA), (previously synthesised) as well as L1 and L2 ligands with different metal cations in CD3CN at 298 K was investigated using the 1H NMR technique. It is concluded that CPA and L2 ligands interact with Li+, Na+, Ca2+, Sr2+, Ba2+, Cd2+, Zn2+, Pb2+ and Hg2+ cations whereas CP(II) and L1 ligands do not interact with cations tested. iii. Conductance and thermodynamic studies of complexing of CPA and L2 with metal cations in acetonitrile at 298.15 K were investigated with the Nano Isothermal Titration Calorimeter. iv. Complexation studies proved by 1H NMR, conductance and ITC techniques of CPA and metal cations in acetonitrile were compared to those previously reported in the Thermochemistry Laboratory. v. The ability of the CPA dimer for the removal of Hg2+, Pb2+, Zn2+, Cu2+ and Cd2+ ions from an aqueous solution was proved under different experimental conditions. vi. The preparation and characterization of Hg2+ ion selective membranes using different components based on CPA and L2 ionophores are described. Also, the influence of a number of experimental parameters and interferences on the response of the electrodes as well as analytical applications of these ISEs were studied.
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