Evaluation of Diazatetraoxa Cryptand as Extractant for Transition Metals and Pb2+

Abstract

The extractability of metal cations such as Mn²⁺, Co²⁺, Cu²⁺, Zn²⁺ and Pb²⁺ from aqueous phase to organic phase with 19-nitro-6,7,15,16,23,24-hexahydro-13H,26H-14,25-propanotribenzo-[b,I,o][1,4,11,14,7,18]-tetraoxadiazacycloikocine was investigated by means of UV-vis spectrophotometer. The aqueous phase and the organic phase contained metal picrate and the ligands, respectively. Chloroform and dichloromethane were the organic solvents. The effect of pH on the percent extraction was evaluated between 2.0 and 5.5 for both organic solvents. The range at which high percent extraction of the ligand was obtained was between pH 5.0 to 5.5 for both solvents. The most effective transport was observed for Mn2+ with 84.69 % picrate among the tested metal picrates with dichloromethane at pH 5.5. The extraction constant values (log K_ex) were determined for extracted metal complexes at the most effective extraction pH.