Preparation Of New Polydentate Ligand And Determination Of Metal By HPLC After Cloud Point Extraction

Cloud point extraction （CPE） is a new liquid-liquid extraction technology which hasbeen proved to have many advantages,such as small environmental impacts,convenientoperation,high speed,high concentration rate,less solvent consumption etc,therefore it hasbeen widely used in environmental monitoring,food industry,biological sample analysis,metal detection etc.Chelator is the core of extraction technology which should have highselectivity and strong chelating ability,organic ligand chelating metal ions has good promisingapplications.2-mercapto-4-amino-6-hydroxy pyrimidine was prepared from ethylcyanoacetate by the reactions of cyclization,adding sodium ethoxide and thiourea to it;Then2-mercapto-4-amino-5-nitroso-6-hydroxy pyrimidine was synthesized by the reaction ofnitrosylation,using sodium dithionite deoxidized2-mercapto-4-amino-5-nitroso-6-hydroxypyrimidine,2-mercapto-6-hydroxy-4,5-diamino pyrimidine was synthesized.The polydentateligand with functional group atoms of N,O,S can form coordinate-covalent bond with metalion and form stability of the metal chelate.The structure was characterized by FT-IR,SEM,NMR.The hydrophobic metal chelates were formed by chelating Cu²⁺,Hg²⁺,Fe³⁺in thewater.The cloud point property of the nonionic surfactant was used to extracte the chelatesfrom the water and then with high performance liquid chromatography to determine theextractants.In the range from0.2¹.0mg/L,the relationship between the peak area and theconcentration of Cu²⁺,Hg²⁺and Fe³⁺were linear,the coefficient correlations were0.9984,0.9983,0.9990respectively;the relative standard deviations of Cu²⁺,Hg²⁺,Fe³⁺were2.42%,3.56%,4.35%;the limits of detective were3.4μg/L,3.7μg/L,1.6μg/Lrespectively.Polydentate ligand has good effect on Cu²⁺,Hg²⁺,Fe³⁺in the water,extraction rateis more than94%.