Nguyen Khanh Hoang
Industrial University of HoChiMinh City, Vietnam
Title: Spectrophotometric determination of Cr(iii) and Pb(ii) using 5,11,17,23-tetra[(2-ethyl acetoethoxyphenyl) (azo) phenyl]calix[4]arene
Biography
Biography: Nguyen Khanh Hoang
Abstract
New complexes of 5, 11, 17, 23-tetra[(2-ethyl acetoethoxyphenyl)(azo)phenyl]calix[4]arene (TEAC) with Pb(II) and Cr(III) were prepared in basic solution with a mixture of MeOH and H2O as solvent. The ratio of TEAC and metal ions complexation was found to be 1:1 under investigated condition. The complex formation constants (based on Benesi–Hildebrand method) for TEAC-Pb(II) and TEAC-Cr(III) were 4.03×104 and 1.2×104, respectively. Additionally, the molar extinction coefficients were 5×104 and 1.42×104 for TEAC-Pb(II) and TEAC-Cr(III), respectively. The H-point standard addition method (HPSAM) has been applied for simultaneous determination of complexes formation of Cr(III)/Pb(II) and TEAC with concentration from 2:1 to 1:20 (w/w). The proposed method was successfully utilized to invest lead and chromium content in plating wastewater samples. The results for several analyzed samples were found to be in satisfied agreement with those acquired by using the ICP-MS technique.