Determination of aminopolycarboxylate complexes of transition metal (Mn²⁺, Cu²⁺ and Fe³⁺) in pulp by capillary zone electrophoresis (CZE-DAD)

[摘要] ENGLISH ABSTRACT:The determination of the concentrations of the transition metals Mn2+, Cu2+ and Fe3+in various types of pulps was carried out using a combination of chelation withEthylenediaminetetraacetic acid (EDTA) and ethylenediaminedisuccinic acid (S,SEDDS)and capillary zone electrophoresis (CZE) coupled with diode array uvdetection.The metals were found to be inhomogeneously distributed in the pulps, andtherefore a relatively large (20 gms) pulp samples were taken for analysis. Heating thepulp samples at 45°C with stirring for three hours was used to leach the metals intoan aqueous phase for complexation with the ligands. Leaching with EDTA enabledthe quantitative determination of 0.0091,0.0048 and 0.0014 mM Cu2+ and 0.0088,0.0012 and 0.0016 mM Mn2+ in the three types of pulps analyzed respectively whiledetection of Fe3+ was not possible using EDTA. The use of [S,S-EDDS] as theleaching agent on the other hand enabled the quantitative determination of 0.0041,0.0036 and 0.0031 mM Cu2+ and 0.0024, 0.0018 and 0.0047 mM Fe3+ in the threetypes of pulps analyzed respectively while determination of Mn2+ was not possibleusing [S,S-EDDS] as the leaching agent. [S,S-EDDS] was generally better incomplexing iron and copper than EDTA. The leaching procedure employed and thedetectors response to specific analytes formed were found to be the most importantfactors in the analysis of the metals in pulp.

[发布机构] Stellenbosch University