Graphic Data Analysis and Complex Formation Curves as Modelling and Optimization Tools in Potentiometric and Voltammetric Speciation Studies of a Pb(TAPSO) x (OH) y System
2005; Wiley; Volume: 17; Issue: 14 Linguagem: Inglês
10.1002/elan.200403244
ISSN1521-4109
AutoresCarina M. M. Machado, Ignacy Cukrowski, Helena M. V. M. Soares,
Tópico(s)Advanced Chemical Sensor Technologies
ResumoAbstract The formation of complex species between lead and TAPSO, a commercialized biological buffer, was evidenced and discussed. Formation constants of Pb(TAPSO) x (OH) y system have been studied by direct current polarography and by glass electrode potentiometry at fixed total–ligand and total–metal concentration ratio and varied pH, at 25.0 °C and ionic strength set to 0.1 M KNO 3 . The graphic analysis revealed to be a very powerful tool in the prediction and refinement operations of Pb–(TAPSO) x (OH) y system. The proposed final model for this system is: PbL, PbL 2 , PbL 2 (OH) and PbL 2 (OH) 2 , with stability constants values, as log β , of 3.7±0.1, 6.6±0.1, 12.9±0.1 and 17.8±0.1, respectively.
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