São Luís, Brazil
São Luís, Brazil

Time filter

Source Type

Martiniano L.C.,LPQA LAPQAP UFMA | Martiniano L.C.,Federal University of Paraiba | Abrantes V.R.,LPQA LAPQAP UFMA | Neto S.Y.,LPQA LAPQAP UFMA | And 10 more authors.
Fuel | Year: 2013

A mercury film electrode was used to determine direct and simultaneously Pb(II) (at -410 mV) and Cu(II) (at -100 mV) in biodiesel by anodic stripping voltammetry. A linear response was obtained for Pb(II) and Cu(II) in the 2.00 × 10-8-1.00 × 10-7 mol L-1 concentration range and detection limits were 2.91 × 10-9 mol L-1 and 4.69 × 10-9 mol L-1 for Pb(II) and Cu(II), respectively, with recovery around of 100.0%. © 2012 Elsevier Ltd. All rights reserved.


Martiniano L.C.,LPQA LAPQAP UFMA | Martiniano L.C.,Federal University of Paraiba | Almeida J.M.S.,LPQA LAPQAP UFMA | Cavalcante G.H.R.,LPQA LAPQAP UFMA | And 9 more authors.
Current Analytical Chemistry | Year: 2014

An improved procedure is presented to determine Pb(II) and Cu(II) in gasoline using a mercury film electrode generated in situ. The method is based on the reduction of the metal ions at adequate potentials on the glassy carbon electrode, in whose optimized microemulsion medium composition, the ions can be determined directly and simultaneously by differential pulse anodic stripping voltammetry. Good results were obtained in terms of analytical performance and voltammetric wave forms, with two stripping peaks near to -0.420 V and -0.13 V, attributed to Pb(II) and Cu(II), respectively. Linear responses for both metal ions indicated quite low detection limits (2.1x 10-9 mol L-1 for Pb(II) and 2.4 x 10-9 mol L-1 for Cu(II)). The method was applied successfully to real gasoline samples, presenting good results for precision (variation coefficients of 12.4% and 10.2%) and accuracy (recoveries ranging from 96.7 to 99.33% and 101.33 to 102.67%), for Pb(II) and Cu(II), respectively. © 2014 Bentham Science Publishers.

Loading LPQA LAPQAP UFMA collaborators
Loading LPQA LAPQAP UFMA collaborators