Química Nova (Jan 2007)
Determinação voltamétrica por redissolução anódica de Cu(II) em águas residuárias empregando um eletrodo de pasta de carbono modificado com quitosana Anodic stripping voltammetric determination of copper (II) in wastewaters using a carbon paste electrode modified with chitosan
Abstract
The electrochemical applications of a CPE modified with chitosan for the determination of Cu(II) in wastewater samples using anodic stripping voltammetry are described. The best voltammetric response was observed for a paste containing 25% m/m of chitosan. A 0.10 mol L-1 NaNO3 solution (pH 6.5) as supporting electrolyte, a pre-concentration potential of -0.20 V, pre-concentration time of 270 s and a scan rate of 25 mV s-1 were selected. The calibration graph was linear in the Cu(II) concentration range from 2.0 x 10-7 to 7.4 x 10-6 mol L-1, with a detection limit of 8.3 x 10-8 mol L-1.
Keywords