Electrochemical decolourisation of Reactive Orange 16 was carried out in an electrochemical flow-cell, using as working electrodes
a Pt thin film deposited on a Ti substrate (Pt/Ti) prepared by the Pechini method and a pure platinum (Pt) foil. Using the
Pt/Ti electrodes better results for dye decolourisation were obtained under milder conditions than those used for pure Pt.
For the Pt electrode, colour removal of 93 % (λ = 493 nm) was obtained after 60 min, at 2.2 V vs. RHE, using 0.017 mol L
−1 NaCl + 0.5 mol L
−1 H
2SO
4 solution. For the Pt/Ti electrode there was better colour removal, 98%, than for the Pt electrode. Moreover, we used 0.017 mol L
−1 NaCl solution and the applied potential was 1.8 V. Under this condition after 15 min of electrolysis, more than 80% of colour
was removed. The rate reaction constant, assuming a first order reaction, was 0.024 min
−1 and 0.069 min
−1, for Pt and Pt/Ti electrodes, respectively.
Keywords Electrochemical decolourisation - Reactive dye - Polymeric precursor method - Pt electrode