Photoelectrocatalytic Oxidation of Cu-cyanides and Cu-EDTA at TiO2 nanotube electrode

Abstract

A B S T R A C TOxidation of Cu-cyanides and Cu-EDTA complexes by a photoelectrocatalytic process was investigated at the TiO 2 nanotube matrix electrode. The results indicated that Cu oxides were deposited onto the TiO 2 nanotube anode in the individual oxidation of Cu-cyanide complexes with the conversion of CN À into OCN À . In the case of Cu-EDTA, Cu-EDTA was efficiently oxidized at the TiO 2 nanotube anode and liberated Cu 2+ was deposited onto the cathode with only little amount of Cu oxides deposited onto the TiO 2 nanotube anode. The above reactions favored at acid conditions. Furthermore, simultaneous oxidation of Cu-cyanide and Cu-EDTA was performed at the

N and F Codoped TiO2 Thin Films on Stainless Steel for Photoelectrocatalytic Removal of Cyanide Ions in Aqueous Solutions

“…This is associated with the generation of electron-hole pairs on the surface of the semiconductor 5,38 . As it has been previously reported in the literature 5,[22][23][24] , photocatalytic oxidation of CNon TiO 2 occurs primarily due to direct charge transfer. 64% CNdegradation after 2 hr.…”

“…Nonetheless, the mechanisms of action of N and F as doping agents in TiO 2 are strongly dependent on the methods for the synthesis and preparation of the photocatalysts. Furthermore, even though the use of this type of semiconductor materials for the photoelectrocatalytic oxidation of cyanide represents a promising technology for the decontamination of natural water sources, it has hardly been investigated 5,22 . To our knowledge, the studies reported in the literature primarily deal with the electrooxidation of CNby direct electron transfer 23,24 using expensive electrodes, which compromises the economical feasibility of the process.…”

Effects of Four Carboxyl-Containing Additives on Imitation Gold Electroplating Cu-Zn-Sn Alloys in an HEDP System

“…Hg|HgO is mainly the dissolution peak of the Cu anode. There is also an anode dissolution peak E at 1.0 V vs. Hg|HgO, which is the oxidation peak of water [32][33][34][35][36][37]. With the increase in the SC content, the intensities of the deposition peaks A, B, and C all increased gradually, indicating that increasing the amount of this additive is beneficial to metal deposition.…”

Photoelectrocatalytic oxidation of metal-EDTA and recovery of metals by electrodeposition with a rotating cathode

“…The concentration of Cu complexes was tested using a high performance liquid chromatograph (HPLC, 1260, Agilent Technology) with the Hypersil Gold (Thermo Scientific) analytical column, the elution comprised of 8% acetonitrile (v/v)/92% oxalic acid (15 mM) (at pH 3.0, flow rate: 1 mL/min, 25°C, 254 nm) [24]. The total metal ions concentrations in the solution were measured by ICP-OES (700 series Agilent Technology, U.S.A).…”