The electrochemical mineralization of oxalic and oxamic acids using modified electrodes based on carbon nanotubes

• Type: Article in International Scientific Journal
• Date: 2013

Authors

M. Ferreira (Author) Other; M.F. Pinto (Author) Other; O.S.G.P. Soares (Author) FEUP; Manuel Fernando R Pereira (Author) FEUP; José Melo Orfão (Author) FEUP; José Luís Figueiredo (Author) FEUP; I.C. Neves (Author) Other; A.M. Fonseca (Author) Other; P. Parpot (Author) Other

Journal

Title: Chemical Engineering Journal

Vol. 228

Pages: 374-380

ISSN: 1385-8947

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 8 Citations

ISI Web of Science

Scopus - 11 Citations

Scientific classification

FOS: Engineering and technology

Other information

Authenticus ID: P-008-BBN

DOI: 10.1016/j.cej.2013.05.004

Abstract (EN): Constant current and constant potential electrolyses of oxalic and oxamic acids were carried out on multiwalled carbon nanotubes (CNT) and on monometallic (Pd and Pt) and bimetallic (Ru-Cu) catalysts supported on multiwalled carbon nanotubes. Both carboxylic acids were mineralized with high conversions via hypochlorite ion produced in situ, in 0.10 M NaCl medium. Highest current efficiency, corresponding to 97%, and highest reaction rate constant for oxalic acid mineralization were obtained for the Ru-Cu/CNT modified electrode, in 0.10 M NaCl medium. The mineralization of oxamic acid was achieved with a faradic yield of 96% and an energy consumption of 14.6 kWh (kg of pollutant)(-1) the same medium. The conversion values obtained for the oxidation of oxalic acid in 0.50 M NaOH medium, on Pt/CNT, Pd/CNT and Ru-Cu/CNT modified electrodes, were respectively 42%, 60% and 85%. In this last medium, 88% of the initial oxamic acid (15.8 mM) was transformed to carbonate ion and nitrogen at Pt/CNT modified anode.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7