Affordable Access

Decoloration of orange G (OG) using electrochemical reduction.

Authors
  • Khenifi, Aicha
  • Bouberka, Zohra
  • Hamani, Houari
  • Illikti, Hocine
  • Kameche, Mostefa
  • Derriche, Zoubir
Type
Published Article
Journal
Environmental Technology
Publisher
Informa UK (Taylor & Francis)
Publication Date
2012
Volume
33
Issue
7-9
Pages
1081–1088
Identifiers
PMID: 22720437
Source
Medline
License
Unknown

Abstract

The electrocatalytic hydrogenation of Orange G is investigated using spectrophotometric experiments in laboratory cells. The working electrode consists of a thin grid coated with a layer of nickel in which fine particles of Raney nickel are dispersed. The optimal conditions of decoloration are as follows: basic pH, 0.05 g/L of dye concentration and 0.05 A of current density. Under these conditions, the OG decoloration efficiency reached 100% after only 1800 s of reaction. The observed values of the maximum absorbance in the spectra of the reaction mixture fitted well the polynomials of the fifth degree with respect to reaction time. The initial degradation rate of the dye is obtained easily as the differential coefficient of the functions at initial time. The degradation rate of the dye in the initial stage of the reaction is given by the first-order rate equation. The instantaneous current efficiency was calculated and the results indicated that cathodic reduction was the main contributor to the decoloration of OG. Direct cathodic reduction ofazo dyes allows decolorization of intensively coloured textile wastewater without addition of chemicals or formation of sludge. The technique is of particular interest for the treatment of concentrated dye baths. The effect of current density, dye concentration, and concentration and nature of the supporting electrolyte on the reduction of the Orange G are reported.

Report this publication

Statistics

Seen <100 times