Comments on: "The effect of substituent groups on the reductive degradation of azo dyes by zerovalent iron" by M. Hou, et al. [J. Hazard. Mater. 145 (2007) 305]

This letter discusses possible improvements in experimental conditions to enable a purposeful discussion on the effect of substituent groups on the reductive degradation of azo dyes by elemental iron (Fe0) in a recent article by Hou and his co-workers. Also recalled is the pH dependence of the iron corrosion mechanism which is usually overlooked in the iron technology literature.

Kewyords: Adsorption; Azo dyes; Iron corrosion; Béchamp reduction