Jump to main content
Jump to site search


Metallic ion leaching from heterogeneous catalysts: an overlooked effect in the study of catalytic ozonation processes

Author affiliations

Abstract

Heterogeneous catalytic ozonation has been increasingly studied for the degradation and mineralization of refractory organic water pollutants in recent years. Compared with homogeneous catalysts, an important advantage of heterogeneous catalysts is that they can be easily separated from the treated water, making the process economically viable. While many studies have focused on the development and evaluation of metal oxide-based catalytic ozonation, possible leaching of metal ions and the subsequent effect on the contaminants' degradation are sometimes overlooked. Here, we examined metal leaching from several solid catalysts and further investigated the influence of the leached metal ions on the mineralization of two model compounds (oxalate and nitrobenzene) during continuous ozonation. Metallic ion leaching was observed from both commercially-available catalysts and catalysts prepared via wet-chemistry methods in the lab. The water matrix has been demonstrated to play an important role in metal leaching. The homogeneous catalytic effect resulting from the leached metal ions was found to be significant. A mechanism involving the formation of an unstable Cu(III)/oxalate complex through the reaction between ˙OH and Cu(II)/oxalate was proposed to explain the experimental observations. Our results indicate that the stability of the solid catalysts and the effects of the leached ions must be carefully examined during the catalytic ozonation of organic contaminants. Through this study we highlight the importance of rigorous, accepted protocols for evaluating and reporting heterogeneous catalyst performance in water/wastewater treatment within the research community.

Graphical abstract: Metallic ion leaching from heterogeneous catalysts: an overlooked effect in the study of catalytic ozonation processes

Back to tab navigation

Supplementary files

Publication details

The article was received on 26 Jul 2017, accepted on 15 Sep 2017 and first published on 02 Oct 2017


Article type: Paper
DOI: 10.1039/C7EW00273D
Citation: Environ. Sci.: Water Res. Technol., 2017, Advance Article
  •   Request permissions

    Metallic ion leaching from heterogeneous catalysts: an overlooked effect in the study of catalytic ozonation processes

    W. Yang, B. Vogler, Y. Lei and T. Wu, Environ. Sci.: Water Res. Technol., 2017, Advance Article , DOI: 10.1039/C7EW00273D

Search articles by author

Spotlight

Advertisements