cordierite and metolachlor

Emerging micropollutants have been recently the target of interest for their potential harmful effects in the environment and their resistance to conventional water treatments. Catalytic ozonation is an advanced oxidation process consisting of the formation of highly reactive radicals from the decomposition of ozone promoted by a catalyst. Nanocarbon materials have been shown to be effective catalysts for this process, either in powder form or grown on the surface of a monolithic structure. In this work, carbon nanofibers grown on the surface of a cordierite honeycomb monolith are tested as catalyst for the ozonation of five selected micropollutants: atrazine (ATZ), bezafibrate, erythromycin, metolachlor, and nonylphenol. The process is tested both in laboratorial and real conditions. Later on, ATZ was selected as a target pollutant to further investigate the role of the catalytic material. It is shown that the inclusion of a catalyst improves the mineralization degree compared to single ozonation.

Topics: Acetamides; Atrazine; Bezafibrate; Carbon; Catalysis; Ceramics; Erythromycin; Nanofibers; Oxidants; Ozone; Phenols; Waste Disposal, Fluid; Water Pollutants, Chemical

The catalytic ozonation of the herbicide metolachlor (MTLC) was tested using carbon nanomaterials as catalysts. Multiwalled carbon nanotubes were used in semi-batch experiments and carbon nanofibres grown on a honeycomb cordierite monolith were tested in continuous experiments. The application of the carbon catalyst was shown to improve the mineralization degree of MTLC and to decrease the toxicity of the solution subject to ozonation. Degradation by-products were also followed in order to compare the two processes. The application of the carbon coated monolith to the continuous ozonation process was shown to have potential as it improved the TOC removal from 5% to 35% and decreased the inhibition of luminescent activity of Vibrio Fischeri from 25% to 12%.

Topics: Acetamides; Aliivibrio fischeri; Catalysis; Ceramics; Herbicides; Luminescence; Nanofibers; Nanotubes, Carbon; Oxidants; Ozone; Water Pollutants, Chemical; Water Purification