Advanced Oxidation Processes Coupled with Nanomaterials for Water Treatment

Abstract

Water quality management will be a priority issue in the near future. Indeed, due to scarcity and/or contamination of the water, regulatory frameworks will be increasingly strict to reduce environmental impacts of wastewater and to allow water to be reused. Moreover, drinking water quality standards must be improved in order to account for the emerging pollutants that are being detected in tap water. These tasks can only be achieved if new improved and sustainable water treatment technologies are developed. Nanomaterials are improving the ongoing research on advanced oxidation processes (AOPs). This work reviews the most important AOPs, namely: persulfate, chlorine and NH2Cl based processes, UV/H2O2, Fenton processes, ozone, and heterogeneous photocatalytic processes. A critical review of the current coupling of nanomaterials to some of these AOPs is presented. Besides the active role of the nanomaterials in the degradation of water contaminants/pollutants in the AOPs, the relevance of their adsorbent/absorbent function in these processes is also discussed.

Copper(II)-Doped Carbon Dots as Catalyst for Ozone Degradation of Textile Dyes

“…Nanomaterials have been coupled with ozone (catalytic ozonation) to eliminate or reduce the number of chemical substances involved in these treatments while increasing the pollutant degradation yields and reducing environmental impacts [ 10 , 11 , 12 , 13 ]. Taking into consideration natural resources, environmental sustainability and toxicity issues, carbon-based nanomaterials are preferred to metallic/semi-metallic materials in real-world applications [ 14 ].…”

UV-Based Advanced Oxidation Processes of Remazol Brilliant Blue R Dye Catalyzed by Carbon Dots

“…About 80% of the global emissions of this industry are discharged into environmental water, and, although textile effluents are constituted by a huge number of chemical substances, natural fibers, and microplastics, of greater concern are the large amount of non-biodegradable organic compounds, especially textile dyes [4,5]. The treatment of these substances in wastewaters requires advanced oxidation processes (AOPs) [6]. One of the types of AOPs that can be used for the degradation of selected pollutants present in wastewater is based on ultraviolet light (UV); that is a standard technology for water disinfection, but it can also be coupled to several other chemical systems, such as, for example, hydrogen peroxide and persulfate anion, enhancing the performance in AOP [7,8].…”

“…Nanomaterials are being coupled with UV-based AOP to make treatment processes more sustainable, i.e., to eliminate or reduce the amount of chemical substances involved in those processes, while increasing the pollutants degradation yields [6]. Taking into consideration natural resources, environmental sustainability, and toxicity issues, carbonbased nanomaterials are being preferred to metallic/semi-metallic materials in real-world applications [19].…”

Removal of Organics from Landfill Leachate by Heterogeneous Fenton-like Oxidation over Copper-Based Catalyst

“…However, there is a growing need for the development of new catalysts with extended recyclability, improved activity, and selectivity which can ultimately be employed in Fentonlike treatment. The organic abatement efficiency of a Fenton-like process can substantially be enhanced by replacing Fe with other transition metals as a catalytic source [28][29][30][31][32][33]. One good replacement is copper impregnated over appropriate supports.…”