Editor’s Choice – Degradation of the O-phenylphenol Fungicide in Water by Unconventional CeO2-WO3 Photocatalysts

Author(s):Roberto Fiorenza, Stefano Andrea Balsamo and Salvatore Scirè*

Volume 2, Issue 3, 2021

Published on: 16 August, 2021

Page: [234 – 242]

Pages: 9

DOI: 10.2174/2665976X02666210816113433

Abstract

Background: Water pollution due to emerging contaminants such as pesticides, pharmaceutics and/or plasticizers, is a serious environmental problem strictly connected to the safety of human and ecosystem life. For this reason, the development of high-performing (photo)catalysts for water purification is crucial.

Objective: In recent years, the synergistic effects in Advanced Oxidation Processes (AOPs) can perform better strategies to remove recalcitrant contaminants from water. In this context, the (photo) catalytic activity of CeO2-WO3 materials for the degradation of the orto-phenylphenol fungicide comparing the photocatalytic, the Fenton and the photo-Fenton-like processes, has been examined.

Methods: The samples were synthetized through deposition-precipitation mediated with the hexamethylenetetramine (HMTA) surfactant. The chemico-physical properties of the materials were examined by Raman, UV-Vis Diffuse Reflectance (Uv-vis DRS) and X-Ray photoelectron (XPS) spectroscopies, N2 adsorption-desorption measurements and transmission electron microscopy (TEM). The (photo)catalytic measurements were made through a home-made photoreactor irradiated by a solar lamp. The degradation of the fungicide was measured by UV-vis spectroscopy.

Results: An efficient heterojunction was formed between the CeO2 and the WO3 oxides, which provided a good degradation percentage of the pesticide (65%) employing the solar photo-Fenton-like reaction that was the best performing process among the three investigated AOPs. The addition of WO3 on CeO2 facilitated the ionic exchange between the Ce and the W ions, boosting the redox properties of cerium oxide.

Conclusion: The strong interaction between CeO2 and WO3 and the peculiar properties of this unconventional composite pave the way to its use as a promising material for water depollution. Read now: https://bit.ly/3ppJuLQ

MOST ACCESSED ARTICLE – A Review on Chemical Advanced Oxidation Processes for Pharmaceuticals with Paracetamol as a Model Compound. Reaction Conditions, Intermediates and Total Mechanism

Journal Name: Current Organic Chemistry

Author(s): Elisa Leyva*, Edgar Moctezuma, Kim M. Baines, Saul Noriega, Elvira Zarazua.

 

 

 

Graphical Abstract:

 

 

Abstract:

Background: In recent years, there has been a growing interest in the environmental relevance of the presence of several pharmaceutical compounds and their metabolites in water. To avoid further accumulation of these compounds and their metabolites in the aquatic environment, several research groups are investigating chemical and photochemical methods that could be applied in their destruction and subsequent removal from natural and wastewater.

Objective & Method: Different chemical advanced oxidation processes are being developed to destroy organic pollutants in water. Most of these methods are based on the production of HO• radicals that are known to be highly reactive and strong oxidizing agents. In aqueous chemical processes, these radicals can be generated using a variety of reagents and under different reaction conditions such as O3, H2O2/UV, TiO2/UV, O3/UV, H2O2/Fe2+, H2O2/Fe2+/UV and O3/Fe2+/Cu2+/UV. This review is a survey on recent advances in the application of different chemical advanced oxidation processes to mineralize pharmaceuticals. Paracetamol was selected as a model compound since its structure is the main component or metabolite of several anesthetic and analgesic compounds. The degradation of paracetamol by different advanced oxidation methods has been investigated by a combination of techniques (TOC, UV-Vis, IR, HPLC and GC-MS) in order to determine the optimal reaction conditions, kinetics, intermediate and product compounds generated.

Conclusion: Understanding the basic concepts about reaction conditions, intermediates and mechanistic details on mineralization of paracetamol will be quite useful for future applications of several techniques in the removal of this and other structurally related pharmaceutical and aromatic compounds from water.

 

READ MORE HERE: http://www.eurekaselect.com/156477