17 th International Conference on Environmental Science and Technology Athens, Greece, 1 to 4 September 2021 CEST2021_00211 Ultrasound-assisted Fenton-like degradation of methylene blue using electrospun nanofibrous membranes PERVEZ MN. 1 , STYLIOS GK. 2 , BUONERBA A. 1 , HASAN SW. 3 , CAI YJ. 4 , ZHAO YP. 5 , TALUKDER ME. 6 , SONG HC. 6 , ZARRA T. 1 , and NADDEO V. 1* 1Sanitary Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, via Giovanni Paolo II 132, 84084 Fisciano (SA), Italy 2 Research Institute for Flexible Materials, School of Textiles and Design, Heriot-Watt University, Galashiels, TD1 3HF, UK 3 Center for Membranes and Advanced Water Technology (CMAT), Department of Chemical Engineering, Khalifa University of Science and Technology, P.O. Box 127788 Abu Dhabi, UAE 4 Engineering Research Centre for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan Textile University, Wuhan, 430200, China 5 School of Ecological and Environmental Sciences, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration in East China Normal University, and Institute of Eco-Chongming, Shanghai 200062, China 6 Water Science Center, Guangzhou Institute of Advanced Technology, Chinese Academy of Sciences, Guangzhou, 514480, China *corresponding author: e-mail: vnaddeo@unisa.it Abstract. New materials supported by Green Chemistry have been receiving widespread attention because they are fulfilling the sustainable development goals (SDGs) agenda, for which clean water development is a top priority. Recently, electrospun nanofibers membranes are being frequently used to decontaminate organic pollutants such as dyes because of their easy operation, flexibility, economic feasibility and high removal efficiency. In the present study, green polyvinyl alcohol-based electrospun nanofibers membranes (PVA NF) were produced at room temperature and applied for efficient capturing methylene blue as a common organic pollutant. A series of experiments were conducted to affirm their catalytic activity. In particular, dye degradation studies were initiated by dissolving a selected amount of Fe (III), H2O2, PVA NF membrane and ultrasound (ULTS). Results showed that ultrasound could generate hydroxyl (•OH) radical and triggers dye removal percentages, which are of significant contribution in terms of peroxide- free Fenton-like catalysis. Finally, this study has proven that electrospun nanofibrous membranes could be a potential economic and efficient carrier for the Fenton catalytic process to capture large amounts of organic pollutants from industrial effluents. Keywords: Electrospun nanofiber membrane, Green Chemistry, clean water, Fenton-like, methylene blue 1. Introduction Dyes are considered as one of the major pollutants in wastewater because of their adverse effects on human health and the ecosystem. Methylene blue (MB) is a common dye used in various industrial sectors such as textile, food, paper, leather, etc. However, it is identified as highly toxic and carcinogenic (Kaya-Özkiper et al. 2021; Pervez et al. 2020a). Therefore, several technologies have been applied for the removal of MB from wastewater. Among them, electrospun nanofiber membranes exhibit great promises in wastewater treatment (e.g., dyes removal). This performance was obtained due to their high specific surface area, porosity, and removal efficiency (Hosseini et al. 2018; Pervez and Stylios 2018b). Usages of water-soluble polymers are getting attention for the fabrication of electrospun-based nanofibers membranes because of the following Green Chemistry principle, which are one of the potential requirements towards environmental sustainability development (Horzum et al. 2019; Pervez and Stylios 2018a; Rylkova et al. 2012). Polyvinyl alcohol (PVA) is a water-soluble polymer, and the PVA-based electrospun nanofibers membrane shows high chemical resistance, thermal and mechanical stability and hydrophilicity that makes them a suitable candidate for water treatment (Pervez et al. 2020c; Yin et al. 2020; Zhao et al. 2015). However, the dye removal performance of the pure electrospun nanofiber membrane could be moduled by the addition of a catalytic process. Fenton reaction has long been used to capture recalcitrant-based organic pollutants from wastewater due to its easy operation, rapid processing and high degradation efficiency (Liu et al. 2017; Pervez et al. 2019; Telegin et al. 2016). Fenton reaction mainly works on the generation of powerful hydroxyl (•OH) radicals, and in recent years, it is reported that ultrasound (ULTS) could generate •OH radicals and accelerate the Fenton reaction, Keeping in mind the above considerations, in this study, we proposed a robust dye removal process by the combination of ULTS-assisted nanofibers membrane and Fenton reaction. This work has paved the way to open up