CHEMICAL ENGINEERING TRANSACTIONS VOL. 73, 2019 A publication of The Italian Association of Chemical Engineering Online at www.aidic.it/cet Guest Editors: Andrea D’Anna, Paolo Ciambelli, Carmelo Sunseri Copyright © 2019, AIDIC Servizi S.r.l. ISBN 978-88-95608-70-9; ISSN 2283-9216 Non-Thermal Plasma Technology for the Effective Regeneration Of Macroscopic Adsorbent Materials Used In The Removal Of Patent Blue V Dye From Aqueous Solutions Giuseppina Iervolino, Olga Sacco, Vincenzo Vaiano*, Vincenzo Palma Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano (SA), Italy In this work, two different commercial macroscopic adsorbent materials (Na-ZSM5 zeolite in spherical pellets and TiO 2 cylindrical pellets) has been tested in the removal of model organic food dyes (Patent blue V, E131) and they were regenerated using an innovative techniques based on non-thermal plasma process. The adsorption experiments were carried out using a pyrex cylindrical reactor and liquid samples were analyzed in continuous mode by spectrophotometric measurement at λ = 636 nm. The results demonstrated that these materials were able to remove Patent blue V dye, with removal efficiency equal to 80% for the zeolite and 95% for TiO 2 pellets after 400 min of treatment time. The adsorbent materials have been used for several cycles until their saturation. In particular, after seven adsorption cycles, the adsorbing capacity was reduced of about 60 and 20% for zeolite and TiO 2 pellets, respectively. Subsequently, the materials were regenerated by non- thermal plasma and reused in the adsorption system. The results evidenced that the regeneration by non- thermal plasma was able to induce the complete degradation of the absorbed organic substance and consequently restoring the initial adsorption capacity of both macroscopic adsorbent materials. 1. Introduction Human, domestic and industrial activities require the use of a large amount of water. The direct consequence of this use is the production of wastewater. Therefore, it is necessary to purify the wastewater through processes able to remove the persistent contaminants that are among the main causes of problems in the aquatic ecosystem. In particular, dyes coming from textile and food industries are important pollutants in water effluents (Vaiano et al., 2016). Food dyes are one of the most widely used and dangerous additives in food industry (beverages, jelly sweets, candies, ice-cream, etc.). Approximately 10–20% of the dyes are lost during manufacturing process, resulting in large amounts in wastewater (Gao et al., 2011). The occurrence of food dyes residues in wastewater affects aquatic environment by colouring water and impeding light penetration. Moreover, they are suspected to cause carcinogenic effects, hypersensitivity reactions, and genotoxic effects on human health (Zhou et al., 2014). One of the food dyes most difficult to remove from wastewater and particularly subject to studies on the effects on human health is Patent blue V. It is a dark blue synthetic food dye and it has been banned in Australia, America and Norway since it can cause allergic reactions, with symptoms such as pruritus, skin rash, nausea and hypotension (Šafařı ́ k and Šafařı ́ ková, 2002). Furthermore, the release into the water environment of this dye causes serious environmental damage (Šafařı ́ k and Šafařı ́ ková, 2002), and for this reason, the removal of this dye is thus of primary concern and needs special attention (Bangash and Alam, 2006). Because of the low biodegradability of dyes, conventional biological treatment processes are not very effective in the removal of dyes from wastewater (Mafra et al., 2013, Li et al., 2017). Therefore, chemical and chemical-physical processes (e.g., coagulation, flocculation, adsorption, chemical oxidation) are typically used in food dyes wastewater treatment (De Caprariis et al., 2018). Adsorption is a widely used technology for wastewater purification. This process is based on the mass transfer of the contaminant: in this way the solid material (the adsorbent) can remove the dissolved contaminants present in the water by attracting them on its surface. Therefore, it involves the interphase accumulation of concentrated substances at a surface or at the interphase. This separation technique finds wide application in the removal of dye from aqueous media (Brahim et al., 2014). Consequently, materials such as activated 151 DOI: 10.3303/CET1973026 Paper Received: 30 March 2018; Revised: 05 August 2018; Accepted: 28 February 2019 Please cite this article as: Iervolino G., Sacco O., Vaiano V., Palma V., 2019, Non-thermal Plasma Technology for the Effective Regeneration of Macroscopic Adsorbent Materials Used in the Removal of Patent Blue V Dye from Aqueous Solutions , Chemical Engineering Transactions, 73, 151-156 DOI:10.3303/CET1973026