BERGAMOT POMACE ADSORBENT MATERIAL FOR THE REMOVAL OF HEAVY METAL IONS FROM AQUEOUS SOLUTIONS

In the last years, citrus processing waste has been used as a second raw material for multifunctional materials development capable of effectively and selectively interacting with organic pollutants, such as pesticides (POPs) as well as inorganic pollutants like metals and anions [1], through adsorption mechanisms. This contribution presents the preliminary results of an investigation focused on the potential of materials derived from bergamot citrus industry waste to be used as sequestrant agents [2] for metal ions in multicomponent solutions that simulate natural fluids conditions. After confirming the presence of functional groups capable to interact with metal ions through FT-IR ATR spectroscopy, potentiometric measurements were carried out at t = 25 °C and in an ionic strength range between 0.1-1 mol L-1 in NaNO3(aq). This technique allowed for the evaluation of pomace acid-base properties and the experimental data were analyzed using the Focus model [3]. To assess the adsorption selectivity of the material obtained, batch experiments were performed on a multicomponent solution containing Pb (II), Cd (II), Cu (II), Zn (II), and Ni (II) ions [4]. The concentration of each ion was determined by ICP-MS. Moreover, release experiments were carried out to assess the potential reuse of the material. Various desorbent agents (HCl, HNO3, GLDA, EDDS) were used to extract the metal cations [5]. Such as use of citrus processing waste as a second raw material offers a sustainable and environmentally friendly approach to address pollution challenges by transforming waste into functional materials for pollutant remediation. References: 1. Mahato N., …. & Cho K., Journal of Advanced Research 23 (2020) 61–82. 2. Schiewer S., & Pati S. B, Journal of Hazardous Materials 157 (2008) 8–17 3. Smith D.S., & Ferris F. G., Environmental Science & Technology 35 (2001) 46377-42. 4. Chu L., ... & Luo S., Journal of Hazardous Materials.300 (2015) 153–160. 5. Schiewer S., & Njikam E., Journal of Hazardous Materials 213-214 (2012) 242-248.