Revealing the adsorption mechanism of copper on hemp-based materials through EDX, nano-CT, XPS, FTIR, Raman, and XANES characterization techniques

• Published in: Chemical engineering journal advances Vol. 10; p. 100282
• Main Authors: Mongioví, Chiara, Crini, Grégorio, Gabrion, Xavier, Placet, Vincent, Blondeau-Patissier, Virginie, Krystianiak, Anna, Durand, Sylvie, Beaugrand, Johnny, Dorlando, Angelina, Rivard, Camille, Gautier, Landrot, Ribeiro, Ana Rita Lado, Lacalamita, Dario, Martel, Bernard, Staelens, Jean-Noël, Ivanovska, Aleksandra, Kostić, Mirjana, Heintz, Olivier, Bradu, Corina, Raschetti, Marina, Morin-Crini, Nadia
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.05.2022; Elsevier
• Subjects: Adsorption; Copper; Engineering Sciences; Hemp shives; Mechanics; Mechanism; Other; Physics; Hemp shives; Adsorption; Copper; Mechanism
• ISSN: 2666-8211; 2666-8211
• DOI: 10.1016/j.ceja.2022.100282

•Activated (SHI-C) and grafted (SHI-BTCA) hemp-based samples were used for recovery copper from solutions.•Microscopic and spectroscopic techniques permit to distinguish the type of interactions involved in the phenomena•Various adsorption mechanisms for copper were discussed.•The main adsorption mechanism was surface adsorption and diffusion for SHI-C and ion-exchange and precipitation for SHI-BTCA. Hemp-based materials have been recently proposed as adsorbents for metals present in aqueous solutions using adsorption-oriented processes. This study aims to reveal the adsorption mechanism of materials prepared from hemp shives as co-products of the hemp industry, namely sodium carbonate-activated (SHI-C) and polycarboxylic agent-grafted (SHI-BTCA) hemp shives. The interactions between copper and two hemp-based materials were characterized by different microscopic and spectroscopic techniques such as energy-disperse X-ray (EDX) spectroscopy, computed nano-tomography (nano-CT), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, and X-ray absorption near-edge structure (XANES) spectroscopy. The results showed remarkable different mechanisms for copper adsorption onto the SHI-C and SHI-BTCA hemp shives. Namely, copper surface adsorption and diffusion in the structure of the SHI-C material were predominant, whereas the adsorption of copper onto SHI-BTCA was due to a chemisorption phenomenon and ion-exchange involving the adsorbent carboxylate groups. The combination of the abovementioned complementary microscopic and spectroscopic techniques allowed us to characterize and distinguish the type of interactions involved in the liquid-solid adsorption phenomena. [Display omitted]