UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Explaining the interactions between metaldehyde and acidic surface groups of activated carbon under different pH conditions

Ferino-Pérez, A; Gamboa-Carballo, JJ; Li, Z; Campos, LC; Jáuregui-Haza, U; (2019) Explaining the interactions between metaldehyde and acidic surface groups of activated carbon under different pH conditions. Journal of Molecular Graphics and Modelling , 90 pp. 94-103. 10.1016/j.jmgm.2019.04.006. Green open access

[thumbnail of Ferino-Pérez et al UCL Discovery.pdf]
Preview
Text
Ferino-Pérez et al UCL Discovery.pdf - Accepted Version

Download (1MB) | Preview

Abstract

Metaldehyde (MA) is an organic compound widely used in agriculture all around the world as molluscicide. There are growing concerns that relatively high levels of MA have been detected in surface water, which could be ascribed to the fact that it is transparent to common wastewater treatment processes. A theoretical study of the influence of activated carbon (AC) surface groups (SGs) on MA adsorption is done in order to help to understand the process and to evaluate the influence of the acid SGs over the adsorption in AC filters. Multiple Minima Hypersurface methodology was employed in order to study the interactions of the MA with acid SGs (hydroxyl and carboxyl) at acidic and neutral pH, and at different hydration conditions explicitly taking into account the solvent influence. Selected structures were re-optimized using Density Functional Theory and posteriorly refined to achieve a well-defined electron density to characterize the interactions by the Quantum Theory of Atoms in Molecules approach. The obtained results showed that the presence of SGs enhances the adsorption process. The deprotonated carboxyl and hydroxyl SGs of AC models show the strongest interactions, suggesting greater adsorption at neutral pH which is in concordance with experimental data. The main interactions are of a dispersive nature between the pesticide and the π-cloud of the AC and hydrogen bonds between the MA and the acid SGs suggesting that the adsorption process is driven by a physisorption mechanism. Water acts as an intermediary between the AC and MA and competing with it for the adsorption sites.

Type: Article
Title: Explaining the interactions between metaldehyde and acidic surface groups of activated carbon under different pH conditions
Open access status: An open access version is available from UCL Discovery
DOI: 10.1016/j.jmgm.2019.04.006
Publisher version: https://doi.org/10.1016/j.jmgm.2019.04.006
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: Acidic surface group, Activated carbon, DFT, MMH, Metaldehyde, QTAIM
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Civil, Environ and Geomatic Eng
URI: https://discovery.ucl.ac.uk/id/eprint/10074425
Downloads since deposit
108Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item