Theoretical study of the adsorption capacity of potentially toxic Cd²⁺, Pb²⁺, and Hg²⁺ ions in hemicellulose matrices

Author(s)

Gomes, Ellane Jacqueline Coelho Moreira ; Macedo, Vinicius Souza ; Pereira, Anna Karla dos Santos ; Cavallini, Grasiele Soares ; Pereira, Douglas Henrique

• Document type: Journal article
• Source: International Journal of Biological Macromolecules; v. 258, p. 9-pg., 2023-12-22.

Abstract

Hemicellulose is widely available in nature, is a sustainable resource and has a wide range of applications. Among them, adsorption stands out for the removal of potentially toxic ions. Thus, in the study, the adsorption of Cd2+, Pb2+ and Hg2+ ions in two hemicellulose matrices were elucidated through computational simulations using density functional theory. Molecular electrostatic potential and frontier molecular orbitals demonstrated whether the interactions could happen. Four interaction complexes were highlighted due to the interaction energy criteria, Delta E-Bind, Delta H and Delta G < 0.00 kcal mol(-1), that is: Hm1(& mldr;) Pb (1); Hm2(& mldr;) Pb (3); Hm2(& mldr;)Cd (4) and Hm2(& mldr;)Hg (4) and the results show that they occur through physisorption. In structural parameter studies, interaction distances smaller than 3000 & Aring; were identified, which ranged from 2.253 & Aring; to 2.972 & Aring;. From the analysis of the topological parameters of QTAIM, it was possible to characterize the intensities of the interactions, as well as their nature, which were partially covalent or electrostatic in nature. Finally, based on the theoretical results, it can be affirmed that the hemicellulose can interact with Cd2+, Pb2+ and Hg2+ ions, evidencing that this study can support further experimental essays to remove contaminants from effluents. (AU)

• FAPESP's process: 13/08293-7 - CCES - Center for Computational Engineering and Sciences
• Grantee: Munir Salomao Skaf
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 17/11485-6 - Computational and theoretical developments based on ab initio methods and the Density Functional Theory
• Grantee: Rogério Custodio
• Support Opportunities: Regular Research Grants