Estudo Teórico do Mecanismo de Complexação do Íon Cobalto II com a Glucosamina Usando Dinâmica Molecular de Car-Parrinello

Cobalt II is essential for the body and is one of the components of vitamin B12. However, in excess, it is toxic. It is present in various industrial and nuclear reactor waste; removing it is necessary. Among the various processes for removing heavy metals from wastewater, adsorption stands out, economical, easy to apply, and efficient. Modified chitosan has shown promise in the adsorption of cobalt II from contaminated waters. Although experimental studies show cobalt II adsorption by chitosan, the adsorption mechanism by chitosan is still unclear. This work aimed to study cobalt coordination with glucosamine (chitosan monomer) in the gas phase and aqueous solvation using the Car-Parrinello Molecular Dynamics. The results show that cobalt can coordinate strongly with the amino group of glucosamine in both the gaseous and aqueous environments. The QTAIM analysis was performed to characterize the interactions. In the gas phase, a partially covalent interaction was observed, while in the aqueous medium, the interaction of Co with glucosamine can be classified as covalent. Understanding the coordination mechanism of cobalt II with glucosamine can help remove cobalt from wastewater.