Adsorption of Phenolic Organic Pollutants on Graphene Oxide: Molecular Dynamics Study

Abstract

In this work, molecular dynamics (MD) simulations were applied to address the major concerns about the independent and competitive adsorption processes of phenolic organic pollutants (POPs) on the graphene oxide (GO) in aqueous solution. Phenol, α-naphthol and 4-octyl-phenol were adopted as representatives of POPs and their adsorption energies were calculated, which followed an order of 4-octyl-phenol (41.34 kJ/mol)>α-naphthol (33.23 kJ/mol)> phenol (19.31 kJ/mol). The simulation results showed that hydrophobic properties of POPs were recognized as the driving force for their adsorption behaviors. Moreover, van der Waals interaction, electrostatic interaction, as well as hydrogen bonds, may also improve the adsorption capacity of GO towards POPs. The competitive adsorption process revealed that in addition to the direct adsorption onto the GO surface, the molecular aggregation may be another indirect adsorption way existed in the mixed system. Understanding the interaction between GO and POPs in aqueous so

Efficient elimination of organic and inorganic pollutants by biochar and biochar-based materials

“…4d, the calculated potential energies in the order of 4-octyl-phenol (9.89 kcal/mol) > α-naphthol (7.95 kcal/mol) > phenol (4.62 kcal/mol) was consistent with the hydrophobic areas in Fig. 4c (Zhao et al 2019b). Further analyses of the MD results indicated that the aggregation and competitive adsorption were verified to be universally involved in the adsorption behavior of organic pollutants.…”

“…More recently, there has been a growing number of publications focusing on the theoretical approaches that have been applied to study processes involving graphene-based materials, including their structure, electronic properties, associations, behavior, as well as the interaction mechanisms (Ai et al 2019;Liu et al 2019c;Song et al 2016;Wei et al 2019;Zhao et al 2019b;Yu et al 2016Yu et al , 2017. This session will review recent research into the density functional theory (DFT) method and molecular dynamics (MD) calculations using graphene-based nanomaterials as example.…”

“…Interaction of Hg with biochar to form Hg-Cl and Hg-S bonds (b) (Liu et al 2018). The hydrophobic areas of phe-nolic organic pollutants in GO system (c) and potential of mean force (PMF) for phenol organic compounds in GO system (d) (Zhao et al 2019b) DFT-based computational approach in several aspects (Ai et al 2019;Wei et al 2019). First, the geometric optimization and binding energy calculations appear to be a major contributing factor and are closely linked to the adsorption mechanism.…”

“…Through dynamic analysis such as radial distribution functions (RDF), interaction energy, maximal cluster size, and hydrogen bonds, the MD simulation provides new quantitative insights into the interaction between carbonbased materials and pollutants. The adsorption mechanism of GO toward a series of organic pollutants, such as phenolic pollutants (Zhao et al 2019b), chlorophenol-based environmental hormones (Wei et al 2019) and tetracycline antibiotics (Ai et al 2019), and aromatic compounds, has been studied using MD simulations (Tang et al 2018a, b). The hydrophobic property was recognized as the driving force for their adsorption behavior in aqueous solution.…”