Adsorption of Designed Pyrimidine Derivative Ligands on an Activated Carbon for the Removal of Cu(II) Ions from Aqueous Solution

Abstract

The adsorption of five Nalpha-substituted amino acids with a 5-nitroso-6-oxo pyrimidine as substituent on a commercial activated carbon (AC) has been studied in aqueous solution at several pH values. The adsorption processes of these organic compounds have been analyzed on the basis of the electrolytic behavior of the adsorbates. In all cases, the adsorption process is highly irreversible due to strong pi-pi interactions between the arene centers of the AC and the pyrimidine residue of the adsorbates. This interaction is consistent with XPS data and HOMO-LUMO theoretical calculations. The adsorption of these organic compounds provides a new route for the functionalization of the AC surface with carboxyl groups. In addition, the adsorption capacity of the AC/organic compound systems for Cu(II) ions in aqueous solution has been studied at different pH values. These systems show an increase of the adsorption capacity for Cu(II) compared to the AC, which is related to the AC functionalization with carboxyl groups due to the adsorbed organic compounds.

New hybrid materials based on the grafting of Pd(ii)-amino complexes on the graphitic surface of AC: preparation, structures and catalytic properties

“…A commercial activated carbon, AC, Merck K24504014 (Merck hereinafter), previously characterized, 11,13,14 was used as-received. All solvents and other chemicals were of analytical grade and used as received.…”

“…[11][12][13] Moreover if the majority of the Ar-S-F molecules are adsorbed into open pores (meso-and macropores) the strong π-π interactions give rise to stable AC/Ar-S-F hybrid materials. In these hybrids the functional groups conjugated with the pyrimidine (plane) residue are blocked (due to the plane to plane interaction) whilst, should the character of S-F residues are non-aromatic, the properties of F (free) functions are efficiently transferred to the AC surface.…”

“…14 Thus, once the Ar-S-F molecules are adsorbed into open pores the subsequent adsorption of metal ions by the hybrid materials AC/Ar-S-F is mainly controlled via complexation of the metal ion by the F function (Scheme 1). 12,13,[15][16][17] This provides a suitable strategy to prepare solid catalysts based on the catalytic properties of metal-ion complexes supported on the graphene surface of the AC. This method catalyst preparation has two important advantages: i) it allows the exhaustive control of the amount of active sites on the surface of the hybrid material and ii) the textural and chemical functions of the starting AC remain unaltered in the hybrid due to the soft conditions of preparation.…”

Adsorption of Metal Ions on an Activated Carbon/L‐Lysine Derivative Hybrid Compound

“…[9][10][11] These molecular receptors contain a planar pyrimidine moiety (Ar), which acts as an anchor to attach the receptors onto the arene centres of the activated carbon. This pyrimidine fragment is connected through a polymethylene aliphatic arm (S) to a Lewis base function (F), which acts as an active site for complexation of the metal centres (Scheme 1).…”

Removal of Dimethyl Sulfide from Aqueous Solution Using Cost-Effective Modified Chicken Manure Biochar Produced from Slow Pyrolysis

“…Although pretreatments or modification of carbon materials such as BCs increase cost, they are necessary steps for improving the selective adsorption of pollutants and for increasing adsorption capacity. Several methods (e.g., acid and alkali modification, oxidation, and chemical grafting) have been used for the pretreatment or modification of BC in order to improve the adsorption capacity [29][30][31]. Generally, these techniques modify the BC's interfacial regions by increasing its specific surface area, porous structure or chemical reactivity obtained through the formation of surface functional groups that can chemically bond or interact (chelate) with the DMS.…”