4-amine-2-mercaptopyrimidine modified silica gel applied in Cd(II) and Pb(II) extraction from an aqueous medium

Abstract

This paper discusses silica surface modification by a process involving a two-step reaction: anchoring of a silylating agent, followed by an attachment of a 4-amino-2-mercaptopyrimidine molecule. The modified material (Si-BP) was successfully characterized by the FTIR spectra, which revealed amine absorption bands, and through 13 C and 29 Si NMR spectra, which confirm the proposed structure of the modified silica (Si-BP). Si-BP was used to extract cadmium and lead from an aqueous medium at 298 K. The Si-BP kinetics towards metal ions was very fast, i.e., about 10 minutes, although extraction was significantly impaired at pH 3. The series of adsorption isotherms were adjusted to a modified Langmuir equation and the maximum extraction capacity was 0.193 and 0.387 mmol g -1 for Cd(II) and Pb(II), respectively. An analysis of the Ø values lead to the inference that the resulting metal ligand complex was type 1:1.

Sorption and Desorption Studies of Pb(II) and Ni(II) from Aqueous Solutions by a New Composite Based on Alginate and Magadiite Materials

“…In addition, Table 3 shows a comparison of the maximum sorption capacities of the materials reported in the literature; e.g., CAM-D2EHPA has a greater nickel sorption capacity compared to the impregnated solids studied by Gonzalez et al [ 48 ] (XAD-2-Cyanex 272). The removal of lead is also comparable with the results obtained by Pereira et al [ 17 ], Bhattacharyya et al [ 47 ], Asuquo et al [ 49 ], and Puppa et al [ 50 ]. CAM-D2EHPA has two important advantages: (i) it is easy to manufacture, which is interesting for industrial scale production, and (ii) it has a high sorption uptake.…”

“…Sorption is considered as the most suitable method for removing heavy metals because of its promising advantages [ 12 , 13 , 14 , 15 ]: (i) high efficiency uptake for binding metal ions at low concentrations; (ii) energy saving, and iii) easy recycling of the loaded sorbent. Nevertheless, a good design of the material is required to achieve high performances [ 17 , 18 , 19 ].…”

Mucor pusillus immobilized Amberlite XAD-4 biocomposites for preconcentration of heavy metal ions by solid-phase extraction method

“…Various methods have been discussed and applied for the preconcentration of metal ions, including liquid-liquid extraction (LLE) (Anthemidis and Ioannou 2009), coprecipitation (Saracoglu et al 2012), cloud point extraction (CPE) (Hongbo et al 2013), and solid-phase extraction (SPE) (Sahmetlioglu et al 2014;Baytak and Arslan 2015;Baytak and Kasumov 2017),which are used to solve these problems of trace metal determinations. SPE has been a most promising technique because of its simplicity, use of small volume of solvent, and ability to obtain a high preconcentration factor and high speed (Baytak and Arslan 2015;Baytak and Kasumov 2017;Krawczyk et al 2014) .Various adsorbents have been investigated in SPE such as multi-walled carbon nanotubes (Li et al 2013;Alothman et al 2012;Wang et al 2011), magnetic nanoparticles (Asgharinezhad et al 2014;Khajeh 2009), solid sulfur (Parham et al 2009), cotton (Faraji et al 2009), modified porous materials (Matbouie et al 2013;Taghizadeh et al 2013;Pereira et al 2010), and Amberlite XAD resins for preconcentration and separation of trace metal ions from various media (Baytak and Turker 2005a).…”

Octa-<i>O</i>-Methoxy Resorcin [4] Arene Amberlite XAD-4 Polymeric Chelating Resin for Solid Phase Extraction, Preconcentration, Separation and Trace Determination of Ni(II), Cu(II), Zn(II) and Cd(II) Ions

“…Various SPE materials which have been used for the preconcentration of trace metal ions as their chelates include, activated silica gel [40,41], carbon [42][43][44][45], polyurethane foam [46] microcrystalline naphthalene [47], C 18 cartridges [48], Chelex-100 [49], Alumina [50], functionalized polyurethane foam [51], modified silica [52,53], sulfur powder [54] and Amberlite XAD resins [55][56][57][58][59][60][61]. Amberlite XAD (styrene-divinyl benzene copolymer) resins, as the copolymer backbone for the immobilization of chelating ligands, have some physical superiority, such as porosity, uniform pore size distribution, high surface area, and chemical stability toward acids, bases, and oxidizing agents, as compared to other resins [62][63][64][65].…”