Amino-functionalized Nano-size Composite Materials for Dispersive Solid-Phase Extraction of Phosphate in Water Samples

Abstract

An efficient analytical method for the preconcentration and determination of phosphate in water samples at trace levels was proposed. The method was based on sample enrichment using dispersive solid-phase extraction (dSPE) with tetraethylenepentamine (TEPA)-functionalized nano-size composite materials (TEPA-NCMs) as sorbents, which were fully characterized. Various parameters affecting the extraction efficiency were systematically investigated. After extraction, the post-adsorbed TEPA-NCMs were eluted by a NaOH solution for desorption of the phosphate. The resulting eluate containing phosphate was determined by a spectrophotometric method. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.29 and 0.96 μg L -1 , respectively. The relative standard deviations (RSDs) were lower than 8.0% with average recoveries ranging from 91 to 118%. The present method was successfully applied to the determination of phosphate at trace levels in real water samples, and it was confirmed that the TEPA-NCMs are highly effective dSPE materials.

Adsorption of phosphate onto amine functionalized nano-sized magnetic polymer adsorbents: mechanism and magnetic effects

“…Since the polymer shell was diamagnetism, it was reasonable that the ratio of paramagnetic composition reduced, which led to lower saturation moments than that of the bare Table 2. 16,19 With an increase of pH, the TEPA-Fe 3 O 4 -NMPs surface carried positive charge, and thus would more signicantly attract the negatively charged monovalent H 2 PO 4 À ions in solution, which indicated that the physicochemical adsorption due to electrostatic attraction was the predominant process of phosphate removal, as described by eqn (7). On the contrary, the concentration of the N element on their surfaces increased from 4.53% to 8.53%, with the usage amount of Fe 3 O 4 increasing from 0.5 g to 2 g, even though the total contents of the nitrogen decreased as founded in elemental analysis.…”

“…Although there have been many signicant developments in the synthesis of magnetic nanoparticles, maintaining the stability of these particles for a long time without agglomeration or precipitation is an important issue. 16,17 With more and more strictly environmental regulations on the discharge of phosphorus and rising demands for clean water with extremely low levels of phosphorus, functionalized-magnetic nanoparticles, with enhanced adsorption rate, capacity, and selectivity, have gradually attracted researchers' great interest to be used as adsorbents for phosphorus removal. Functional polymers coating on the magnetic core enhanced the stability of nanodispersions by preventing their aggregation, moreover, the absorption properties can be tailored by suitable functional groups.…”

“…Recently, nano magnetic polymers (NMPs) have been intensively studied, not only for scientic interest, but also for technological applications, such as magnetic uids, 1 catalysis, 2 biotechnology/biomedicine, 3,4 contrast agents in magnetic resonance imaging (MRI), 5,6 data storage, 7 and environmental remediation. [8][9][10][11][12][13][14][15][16] However, bare magnetite nanoparticles are quite susceptible to air oxidation and are easily aggregated in aqueous systems. Although there have been many signicant developments in the synthesis of magnetic nanoparticles, maintaining the stability of these particles for a long time without agglomeration or precipitation is an important issue.…”

Controlled synthesis of 2,4,6-trichlorophenol-imprinted amino-functionalized nano-Fe3O4-polymer magnetic composite for highly selective adsorption

“…The N1s high-resolution scan of nFe 3 O 4 @EDAMIP could be deconvoluted into two individual peaks at binding energies of 398.6 eV and 396.5 eV (Fig. 5b), which were assigned to the N atoms in C NH 2 and C NH C groups [26], respectively. A new peak at 399.8 eV was observed after 2,4,6-TCP adsorption, which could be attributed to the hydrogen bonding of ph O H· · ·NH 2 or N H· · ·O ph [27].…”

The Removal of Phosphate and Arsenate from Aqueous Solution Using Silica Based Materials

“…The maximum percentage of extraction was achieved using bark ash of C. auriculata at a pH 10 in the presence of interfering cations (Mg 2+ , Cu 2+ , Zn 2+ , Fe 2+ and Ni 2+ ). Nano-size composite materials functionalized with amino groups were also used for phosphate extraction by Shen and co-workers [9]. The removal of arsenic species in water using the macrocycle known as calix [4] pyrrole has been discussed by Danil de Namor and co-workers [10].…”