Preparation of new ion-selective cross-linked poly(vinylimidazole-co-ethylene glycol dimethacrylate) using a double-imprinting process for the preconcentration of Pb2+ ions

Abstract

A new ion-selective cross-linked poly(vinylimidazole-co-ethylene glycol dimethacrylate) prepared via a double-imprinting process was developed for the recognition and preconcentration of Pb(2+) from water samples. The sorbent was characterized by FT-IR, SEM, TGA and textural data. The maximum dynamic sorption capacity of Pb(2+) was 42.04 mg Pb(2+) g(-1) of the double-imprinted polymer. The sorption kinetics data were described by a pseudo-second-order model. The double-imprinted polymer exhibited a higher sorption efficiency of Pb(2+) than the blank polymer (non-imprinted polymer). The preconcentration procedure involved the loading of a Pb(2+) solution at pH 7.25 through 40.0 mg of the double-imprinted polymer packed in a mini-column at 5.0 mL min(-1). The selective efficiency of proposed method for the Pb(2+) preconcentration was assured by competitive sorption using different proportions of Pb(2+)/cations and Pb(2+)/anions. An analytical curve was obtained in the range 0.0-300.0 μg L(-1) (r=0.999) and a limit of detection of 2.46 μg L(-1) was obtained. The preconcentration factor was found to be 21, the consumptive index 0.95 mL and the concentration efficiency 5.25 min(-1). The preconcentration method was successfully applied to the Pb(2+) ions determination in different kinds of water samples with high recovery values (91.3-108.9%).

Study on the performance of micro-flow injection preconcentration method on-line coupled to thermospray flame furnace AAS using MWCNTs wrapped with polyvinylpyridine nanocomposites as adsorbent

“…The lower surface area of the nanocomposite resulted from the low pore volume, which can be explained by the penetration of MWCNTs into the polyvinylpyridine network to occupy the pores of the polymer. On the other hand, the textural data of polyvinylpyridine are similar to those of other polymers synthesized by bulk methods, 39 and the particles have irregular shapes with rough surfaces.…”

Solid Phase Extraction to On-Line Preconcentrate Trace Cadmium Using Chemically Modified Nano-Carbon Black with 3-Mercaptopropyltrimethoxysilane

“…This parameter was determined as the ratio between the slopes calculated for the Cd 2+ preconcentration using 3-MPTMS-grafted CB and the Cd 2+ direct aspiration into the FAAS (without preconcentration). 46 The LOD and limit of quantification (LOQ), calculated according to the International Union of Pure and Applied Chemistry (IUPAC) reccomendation as three and ten times the standard deviation for the blank solution (n = 10) were found to be 0.20 and 0.66 µg L −1 , respectively. 47 The values of concentration efficiency (CE), consumptive index (CI) and sample throughput were determined as described in the literature and were found to be 7.35 min −1 , 0.54 mL and 12 h −1 , respectively.…”

Synthesis and characterization of polymer microspheres and its application for phenol adsorption

“…The peaks at 1,151 and 1,251 cm −1 and the peak with high intensity at 1,726 cm −1 can be referred to the C−O stretching and the C=O vibration of the ester group of EGDMA, respectively. The C=O vibration of the ester group of EGDMA was noted at 1,720, 1,738 and 1,721 cm −1 by Kara et al in 2004 [32], Segatelli et al in 2010 [36], and Tarley et al in 2015 [37], respectively. The characteristic peaks of imidazole ring in the polymer microspheres appear at 1643 cm −1 (stretching of C=C and C=N), 1,458cm −1 (stretching of C−C and C−N), 1,390 cm −1 (the C−N stretching modes for the ring), and 954 cm −1 (in-plane ring C−H bending) [32].…”

“…In our previous studies, we reported the adsorption capacity of the poly(ethylene glycol dimethacrylate-n-vinyl imidazole) [poly(EGDMA-VIM)] beads for Cr(VI) [31], Hg(II), Cd(II), and Cu(II) [32] as well as its immobilization of tyrosinase [33], yeast invertase [34], and α-amylase [35] on Cu 2+ chelated [poly(EGDMA-VIM)] beads. Additionally, the poly(ethylene glycol dimethacrylate-co-vinylimidazole) was used for removal of Cd 2+ [36], and Pb 2+ [37] as well as the solid phase extraction of selected non-steroidal anti-inflammatory drugs [38] and purification and isolation of phenolic acids [39]. Furthermore, PEGMA-VI microspheres were used as an adsorbent for removal of Cu(II) [40], Cr(VI), and Ni(II) [41].…”