Recovery of Vanadium (V) Oxyanions by a Magnetic Macroporous Copolymer Nanocomposite Sorbent

Abstract

An amino-functionalized magnetic macroporous copolymer of glycidyl methacrylate (GM) and ethylene glycol (E) dimethacrylate (m-poly(GME)-deta) was synthesized, fully characterized, and used to investigate the adsorption of vanadium (V) oxyanions from aqueous solutions (Ci = 0.5 mM) in a batch system at room temperature (298 K). Pseudo-first-order (PFO), pseudo-second-order (PSO), Elovich, and intra-particle diffusion (IPD) models were used to analyze the kinetic data. The study showed that sorption is rapid, i.e., the sorption half-time is approximately one minute. Initially, the sorption process primarily involved surface sorbent particles, and it was best described by the PSO model. However, after saturation of the surface active sites is attained, the sorption rate decreases significantly because of limitations of the diffusion rate, which is then primarily controlled by the IPD process. The sorption process is favorable in the pH range of 3–6 due to the strong electrostatic interactions between the absorption centers of copolymer and vanadium (V) oxyanions. In the stated pH range, deta absorption centers with two and three protonated N atoms are in equilibrium as studied by quantum chemical modeling. Among V(V) species present in diluted aqueous media, the adsorption of H2VO4− ions dominates.

Speciation of Hexavalent Chromium in Aqueous Solutions Using a Magnetic Silica-Coated Amino-Modified Glycidyl Methacrylate Polymer Nanocomposite

“…The magnetic polymer sample functionalized with diethylenetriamine (Fe 3 O 4 @APTMS/PGME-deta) was porous with a pore diameter corresponding to half of the pore volume of 286 nm and a specific pore area value of 37 m 2 /g, as determined by mercury porosimetry [ 21 ]. The sample Fe 3 O 4 @APTMS/PGME-deta was also fully characterized using SEM, TEM, ATR-FTIR, XRD, and SQUID magnetometry.…”

“…Our previous works demonstrated that calculating the coordination bond energy for the chemisorption of metal ions on the polymer gives excellent agreement with the experimentally determined maximum sorption capacities [ 27 , 67 ]. Quantum chemical modeling of physisorption and calculation of the energy of non-covalent binding proved to help explain the binding mechanism of oxyanions to the polymer and the affinity of individual oxyanions for the polymer [ 21 ].…”

“…The nanosized magnetic heavy metal sorbents based on inorganic compounds or polymers attracted increasing attention in recent years [ 16 , 17 , 18 ]. Disadvantages of magnetic nanoparticles such as self-aggregation and oxidation in the air can be overcome by incorporation of non-leachable magnetite nanoparticles in the copolymer matrix in situ and surface coating with silanization agents such as alkoxysilanes and reagents with non-hydrolyzable amino groups [ 19 , 20 , 21 ]. Among the various organotrialkoxysilane molecules for the modification of silica surfaces, (3-aminopropyl)trimethoxysilane (APTMS) and (3-aminopropyl)triethoxysilane (APTES) were widely explored by many researchers [ 20 , 21 , 22 , 23 ].…”

“…Disadvantages of magnetic nanoparticles such as self-aggregation and oxidation in the air can be overcome by incorporation of non-leachable magnetite nanoparticles in the copolymer matrix in situ and surface coating with silanization agents such as alkoxysilanes and reagents with non-hydrolyzable amino groups [ 19 , 20 , 21 ]. Among the various organotrialkoxysilane molecules for the modification of silica surfaces, (3-aminopropyl)trimethoxysilane (APTMS) and (3-aminopropyl)triethoxysilane (APTES) were widely explored by many researchers [ 20 , 21 , 22 , 23 ]. The primary advantage of magnetic nanocomposites is that they can be easily removed using a simple magnet after sorption [ 16 ].…”

Fast Gold Recovery from Aqueous Solutions and Assessment of Antimicrobial Activities of Novel Gold Composite

“…As a result of extensive research, Jovanović et al developed GMA-based polymeric sorbents with adjustable porosity parameters by varying the type and the amount of aliphatic alcohol and crosslinking monomer in the reaction mixture [23]. A plethora of amino-functionalized porous polymers and composites were used as heavy and precious metal sorbents, with the possibility to coordinate gold and platinum metals or bind them as chloro complexes as basic ion exchangers, depending on pH [24][25][26][27][28][29].…”