Novel magnetic polymer/bentonite composite: Characterization and application for Re(VII) and W(VI) adsorption

Abstract

A novel magnetic polymer/bentonite composite was prepared by suspension copolymerization of glycidyl methacrylate and ethylene glycol dimethacrylate in the presence of magnetic bentonite (MB-PGME) and functionalized with ethylene diamine and hexamethylene diamine (MB-PGME-ED and MB-PGME-HD). The obtained samples were characterized in terms of structure as well as thermal, magnetic and morphological properties. The sorption of rhenium (Re) and tungsten (W) from aqueous solution onto MB-PGME-ED and MB-PGME-HD was investigated considering their contact time and different initial ion concentration, giving possibility for usage of these composites as commercial sorbents. The sorption system follows the pseudo-second order and intraparticle diffusion kinetic models. The results indicated a better fit with the Freundlich isotherm model.

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

“…Additionally, the broad peak at 2 θ = 10–30° indicated the existence of an amorphous polymer coating layer on the surface of iron oxide nanoparticles. A similar observation was reported for magnetic polymer-bentonite composite [ 19 ].…”

“…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 ].…”

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

“…Then, the degradation of pGMEen/Au took place in two stages. The first stage, for a copolymer with immobilized Au, took place between 210 • C and 340 • C and the second one was in the range between 340 and 450 • C. The main degradation mechanism of pGME-en/Au was depolymerization into oligomers and monomers, initiated by the cleavage of weak linkages, ester decomposition and the elimination of the amine groups that simultaneously occur [27,36]. Also, the T i value of PGME-en/Au was approximately 20 • C higher than the T i value of pGME-en, suggesting a slight increase in thermal stability.…”

“…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].…”