A magnetic polymer material based on natural polymers—humic acids and magnetite, pre-configured for the sorption of a metal ion—was obtained. The magnetic polymer material was obtained via the interaction of a natural polymer, magnetite nanoparticles and sorbed metal ions that were used as a template. Moreover, the formation of a pre-polymerization complex was followed by copolycondensation with an amine in the presence of a crosslinking agent and further removal of metal ions from the crosslinked copolymer. The physicochemical properties of the resulting materials were determined using various physical methods. The composition of the resulting magnetic polymer materials was characterized by elemental analysis using an Elementar Unicube elemental analyzer. It was found that the carbon content increases by 8.28% and nitrogen by 0.42% for the polymer material Fe₃O₄:HA:T:AA; for the polymer material Fe₃O₄:HA:AA, the carbon content increases by 14.61% and nitrogen by 3.01%. Based on the IR spectra data, it is clear that magnetic polymer materials have much in common before hydrolysis (Fe₃O₄:HA:T:AA) and after hydrolysis (Fe₃O₄:HA:AA). The structure of the resulting polymer materials was studied using electron microscopy. Micrographs show the presence of pores in magnetic polymer materials after acid hydrolysis, indicating the formation of imprints. The results of the study of the sorption properties of magnetic polymer materials showed that after acid hydrolysis, the sorption capacity of a customized magnetic polymer material increases two times and it can act as a magnetic sorption material.

A composite based on amino-containing humic acid with the immobilization of multi-walled carbon nanotubes preliminarily tuned to a copper ion has been obtained. The synthesis of a composite pre-tuned for sorption by the local arrangement of macromolecular regions was obtained by introducing multi-walled carbon nanotubes and a molecular template into the composition of humic acid, followed by copolycondensation with acrylic acid amide and formaldehyde. The template was removed from the polymer network by acid hydrolysis. As a result of this tuning, the macromolecules of the composite “remember” conformations that are favorable for sorption, i.e., adsorption centers are formed in the polymer network of the composite, capable of repeated, highly specific interaction with the template and the highly selective extraction of target molecules from the solution. The reaction was controlled by the added amine and by the content of oxygen-containing groups. The structure and composition of the resulting composite were proven by physicochemical methods. A study of the sorption properties of the composite showed that after acid hydrolysis, the capacity increased sharply compared to a similar composite without tuning and a composite before hydrolysis. The resulting composite can be used as a selective sorbent in the process of wastewater treatment.

Composite materials based on amino-containing humic acids with the introduction of carbon nanotubes, capable of molecular recognition and selective binding

A nanocomposite material based on humic acid and functionalized multiwalled carbon nanotubes was obtained using ultrasonic treatment. The composition and p

In this work, molecularly imprinted polymers with zinc imprints and their comparison polymers without imprints were synthesized. A comparative characterization of the physical parameters of the synthesized zinc-imprinted (ZnIP) and non-imprinted (NIP) polymers was carried out using the methods of elemental analysis, conductometry, scanning electron microscopy, and IR-Fourier spectroscopy. The ability of the resulting polymers to molecularly recognize zinc was evaluated. Based on experimental data on static adsorption, the adsorption capacity of ZnIP and NIP was determined using an atomic emission spectrometer. It was found that ZnIP is characterized by better physical parameters and a higher ability for molecular recognition of zinc compared to NIP. ZnIP with zinc imprints were found to have better sorption capacity for zinc than their reference polymers. The sorption of zinc by molecular imprinted ZnIP is mainly due to the complex formation and pores of the initial carbon product. The synthesized ZnIP have increased porosity. The presence of pores with a diameter <50 nm in ZnIP is associated with voids formed after acid hydrolysis, which is clearly visible in images recorded by scanning electron microscopy. Thus, the possibility of using ZnIP as a selective sorbent has been established.