Development of nanostructured catalysts for catalytic oxidative water purification from organic impurities, including phenolic compounds

Abstract

The purpose of this work was to create magnetic nanocatalysts that could be used for the oxidation of organic water pollutants – phenol and its derivatives – and to determine the physicochemical characteristics of the catalysts. The development of such active nanocomposite catalysts would solve the environmental problem in the Republic of Kazakhstan in the field of wastewater treatment from organic impurities, including phenols, and would also contribute to the subsequent creation of domestic production of oxygen-containing compounds, since almost the entire spectrum of oxygen-containing compounds for various industries is imported into the Republic. Nanosized magnetic composites based on Fe and Co were obtained by chemical deposition, in some cases, using polyethyleneimine and polyvinylpyrrolidone. It was shown that the interaction between nanoparticles and the polymer takes place in the case of a CoFe2O4 catalyst stabilized with polyvinylpyrrolidone or polyethyleneimine, which may indicate the efficient formation of nanocomposites. According to the IR study, for the CoFe2O4 nanocomposite stabilized with polyvinylpyrrolidone, the absorption bands at 735, 663, 649, 626 cm–1 are natural vibrations for the composite nanoparticles embedded in a polyvinylpyrrolidone matrix. The synthesized nanocomposites were tested in the oxidation of phenol with oxygen. The results demonstrate that the catalysts are promising both for the purification of industrial wastewater from phenol and for the synthesis of oxygen-containing compounds in the liquid phase under mild conditions.

Catalysts Based on Nanoscale Iron and Cobalt Immobilized on Polymers for Catalytic Oxidation of Aromatic Hydrocarbons: Synthesis, Physico-Chemical Studies, and Tests of Catalytic Activity

“…The X-ray diffraction pattern of the synthesized Fe 3 O 4 (Figure 2a) proves the crystal structure of magnetite, and the peaks in the diffraction pattern at 35 • /43 • /57 • /63 • /74 • correspond to the lattice planes (311), (400), ( 422 Also, a detailed description of the methodology for obtaining catalysts and equipment for physical and chemical research is described in our previous articles [16,45].…”

“…The wavelength can vary in the range from 190 to 1100 nm. Also, a detailed description of the methodology for obtaining catalysts and equipment for physical and chemical research is described in our previous articles [16,45].…”

“…To stabilize magnetic nanoparticles, their surface is coated with materials of both organic and inorganic nature. Such coatings solve a dual problem: firstly, they prevent the aggregation of nanoparticles and the oxidation of magnetite (both problems are, for example, fundamental in the transport of nanomaterials); secondly, they allow for modification of the surface of nanoparticles with various specific ligands for the intended use [11][12][13][14][15][16][17][18][19][20][21][22][23][24]. Currently, a promising direction is the synthesis and application of magnetic nanoparticles stabilized by modifiers: polymers of natural and artificial origin.…”

Catalysts Based on Iron Oxides for Wastewater Purification from Phenolic Compounds: Synthesis, Physicochemical Analysis, Determination of Catalytic Activity

“…Therefore, it is quite difficult to ensure highly effective purification from phenol compounds in most enterprises. The search for catalysts for the oxidation of organic substances in aqueous solutions is an urgent task [40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55].…”

“…Magnetite-based nanomaterials are widely used as part of composite systems in medicine, biotechnology and engineering. In particular, catalysts based on nanosized magnetite have fast adsorption-desorption kinetics and high chemical activity [32][33][34][35]37,38,[47][48][49][50][51][52][56][57][58][59][60][61]. Due to its excellent physicochemical properties, iron oxide (Fe 3 O 4 ) has attracted much attention in recent years.…”