abstract
- This paper deals with the preparation of magnetic adsorbents from natural clays for the adsorption of Ni(II) from aqueous matrices. The phase composition and structure parameters of natural clays and their modified forms, as well as their application as adsorbing agents for the purification of drinking water and their sources were studied. In the study, natural clays from the Zhetisay deposit of Kazakhstan were used to obtain magnetic composites by chemical coprecipitation and applied as effective adsorbents to remove Ni(II) from water. The formation of sorbents by magnetic nanoparticles is an urgent task of our time. This is due to the needs of various branches of science and technology in magnetically controlled sorbents. The advantage of such sorbents in comparison with natural sorbents is the ability to control them using a magnetic field. Sorbents with magnetic properties are used for contact cleaning of substances, which greatly simplifies the sorption process and the completeness of the sorbent processing. The use of such materials makes it possible to replace the mechanical separation stage, which is one of the labor-intensive stages of this process. Magnetic pillared clays were obtained by intercalation of iron and manganese cations in the region between the clay silicate layers, upon hydrolysis of a solution of Fe2(SO4)3·9H2O and MnCl2·4H2O with NaOH. The intercalated clay is then dried and calcined at 400°C for 3 h. The basic physical and chemical properties were stu died by XRD, elemental analysis, FTIR and atomic emission spectral analysis (AES). The obtained magnetic pillared clays (MnFe2O4/Zhetisay) showed better characteristics than natural clays. The results of adsorption revealed that the optimal adsorption conditions were observed at pH 6.