In this study, the possibilities of selective sorption of neodymium and praseodymium ions from a mixture of their solution using interpolymer systems composed of two industrial sorbents, cation exchangers KU-2-8 (Na⁺) and AB-17-8 (Cl⁻), at different molar ratios were investigated. The processes of sorption and desorption were carried out in two modes: dynamic (with active stirring) and static (without stirring the working solution from which REEs were extracted). According to the obtained results, sorption in the dynamic mode in the ratios of 4:2 and 3:3 does not lead to any selectivity. However, a high degree of extraction was noted for both ions: Pr³⁺ = 99.36%, Nd³⁺ = 95.67% for the 4:2 system and Pr³⁺ = 81.33%, Nd³⁺ = 79% for the 3:3 system. In the static mode, the degree of extraction of both metals was significantly lower: for the 4:2 system Pr³⁺ = 19.33%, Nd³⁺ = 24%, but greater selectivity with respect to neodymium was observed. With a ratio of 4:2, neodymium was sorbed better than praseodymium by 24.16%, and in the 3:3 system by 39.83%. When desorption from the cationite was carried out with nitric acid, a similar tendency was preserved. Thus, it was shown that interpolymer systems can be used in industry by varying the conditions of sorption and desorption for the successful extraction of neodymium and praseodymium from industrial solutions.

This paper presents a study of the kinetics of neodymium and praseodymium ions sorption using interpolymer systems based on KU-2-8 and AB-17-8 in salt forms. Sorption of target ions was carried out in a dynamic mode (with constant stirring) in interpolymer systems in molar ratios of 4:2 and 3:3 (cation exchanger to anion exchanger). Aliquots were collected during certain time intervals, then widely known kinetic models of sorption were used to construct linear graphs. According to the obtained results, the best model for describing sorption was pseudo-first order (the highest value for the 4:2 system = 0.97885 and 0.98112; for the 3:3 system = 0.9647 and 0.98779). Such results are important for understanding the mechanisms of the sorption process and establishing the limiting factor that can slow down this process. The kinetic model of pseudo-first order may indicate the need to improve the washing out of counterions from the polyelectrolyte matrix for their high ionization and accessibility of functional groups for metal ions. This assumption can be used in the future to optimize industrial schemes of ion-exchange sorption of REE.

The current digital transformation of education is accompanied by the active integration of artificial intelligence (AI) tools into the educational process. In science education, this creates new questions and conditions for developing critical thinking in students and poses a challenge for researchers and practicing educators to analyze the effectiveness and risks of AI technologies. This paper presents a systematic literature review, conducted according to PRISMA standards, to analyze the impact of AI tools on the development of critical thinking in science education. The search was conducted in the Taylor & Francis, IEEE Xplore, Wiley Online Library, and Google Scholar databases for the period 2022–2025. Of the 546 identified publications, 12 studies were selected after applying the inclusion and exclusion criteria. The analysis revealed that the use of generative chatbots, machine learning, written work analytics, and AI-STEM projects in general contributes to the development of critical thinking, argumentation, reflection, and academic motivation. Risks identified include unreliable data, dependence on digital tools, decreased teacher creativity, and ethical and privacy issues. The review emphasizes the need for more rigorous research using standardized tools to assess critical thinking and expanding the scope of the study to include various disciplines within the natural sciences.

In this study, the possibilities of selective sorption of neodymium and praseodymium ions from a mixture of their solution were studied. For this purpose, based on the obtained results on the dynamics of sorption of each ion separately by industrial hydrogels KU-2-8 (Na+): AV-17-8 (Cl-), interpolymer systems with different molar ratios of cation exchanger and anion exchanger, namely 4:2 and 3:3, respectively, were selected. The choice of these ratios was based on the detection of increased sorption of praseodymium ions from a model solution compared to neodymium ions. The sorption (48 h.) and desorption (72 h.) processes were carried out in two modes: dynamic (with active mixing, speed range 80-150 rpm) and static (without mixing the working solution from which REE were extracted), at room temperature (close to 25° С). According to the obtained results, sorption in the dynamic mode in the ratios of 4:2 and 3:3 does not lead to any selectivity (praseodymium ions were sorbed better than neodymium ions by 3.93% and 2.96% for each ratio). However, a high degree of extraction was noted for both ions: Pr3+ = 99.36%, Nd3+ = 95.67% for the 4:2 system and Pr3+ = 81.33%, Nd3+ =79% for the 3:3 system. In the static mode, the degree of extraction of both metals was significantly lower: for the 4:2 system Pr3+ = 19.33%, Nd3+ = 24%.But, despite this, in the static mode, greater selectivity was observed with respect to one of the metals, namely neodymium. Thus, with a ratio of 4:2, neodymium was sorbed better than praseodymium by 24.16%, and in the 3:3 system by 39.83%. When desorption was carried out from the cationite, a similar picture was also preserved. From here it becomes clear the relevance and necessity of further study of the issue of choosing a technological mode for the sorption of REE from industrial solutions, as well as the creation and selection of similar interpolymer systems that can provide sufficient selectivity in relation to one of the target ions in several extraction cycles.

This research aimed to study the effect of remote interaction and mutual activation between salt forms of AB-17-8(Cl-) and KU-2-8(Na+) ion exchange resins on the sorption of neodymium ions. The concentration of neodymium ions was determined using a spectrophotometer based on the interaction with the colored arsenazo (III) reagent. The degree of extraction of neodymium ions during sorption and the degree of extraction of this metal during desorption from the polymer matrix was calculated. The influence of the choice of sorption mode on the efficiency of neodymium extraction is studied: dynamic (with mixing of the solution from which the metal was extracted) and static (without mixing). Based on the obtained dynamics of processes, it is established that when mixing the solution (the range of mixing speed is 40-80 rpm) the equilibrium between sorption and desorption of the metal is established after 6 hours of interaction. Also, in the dynamic mode, the target metal was sorbed much better than in the static mode, affecting the amount of metal ions obtained during desorption. It was found that the maximum degree of neodymium ion sorption in the interpolymer system is observed at a 5:1 hydrogel ratio and 48 hours of remote interaction without mixing. It is 42.8 mg/l of the residual concentration. In the dynamic mode, the maximum sorption is observed for the initial cationite, with a residual concentration of 8.28 mg/l. When calculated per 1 mol of cationite, the effect of mutual activation of hydrogels is visible, which is proved by the tendency to increase the degree of neodymium sorption from the ratio of 6:0 (the initial cationite) to 1:5. A significant increase in the sorption of neodymium ions is observed in various molar ratios of ionites. These results indicate the appearance of ionized structures that form conformations that provide optimal conditions for the sorption of neodymium ions from an aqueous solution of its salt, which can serve practical purposes for its selective extraction from industrial mixtures. The necessity of metal extraction by hydrogels in dynamic mode is established for faster operation of industrial plants and more complete metal binding by polymer matrices.