The recycling of spent lithium-ion batteries (LIBs) requires efficient and sustainable methods for recovering critical metals. In this study, the leaching behavior of LiCoO₂ cathode material obtained from spent LIBs was investigated in phosphoric acid, using copper powder recovered from waste LIBs as a reducing agent. Leaching experiments were conducted under various conditions (temperature, solid-to-liquid ratio, agitation rate) and compared with systems without copper. In the absence of copper, lithium and cobalt, recoveries after 30 min were approximately 77% and 23%, respectively. The addition of copper significantly enhanced leaching, achieving >96% recovery for both metals at 80 °C, with most extraction occurring within the first 30 min. Kinetic analysis using the shrinking core model indicated a mixed-control mechanism involving both surface chemical reaction and product layer diffusion. The calculated activation energies were 20.2 kJ·mol⁻¹ for lithium and 16.1 kJ·mol⁻¹ for cobalt. Solid residues were characterized by X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). XRD results revealed that the composition of the residues varied with leaching temperature: Co₃O₄ was consistently detected, whereas Cu₈(PO₃OH)₂(PO₄)₄·7H₂O appeared only when leaching was performed above 50 °C. Thermodynamic calculations supported the reductive role of copper and provided insight into possible reaction pathways. These findings confirm the effectiveness of copper-mediated leaching in phosphoric acid and demonstrate that temperature strongly influences residue phase evolution, thereby offering valuable guidance for the design of sustainable LIB recycling processes.

The soil phytomonitoring and phytostabilization potential of Syringa vulgaris and Ficus carica was evaluated regarding 16 priority polycyclic aromatic hydrocarbons (PAHs) using a chemometric approach and the calculation of bioconcentration factors (BCFs) for each individual PAH in plants’ roots from each selected location in the Bor region. PAHs in roots and the corresponding soils were analyzed using the QuEChERS (Quick, Effective, Cheap, Easy, Rugged, Safe) method with some new modifications, gas chromatography/mass spectrometry, Pearson’s correlation study, hierarchical cluster analysis, and BCFs. Several central conclusions are as follows: Each plant species developed its own specific capability for PAH management, and root concentrations ranged from not detected (for several compounds) to 5592 μg/kg (for fluorene in S. vulgaris). In some cases, especially regarding benzo(a)pyrene and chrysene, both plants had a similar tactic—the total avoidance of assimilation (probably due to their high toxicity). Both plants retained significant quantities of different PAHs in their roots (many calculated BCFs were higher than 1 or were even extremely high), which recommends them for PAH phytostabilization (especially fluorene, benzo(b)fluoranthene, and benzo(k)fluoranthene). In soil monitoring, neither of the plants are helpful because their roots do not reflect the actual situation found in soil. Finally, the analysis of the corresponding soils provided useful monitoring information.

Polycyclic aromatic hydrocarbons (PAHs) are considered as the pollutants of highest priority, and their remediation is of a global concern. The purpose of this study was to investigate the phytoremediation potential of Hedera helix (Hh) determining the content of 16 priority PAHs in its soil and root samples collected from the rural and industrial zones of the Bor's municipality (Serbia). The content of Ʃ16 PAHs in the soils was: 326.49 mg/kg at the site Borsko jezero to maximal 1937.64 mg/kg at the site Slatinsko naselje. The level of soil pollution (depending on the concentration of S16 PAHs), was high at many tested sites and it was under the significant influence of anthropogenic activities. The concentration for S16 PAHs in the samples of roots ranged from 480.71 mg/kg at the site Krivelj to 1748.32 mg/kg at the site Naselje Sunce. Interestingly, the extremely toxic benzo(a)pyrene, was not detected in the roots of Hh. Bioconcentration factors (BCFs) were applied to determine the capacity of Hh for PAH accumulation in the root, and consequently, for determination of its phytostabilization potential. In most cases, BCF values were higher at the locations from UI zone. The calculated BCFs were higher for LMW PAHs than for HMW PAHs. At the majority of the investigated locations, the tested plant species was especially successful in the root accumulation of the compounds such as acenaphthene, fluorene, anthracene, dibenzo(a,h)anthracene, and the sum of benzo(k)fluoranthene and benzo(b)fluoranthene. These findings showed that Hh can be successfully used in phytostabilization of many PAHs.

The aim of this work was to investigate the phytomonitoring potentials of Hedera helix L. from the Bors municipality concerning (atmospheric) Pyrene as a well-known hazardous substance. The results of gas chromatographic-mass spectrometric analysis of the unwashed stems and leaves showed that Pyrene concentrations obviously varied at all selected rural and urban/industrial zones (RZ and UIZ). These first signs of various sources of Pyrene in the investigated area were later supported by the results of the performed Pearson's correlation analysis, which showed that the detected Pyrene concentrations came not only from the vicinal heating and smelting plants, as the main sources of pollution in the whole region but also from the domestic heating in RZ, or forest fires, or controlled fires in the cultivated fields, and finally from the traffic in all zones. The correlation analysis also signalized that at some locations, the detected concentrations (especially in stems) came not only from the atmosphere but also from the soil. The calculated factor R confirmed the sites with the greatest atmospheric impact. Very high R values were calculated for 3 sites (two in UIZ and one in RZ) with the highest value of 1.61. Based on the obtained results, it can be concluded that the investigated stems and leaves, with the applied chemical and statistical analyses, and the calculation of R factor, can serve as a useful tool in the atmospheric Pyrene phytomonitoring.

The aim of this work was to investigate the phytomonitoring potentials of Hedera helix L. from the Bor`s municipality concerning (atmospheric) Pyrene as a well-known hazardous substance. The results of gas chromatographic-mass spectrometric analysis of the unwashed stems and leaves showed that Pyrene concentrations obviously varied at all selected rural and urban/industrial zones (RZ and UIZ). These first signs of various sources of Pyrene in the investigated area were later supported by the results of the performed Pearson’s correlation analysis, which showed that the detected Pyrene concentrations came not only from the vicinal heating and smelting plants, as the main sources of pollution in the whole region but also from the domestic heating in RZ, or forest fires, or controlled fires in the cultivated fields, and finally from the traffic in all zones. The correlation analysis also signalized that at some locations, the detected concentrations (especially in stems) came not only from the atmosphere but also from the soil. The calculated factor R confirmed the sites with the greatest atmospheric impact. Very high R values were calculated for 3 sites (two in UIZ and one in RZ) with the highest value of 1.61. Based on the obtained results, it can be concluded that the investigated stems and leaves, with the applied chemical and statistical analyses, and the calculation of R factor, can serve as a useful tool in the atmospheric Pyrene phytomonitoring.