Abstract The paper presents the results of Cr, Co, Cu, Fe, Ni, Mn, Pb, Zn, and four radionuclides (226Ra,232Th, 137Cs, and 40K) determination in transplanted lichens after two, four, and six months of exposure. Lichens were sampled from the area of Mountain Igman in Bosnia and Herzegovina (BiH) and transplanted to two locations (Pofalići and Bjelave) in Sarajevo, the capital city of BiH. The total metals content was determined by flame atomic absorption spectrometry (FAAS). Gamma spectrometry (GS) was used for radionuclide activity determination. Content of Cr, Co, Cu, Fe, Mn, Ni, Pb an Zn in lichen after two, four, and six months of exposure ranged as follows: <LOD-0.61, <LOD-1.55, 3.85–8.08, 332.5–497.9, 19.68–31.65, 2.29–4.24, <LOD-10.30, 32.76–58.58 µg/g, respectively. Cr was not detected in exposed lichen samples. A very strong positive correlation for Cu-Cu, Cu-Fe, Cu-Pb, Cu-Zn, Ni-Ni and Fe-Fe was obtained in lichens, while a strong correlation was between Co-Zn, Co-Cu, Pb-Pb and Mn-Mn. The specific activity of 137Cs ranged from 19.95 to 56.66 Bq/kg, while for 40K ranged from 49.65 to 330.61 Bq/kg. The specific activity of 226Ra and 232Th was below the GS limit of detection.

Adsorption for uranium removal from aqueous systems has been extensively studied, due to its many advantages. However, the great costs and complexity of many sorbent preparation methods are still restricting the progress. Hence, this research aimed to introduce a novel, simple and green method for enhancing Amberlite IR-120 properties for U(VI) removal. Adsorption process parameters were evaluated by batch method and sorbent was characterized before and after uranium adsorption by FTIR, SEM and EDS analysis. The results demonstrated that sorbent was effective for U(VI) removal at pH 5, 100 mg dose with 60 mg/L of U(VI) concentration within 40 min at higher temperatures. The removal efficiency was 87.7% and process was found feasible according to thermodynamic data. Kinetic modelling showed best correlation with pseudo-second order model (r2 = 0.999) and applied isotherms could all describe investigated process suggesting a complex mechanism of U(VI) uptake. Effect of interfering ions (Pb(II), Ni(II) and Co(II)) in a concentration of 45 and 60 mg/L decreased U(VI) removal to 45%. Additionally, AAS method confirmed that used sorbent has significant affinity towards Pb(II). Desorption study revealed successful uranium recovery in up to 3 cycles of sorption/desorption. The EDS analysis revealed the uranium presence with 4.7% and FTIR analysis revealed bands characteristic for stretching vibrations of O=U=O. Proposed mechanism involved U(VI) uptake via non-covalent interactions, inter/intra-molecular hydrogen bonding and intraparticle diffusion. Techno-economic analysis showed that with used preparation method 1 g of ASP costs 0.022 $. Hence, this study offers a novel method for sorbents properties enhancements.

The issue of water contamination by heavy metal ions as highly persistent pollutants with harmful influence primarily on biological systems, even in trace levels, has become a great environmental concern globally. Therefore, there is a need for the use of highly sensitive techniques or preconcentration methods for the removal of heavy metal ions at trace levels. Thus, this research investigates a novel approach by examining the possibility of using pomegranate (Punica granatum) peel layered material for the simultaneous preconcentration of seven heavy metal ions; Cd(II), Co(II), Cr(III), Cu(II), Mn(II), Ni(II) and Pb(II) from aqueous solution and three river water samples. The quantification of the heavy metals was performed by the means of FAAS technique. The characterization of biomaterial was performed by SEM/EDS, FTIR analysis and pHpzc determination before and after the remediation process. The reusability study, as well as the influence of interfering ions (Ca, K, Mg, Na and Zn) were evaluated. The conditions of preconcentration by the column method included the optimization of solution pH (5); flow rate (1.5 mL/min), a dose of biosorbent (200 mg), type of the eluent (1 mol/L HNO3), sample volume (100 mL) and sorbent fraction (<0.25 mm). The biosorbent capacity ranged from 4.45 to 57.70 μmol/g for the investigated heavy metals. The practical relevance of this study is further extended by novel data regarding adsorbent cost analysis (17.49 $/mol). The Punica granatum sorbent represents a highly effective and economical biosorbent for the preconcentration of heavy metal ions for possible application in industrial sectors.