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Waste Supermaterials: Engineered Multifunctional Composites for Dual Water- Waste Solutions
No full textPreparation and Characterization of Hydroxyapatite-Modified Natural Zeolite: Application as Adsorbent for Ni2+ and Cr3+ Ion Removal from Aqueous Solutions
No full textNatural zeolites (NatZ) are widely available, porous, crystalline aluminosilicate
minerals that are commonly used as cost-effective adsorbents in water treatment processes.
Despite their efficiency in removing various heavy metal ions from wastewater, NatZ show
relatively low affinity toward Ni2+ and Cr3+ ions. This study aimed to develop composite
adsorbents based on NatZ and hydroxyapatite using two methods, hydrothermal and
mechanochemical, and their adsorption properties for the removal of Ni2+ and Cr3+ ions
from aqueous solutions were investigated. X-ray powder diffraction and scanning electron
microscopy analyses confirmed that under hydrothermal conditions, needle-like hydroxyapatite
crystals were formed on the surface of NatZ, while the zeolite structure remained
unchanged. Compared to the mechanochemically prepared sample, this adsorbent showed
higher efficiency, binding 6.91 mg Ni2+/g and 16.95 mg Cr3+/g. Adsorption kinetics of the
tested cations in both cases can be described by a pseudo-second-order model (R2 is higher
than 0.95 for all adsorbents). It is concluded that the presence of hydroxyapatite on the
zeolite surface significantly improves the adsorption performance of NatZ, demonstrating
its potential for the removal of heavy metal ions in wastewater treatment
Potential effects of environmental microplastics on phytoremediation of Cu, Mn And Sr from serbian urban soils
No full textMicroplastics (MPs) are omnipresent contaminants, becoming a global environmental and ecological
concern. MPs and potentially toxic elements (PTEs) often coexist in soil. However, the impacts of MPs on
soil-plant systems and phytoremediation of PTEs are still poorly acknowledged. This field study investigated MPs prevalence in four Serbian cities and evaluated potential impacts on the uptake of PTEs (Cu, Mn, and Sr) by Capsella bursa-pastoris (L.) Medik. MPs isolation from soil samples was conducted using the optimized density separation method. Total (aqua regia) and phytoavailable (EDTA) PTEs fractions in soils were analyzed alongside the concentrations in plant roots and shoots. Soils from Bor contained the highest total concentrations of Cu (516.14 µg g-1), Mn (553.46 µg g-1) and Sr (173.69 µg g-1). Igeo index exhibited moderate to heavy soil contamination. Up to 50.7% of Cutotal, 34.4% of Mntotal, and 27.3% of Srtotal were extracted in the phytoavailable pool. After the uptake, C. bursa-pastorispredominantly translocated PTEs to the aboveground parts, demonstrating accumulation in shoots, as the prevailing strategy. Principal Component Analysis indicated clear distinction based on sampling sites and the formation of separate clusters belonging to four cities. Moreover, Spearman correlation analysis revealed the significant interconnection among MPs and PTEs mobility in the soil-plant system. MPs positively correlated to Cu phytoavailable fraction in soils (ρ=+0.49) and with Cu content in shoots (ρ=+0.56). These findings provide insights into MPs-PTEs interactions, thereby contributing to a better understanding of potential environmental impacts
Potential effects of environmental microplastics on essential elements uptake by Capsella bursa-pastoris (L.) Medik.
No full textRecently, microplastics (MPs) in terrestrial ecosystems have attracted serious attention. MPs in soil may
adversely affect crop species, food web, and human health [1]. It was reported that soil MPs could
decrease Mg content in the roots of tomatoes (Lycopersicon esculentum L.) and reduce Ca in the stems
and leaves of pumpkin (Cucurbita pepo L.) [1, 2]. The present study investigated the potential impacts of
environmental MPs on the uptake of essential elements by traditionally used medicinal herb Capsella
bursa-pastoris (L.) Medik. Soil and plant samples were collected in Belgrade, Sremska Mitrovica, Vršac,
and Bor. MPs were isolated from soil by the optimized density separation method. Calcium (Ca),
potassium (K), and magnesium (Mg) contents were determined in roots and shoots of C. bursa-pastoris
by inductively coupled plasma optical emission spectroscopy (ICP-OES). No statistically significant
difference was found between sampling sites (Kruskal Wallis, p<0.05). Principal Component Analysis
(PCA) also showed no distinct clusters among samples from different locations, suggesting that plant
uptake was not affected by geographical region. C. bursa-pastoris mainly translocated Ca, K, and Mg to
the shoots. Shoots contained between 17.26 mg kg-1 and 21.22 mg kg-1 of Ca, 13.22–20.35 mg kg-1 of
K, and 1.61–2.05 mg kg-1 of Mg. Spearman correlation analysis revealed interconnection among MPs
abundance in soil and Ca, K, and Mg contents in plant roots and shoots. Soil MPs exhibited significant
negative correlations with Mg in roots (ρ=-0.92) and Ca in shoots (ρ=-0.95), indicating that MPs might
inhibit the Mg uptake and transfer of Ca within plant. This study provided insight into the potential
implications of environmental MPs on the mineral nutrition of medicinal plants, which are an integral part of the human diet. Further research is required to clarify the MPs influence on crop species and the food chain
Leaching of magnesium from serpentinite tailings
No full textThe demand for magnesium (Mg) and its alloys is increasing due to their use in various industries, including
recent applications of Mg compounds for CO2 sequestration. However, conventional methods for primary Mg
processing, such as thermal reduction and electrolysis, require considerable energy consumption and have a
significant environmental impact. On the other hand, the hydrometallurgical processes are considered more
environmentally friendly and economically viable, even for small-scale production. This paper explores the
potential of obtaining Mg from serpentinite minerals using a hydrometallurgical approach. The objective of
this study is to optimize the parameters of the leaching process with HCl acid solution. This is achieved through
thermodynamic calculations using the HSC Chemistry software. Chemical analysis of the serpentinite mineral
revealed a Mg content of 13.05%, and the presence of impurities (Fe, Ca, Al, Cr, Ni, etc.). This data served as
the basis for the thermodynamic calculations, while the amount of Mg compounds in the pregnant leached
solution is used to evaluate the efficiency of the leaching process. The optimization involved examining the
effects of temperature (ranging from 0 to 100 °C) and HCl acid addition (ranging from 0 to 15 mol). The study
concluded that temperature does not significantly affect the efficiency of Mg leaching. Instead, by selecting
the optimal amount of acid, it is possible to maximize Mg leaching while minimizing the presence of
impurities. However, further experimental investigation on the influence of other leaching parameters, such as
particle size and mixing speed, is needed
Uranium(VI) adsorption on natural and modified clinoptilolite mineral
No full textIn this paper the investigation results of adsorption of uranyl ion on unmodified and acid modified clinoptilolite are presented. Adsorption was investigated at different amounts of adsorbents in suspension, different concentrations of uranyl ion in solution, as well as at different pH values
Molecular docking's pioneering role in materials science. Metal ion site-preference in fluorapatite
No full textOriginally created for biological systems, molecular docking has pro-ven to be useful to predict metal ion binding locations and affinities in materials. By using this novel approach, it was possible to estimate the binding energies of Ca2+, Sr2+, Mn2+, Cu2+ and Pr3+ for two different calcium sites in fluorapatite. The data obtained from the crystal structures of doped fluorapatites showed a good agreement with the docking research. The interpretation of docking results was made easier by combining results from DFT calculations with geometrical analysis of crystal structures of small molecules. Notably, this strategy is more favourable than previously used theoretical approaches due to the computational efficiency and the demonstrated reliability
Comparative assessment of adsorbents performances of plant biomasses grown on different sites: case study of invasive Acer negundo L.
No full textWith the increasing global spread of invasive species, collecting their biomass could be a promising source for adsorbent development and water remediation. Therefore, the ability of adsorbent based on biomass of invasive plant Acer negundo L. originating from different habitat types was investigated for the lead removal from aqueous solution, in order to observe if different growing sites have effect on adsorbent performances. Three sites were selected for sampling: forest edges on Mt. Avala, riparian forests at Great War Island and banks of coal separation pond in Piskanja. Characterisation was performed via pHpzc, zeta potential, CEC, SEM-EDS and FTIR analysis. Optimization of sorption parameters was done and the best performance was at pH 5.0, adsorbent dosage 2.0 g/dm3 at 298 K for 60 min. Fitting of isothermal experiment data showed best correlation with Sips model (qmax is 94.92 - 131.52 mg/g, according to growing site). Among three reaction kinetic models, pseudo-second-order kinetics model showed best results. Since sample taken from the most anthropogenic influenced area have almost 30% lower adsorption capacity than others, it can be concluded that growing site characteristics reflect on biomass performances, which is important factor for any further biomass usage
Influence of mechanochemical activation on the sorption characteristics of sodium carbonate
No full textCarbon dioxide is a secondary product of many industrial systems, which significantly affects the increase in its content in the air. This carbon dioxide directly affects environmental pollution. Absorption of the obtained CO2 in industrial plants is very important in the process of environmental protection. It has been observed that sodium carbonate has the ability to absorb carbon dioxide, and that mechanochemical activation significantly enhances this property. In this work, sodium carbonate is a mechanical activation and its sorption properties are monitored by X-
ray diffraction and BET methods
Uklanjanje jona teških metala iz vodenih rastvora pomoću ugljeničnih materijala dobijenih iz otpadne biomase
No full textOтпадна биомаса представља вредан ресурс за производњу функционалних угљеничних материјала који се могу успешно применити у уклањању јона тешких метала из отпадних вода. У овом прегледном раду укратко су приказане најчешће коришћене биомасе за добијање биочађи и хидрочађи, њихова својства и ефикасност у уклањању загађивача из водених раствора. Биочађи и хидрочађи иако имају различите механизме деловања и адсорпциону ефикасност углавном уклањају металне јоне комплексирањем, разменом јона и електростатичким привлачењем. Резултати бројних студија показују да је биочађ најчешће ефикаснија за уклањање метала попут Cd²⁺ и Pb²⁺, док хидрочађи имају предност у погледу функционалније и еколошке производње. Будућа истраживања треба усмерити на оптимизацију, модификацију и класификацију материјала према циљаним применама