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Alkali Fusion–Leaching Process for Non-Standard Copper Anode Slime (CAS)
No full textCopper anode slime (CAS), obtained from non-standard anodes by pyro-hydrometallurgical
electronic waste (e-waste) processing, contains high concentrations of lead, tin (as metastannic acid), and base (Cu, Fe, Zn), precious (Au, Ag), and technological metals (In, Ga, Ge),
which limit the efficiency of conventional valorization methods. In this study, an integrated
alkali fusion–leaching process was applied to non-standard CAS. Thermodynamic modeling defined the key parameters for selective phase transformations and efficient metal
separation. These parameters were experimentally investigated, and the optimized fusion
conditions (CAS:NaOH = 40:60, 600 ◦C, 60 min), followed by water leaching (200 g/dm3
,
80 ◦C, 60 min, 250 rpm), resulted in >97% Sn removal efficiency. Simultaneously, Au and
Ag losses were negligible, resulting in solid residue enrichment. Oxidant addition (NaNO3)
did not improve Sn removal but increased Fe, Pb, and Ag solubility, reducing selectivity.
The scaled-up test confirmed process reproducibility, achieving 97.75% Sn dissolution and
retention of precious metals in the PbO-based residue (99.99% Au, 99.78% Ag). Application of an integrated thermodynamic modeling, laboratory optimization, and scaled-up
validation approach to non-standard CAS provides a relevant framework for a selective,
efficient, and scalable method addressing industrial needs driven by increased e-waste
co-processing, contributing to sustainable metal recover
Measurement and Correlation of Liquid–Liquid Equilibrium Data for Ternary Systems Water + Acetone + Organic Solvents (Isoamyl Acetate, or Ethyl Butyrate, or 1-Octanol, or 1-Decanol) at 298.15 K and Atmospheric Pressure
No full textOne of the major global challenges today is the management of wastewater, specifically the removal of pollutants that it contains. One of the key challenges in the industrial sector is substituting traditional solvents used in these processes with new, environmentally friendly alternatives as well as replacing conventional, energy-intensive separation methods. This study examines the possibility of acetone extraction using green organic solvents (isoamyl acetate, ethyl butyrate, 1-octanol, and 1-decanol), which are most often used as fragrances. Liquid-liquid equilibrium data for the four ternary mixtures of water + acetone + organic solvents at T = 298.15 K and atmospheric pressure are presented, providing the necessary thermodynamic data for process separation design. Binodal curves were obtained by using the cloud point titration method, while tie lines were determined through refractive index measurements. Distribution coefficients and separation factors were calculated for the immiscibility region. Othmer-Tobias and Hand correlations were used to assess the reliability of the experimental data. The experimental ternary LLE data were correlated using UNIversal QUAsiChemical (UNIQUAC) activity coefficient models. The results confirm that these green solvents are suitable choices for extracting acetone from water
Conifer Cone Extracts as Natural Antimicrobial and Prebiotic Agents: A Sustainable Biotechnological Solution
No full textIntroduction: The increasing demand for alternatives to synthetic
antimicrobial agents has prompted extensive research into natural bioactive
compounds with antimicrobial potential. These naturally derived agents
present a promising solution to antibiotic resistance by offering a safer, more
sustainable approach to microbial control, with broad applicability across
various industries. Notably, selected rare natural compounds demonstrate
both antimicrobial and prebiotic properties, facilitating the targeted
suppression of pathogenic bacteria while simultaneously fostering the growth
of beneficial microbial communities. This selective modulation of
microbiota composition may contribute to improved gastrointestinal
function, immune homeostasis, and overall systemic health
Production of polyphenol-rich fraction from rapeseed meal as a potential source of antioxidants and prebiotics
No full textIntroduction: Rapeseed is widely cultivated globally for oil production,
with the resulting by-product, rapeseed meal (RSM), ranking second only to
soy meal in volume. RSM is notable for its high protein content (35-40 %)
and, unlike other oilseed meals, is rich in sulfur-containing amino acids such
as methionine and cysteine. It also provides essential minerals and vitamins.
However, its inadequate to be used in animal or human diet due to the
presence of lignocellulosic fibers and antinutritional compounds, including
glucosinolates, phytic acid, and phenolic compounds (PCs). Nevertheless,
recent research highlights that many PCs extracted from plant based
byproducts provide health benefits and have antioxidative properties, and
therefore, it seems worth considering their application as potential prebiotics
Process for Simultaneous Removal of S8, DBDS, and PCBs From Mineral Insulating Oils
No full textThe presence of corrosive sulfur and polychlorinated biphenyls (PCBs) in mineral insulating oils poses significant challenge to the reliability of power transformers and presents serious environmental risks. Elemental sulfur (S8) and dibenzyl disulfide (DBDS) are well-known for causing the formation of metal sulfides on transformer components, leading to equipment failures, while PCBs present in insulating oils are persistent environmental pollutants with long-term health hazards. Current insulating oil purification techniques, including adsorbents, metal passivators and reagents, exhibit limited effectiveness, particularly if elemental sulfur is present in oil. This study introduces a novel reagent-based desulfurization process which uses copper deposited on iron particles dispersed in polyethylene glycol, for the complete removal of S8 from mineral insulating oil. The integration of S8 removal process with the KOH/PEG complex enables the simultaneous removal of S8, DBDS, and PCBs, with no residual metal particles detected in the oil following the treatment. Laboratory-scale experiments have shown the high efficiency of the developed process resulting in the improved physical-chemical and electrical properties of the oil, which was further verified on pilot scale unit and finally on the industrial scale process unit
Influence of Alkyd Composite Coatings with Polyaniline Doped with Different Organic Acids on the Corrosion of Mild Steel [Predavanje po pozivu]
No full textPredavanje po poziv
Prioritization and Sensitivity of Pesticide Risks from Root and Tuber Vegetables
No full textThis study investigated pesticide residues in 580 vegetable samples collected from markets in Serbia, encompassing potatoes, carrots, celery, radishes, horseradish, ginger, onions, and leeks. In total, 33 distinct pesticides were detected using validated HPLC-MS/MS and GC-MS/MS analytical methods. Multiple residues were identified in 19 samples, while 29 samples exceeded established maximum residue levels (MRLs). Acute and chronic dietary risks were assessed for both adults and children. Although individual hazard quotients (HQs) for adults and children remained below the threshold of concern (HQ < 1), the cumulative acute risk reached up to 63.1% of the Acute Reference Dose (ARfD) for children and 51.1% ARfD for adults, with ginger and celery posing the highest risks. Similarly, cumulative chronic risks remained below the safety threshold, with the Acceptable Daily Intake (ADI) percentages reaching a maximum of 5.9% ADI for adults and increased vulnerability of 11.0% ADI among children. Monte Carlo simulations were applied to account for variability and uncertainty in chronic exposure estimates. The hazard index (HI) results showed that adverse health effects for both population groups remained within acceptable safety limits (HI < 1), although higher susceptibility was observed in children. Sensitivity analysis identified body weight and vegetable consumption rates as the most influential factors affecting chronic risk variability
Prehrambene nanostrukture na bazi mešavine proteina lista bundeve i pululana kao potencijalni nosači za kobalamin
No full textNowadays, nanostructures made of biopolymers, such as proteins and polysaccharides, have gathered the growing attention of food scientists. In this study, pumpkin leaves from field crop side streams were processed to produce the protein isolate. The leaf protein isolate was investigated given the ability to encapsulate cobalamin (vitamin B12) in a blend with pullulan by electrospinning method. The starting blend solutions were characterized regarding the key factors that influence the formation of the fibers: viscosity, charge density carried by the jet, and surface tension. The results showed that the addition of the protein isolate (1% w/v) increased the conductivity of the pullulan solution (5% w/v), from 0.163 mS/cm to 1.420 mS/cm and the viscosity from 1.74±0.07 to 8.34±0.09 mPas. Cobalamin (at a concentration of 0.3 mg/mL) decreased the conductivity (0.978 mS/cm) and slightly increased the surface tension and viscosity of the final solution. SEM micrographs showed the formation of beads-on-fiber structures after the electro-hydrodynamic processing of the solutions. The protein caused the reduction of the beads compared to the beads obtained from neat pullulan (176.68 nm vs. 357.52 nm), while the mean fiber diameter was not affected (~22.5 nm). The combination of biopolymer pullulan and protein-rich pumpkin leaf extract has shown the properties of a potential carrier for the model vitamin.U današnje vreme nanostrukture pripremljene upotrebom prirodnih (zelenih)
proteina privlače sve veću pažnju naučnika koji se bave hranom. U ovoj studiji, listovi
bundeve koji predstavljaju otpadnu biomasu su iskorišćeni u cilju dobijanja proteinskog
izolata. Mešavina ovog izolata i biopolimera pululana ispitana je sa aspekta mogućnosti
inkapsulacije vitamina (vitamina B12) elektro-hidrodinamičkom metodom. Polazni rastvori
ispitani su u pogledu ključnih faktora koji utiču na formiranje vlakana: viskozitet, gustina
naelektrisanja koju nosi mlaz i površinski napon. Rezultati su pokazali da je dodavanje
proteinskog izolata (1% w/v) povećalo provodljivost rastvora pululana (5% w/v), sa 0,163
mS/cm na 1,420 mS/cm i viskozitet sa 1,74±0,07 do 8,34±0,09 mPa·s. Kobalamin (0,3 mg
mL-1
) je smanjio provodljivost (0,978 mS/cm) i blago povećao površinski napon i viskozitet
konačnog rastvora. Mikrografije elektronske mikroskopije su pokazale formiranje struktura
čestica na vlaknima nakon primene elektro-hidrodinamičke metode. Protein je izazvao
smanjenje čestica u poređenju sa česticama dobijenim od čistog pululana (176,68 nm
naspram 357,52 nm), dok srednji prečnik vlakna nije bio promenjen (~22,5 nm).
Kombinacija prirodnog biopolimera pululana i izolata listova bundeve bogatog proteinima
pokazala je svojstva pogodnog nosača za vitamin kobalamin
Bioactive Materials based on Calcium Phosphates and Mesoporous Bioglass ion-doped with Magnesium and/or Strontium: Synthesis, Processing, Characterization and Biomedical Application
No full textU okviru ove doktorske disertacije sintetisani su i ispitani prahovi na bazi kalcijum-fosfata
(CaP) i mezoporoznog bioaktivnog stakla (MBAG) dopirani jonima magnezijuma (Mg2+) i/ili
stroncijuma (Sr2+). Različitim metodama procesiranja, a polazeći od sintetisanih prahova, dobijeni su
kontrolisano porozni kompakti i makroporozni nosači ćelija, a u nastavku je ispitan njihov potencijal
za primenu u stomatologiji i biomedicini.
Pokazano je da istovremeno prisustvo jona Sr2+ i Mg2+ u strukturi hidroksiapatita (HAP)
destabiliše HAP rešetku, rezultujući bifaznim CaP sastavom, dok prilikom sinterovanja stabiliše b-
TCP fazu odlaganjem transformacije u a-TCP. Najbolja mehanička svojstva su potvrđena kod
SrMgHAP uzorka dopiranog sa po 3 mol.% Sr2+ i Mg2+ (5,02 GPa i 1,12 MPa‧m1/2).
Sferne nanočestice SrMgMBAG su uspešno sintetisane mikroemulzionom tehnikom. Binarno
dopiranje je uticalo na stvaranje radijalne dendritske mezoporozne strukture, što je ubrzalo otpuštanje
leka ibuprofena u poređenju sa nedopiranim česticama.
Procesirani kompakti kotrolisane poroznosti na bazi dopiranih HAP su ispitani za primenu u
stomatologiji u vidu dentalnih inserata. Predložen je novi protokol za restauraciju velikih kaviteta
zuba korišćenjem dentalnih inserata na bazi HAP. Ekstrahovani ljudski molari restaurirani
korišćenjem konvencionalnog postupka i primenom novog protokola su imali sličnu otpornost na
lom.
Dobijeni makroporozni nosači ćelija na bazi SrMgCaP i njihovi kompoziti sa MBAG
predstavljaju adekvatne nosače ćelija za primenu u inženjerstvu koštanog tkiva, omogućuju dobru
adheziju i proliferaciju BM-MSC i EA.hy926 ćelija, i pokazuju pro-osteogena i pro-angiogena
svojstva. Nanošenje biorazgradive biokompozitne prevlake na bazi želatina i čestica Sr,MgMBAG je
značajno poboljšalo pritisnu čvrstoću makroporoznih nosača.Within this doctoral dissertation powders based on calcium phosphates (CaP) and mesoporous
bioactive glass (MBAG) doped with magnesium (Mg2+) and/or strontium (Sr2+) ions were
synthesized. Using various techniques the obtained powders were processed in the form of compacts
with controlled porosity, or scaffolds, and their possible biomedical or dental application was
evaluated.
It was shown that simultaneous presence of Sr2+ and Mg2+ in the hydroxyapatite (HAP)
structure destabilizes the HAP lattice resulting in the biphasic CaP composition, while also stabilizing
the b-TCP phase during sintering by postponing its transformation into a-TCP. The best mechanical
properties were obtained in the case of SrMgHAP doped with 3 mol.% of Sr2+ and Mg2+ (5,02 GPa i
1,12 MPa‧m1/2).
Spherical SrMgMBAG nanoparticles were successfully synthesized using microemulsion solgel
technique. The binary doping influenced formation of radial dendritic mesoporous structure,
which increased the rate of ibuprofen drug release, compared to pristine particles.
Obtained compacts with controlled porosity based on doped HAP were analyzed for
application in dentistry as dental inserts. A novel protocol for restoration of large tooth cavities using
dental inserts based on HAP was proposed. Extracted human molars were restored using convectional
and novel protocols, and their fracture resistance was shown to be similar.
Fabricated scaffolds based on SrMgCaP and their composites with MBAG were shown to be
adequate cell carriers for application in bone tissue engineering, by showing good cells adhesion and
proliferation of BM-MSC and EA.hy926 cells, as well as pro-osteogenic and pro-angiogenic
properties. Coating the scaffolds with biodegradable biocomposites based on gelatine and
SrMgMBAG particles showed significantly improved compressive strength of the scaffolds
Quantification of volatile fatty acids to safeguard reclaimed water quality
No full textEscalating water scarcity has driven the global expansion of water reuse, yet trace-level volatile organic compounds, including volatile fatty acids (VFAs), challenge public acceptance and ecosystem health. Their sour odors at low concentrations signal treatment barrier breakthrough or contamination, threaten aquatic ecosystems, promote eutrophication, and contribute to greenhouse gas emissions. Conversely, VFA-rich side streams from biological treatment can be valorized within circular water wastewater biorefineries: recovering VFAs enables polyhydroxyalkanoate production, enhances biological phosphorus removal, and feeds anaerobic co-digestion for biogas. By coupling validated analytics with by-product recovery and upcycling, operators align water reuse with circular-economy principles, thus protecting human and environmental health while generating marketable polymers and energy.
This study developed and validated a suppressed-ion chromatography protocol using an anionexchange column under isocratic conditions for routine quantification of nine VFAs (lactic, formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, and caproic acid) in reclaimed water. Calibration standards spanning 1
range, detection limits, precision, accuracy and recovery. The method demonstrated excellent linearity (R² > 0.995), low detection limits in the single- - and interday relative standard deviations below 5%, with recoveries of 70 120% for most analytes in both municipal wastewater and permeate samples. The protocol is cost-effective, time-efficient, and requires no extraction or organic solvents. These performance metrics confirm its robustness for real-time quality control in water reuse scenarios.BeCELS 2025: Belgrade Conference for Early-Career Life Scientists, taking place on Friday, September 5, 2025, at the Institute of Molecular Genetics and Genetic Engineering (IMGGE) in Belgrad