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Removal of xenobiotics from wastewaters using photolysis under sun-light irradiation: experimental approach and process design
No full textConventional wastewater treatment processes are increasingly difficult to fulfill strict standards of
achieving the required quality. Therefore, it is necessary to apply processes that in an efficient and
economically justified way reach the necessary limits in order to discharge wastewater into the
recipient. The process of photolysis represents the degradation of the starting pollutant practically to
water and carbon dioxide. The whole process takes place under the action of a UV lamp that imitated
solar irradiation. The process is environmentally justified since, unlike some other advanced
oxidation processes - AOPs, there is no use of additional, hazardous, chemicals which possibly results
in the precipitates formation that are leading to further treatment. In this paper, photolytic degradation
of pesticide thiophanate methyl was performed in doubled wall quartz reactor equipped with a
thermoregulation system. Reaction was forced under Osram ULTRA VITALUX UV lamp (300W).
Kinetics of photodecomposition process was followed by pseudo-first order. In certain time periods,
specimens were sampled, filtered and monitored by UV spectrophotometer Shimadzu 1800 with an
aim to determine the concentration of xenobiotic. Complete degradation of present xenobiotics was
obtained after 240 min. With an aim to enhance the degradation process, hydrogen peroxide was
added as a boosting agent which cause a shortening in demanded time (150 min) for complete
degradation. Verification of the success of decomposition was confirmed by the obtained values of
chemical oxygen demand (COD), which reveal that the established system has a basis for real
application in industrial or municipal wastewater
Naučna stručna validacija bentonitskog mineralnog resursa, na osnovu fizičko-hemijskih i mineraloških ispitivanja uzorka bentonita iz ležišta „Bijelo Polje“ – opština Bar
No full textU ITNMS-u su obavljena detaljna fizičko-hemijska i mineraloška ispitivanja na 3 tri vrste uzorka bentonita iz ležišta „Bijelo polje “- Opština Bar. Ova ispitivanja su omogućila sagledavanje potencijalnosti mineralnog resursa kao i tehnoloških mogućnosti prerade bentonitske sirovine iz ležišta "Bijelo Polje"-Bar u cilju dobijanja komercijalnih proizvoda, za primenu u različitim industrijskim granama. Ovim ispitivanjima su određeni: gruba i higroskopna vlaga, specifična masa, granulometrijski sastavi. Granulometrijski sastavi su određivani prosejavanjem na Tyler-ovoj seriji sita, do krupnoće -37μm, a na klasi -37+0,00μm granulometrijski sastavi su određeni laserskom difrakcijom na suvo i mokro. Na sve tri vrste uzoraka obavljene su hemijske analize, u okviru kojih je određen sadržaj glavnih i štetnih komponenti u uzorcima bentonita (sadržaj teških metala). U okviru fizičke karakterizacije urađena je DTG/TG i DSC analiza, određen je: bentonitski broj, KKI (kapacitet katjonske izmene), stepen adsorpcije metilen plavog, stepen beline pojedinih uzoraka, kao i index plastičnosti po metodi Atteberg-Kasagrande, koef. apsorpcije vlage po metodi Enslin –Neff, sadržaj adsorbovanih dioksina u kompozitnom uzorku bentonitske rude, i na kraju je obavljeno određivanje pH vrednosti 5% suspenzije. U okviru mineraloških ispitivanja obavljena su ispitivanja na pojedinim klasama krupnoće, kao i XRD analiza, kojom su određene strukturno-teksturne osobine bentonitske sirovine, mineralni sastav, način njihovog pojavljivanja, veličinu pojedinih mineralnih čestica u rudi itd. Sve obavljene analize i ispitivanja izvrsena su u skladu sa medjunarodno priznatim standardnim metodama za odredjivanje parametara koji se koriste za ocenu kvaliteta bentonitski glina - ISO, EN i ASTM. Obavljena ispitivanja su pokazala da je bentonitski mineralni resurs „Bijelo polje “- Bar, veoma značajna sirovina iz koje se mogu dobiti brojni proizvodi koji se mogu potencijalno primeniti u mnogim industrijskim granama
Implementation of information technologies in mining and sustainable development
No full textU radu je prikazan značaj uvođenja informacionih tehnologija (IT) u oblast rudarstva, kao i
značaj održivosti tehnologija i održivog razvoja. Savremenim tehnologijama prevazilazi se konvencionalni
način eksploatacije mineralnih sirovina što direktno utiče na povećanje, kako obima proizvodnje, tako i
ostvarenog profita. Međutim, mora se voditi računa o održivosti same tehnologije i održivom razvoju što
direktno doprinosi održivosti prirodnih resursa. Prirodni resursi su neobnovljivi ili teško obnovljivi i zato je
veoma važno analizirati sve aspekte uvođenja novih tehnologija. Neophodna je planska i kontrolisana
eksploatacija svih mineralnih sirovina. Takođe, sve rudarske aktivnosti mogu da imaju negativan uticaj na
životnu sredinu i trajno degradiraju prostor gde se vrši eksploatacija. Uvođenjem novih tehnologija stvara se
mogućnost praćenja svih parametara relevantnih za procenu tih uticaja. Svetske kompanije su u obavezi da
svojom transparentnošću u poslovanju obezbede uvid u moguće ekološke posledice svog poslovanja i ukažu na
mere koje će preduzeti u cilju njihovog sprečavanja. Jedino na taj način rudarski sektor može da bude
pozicioniran kao moderan i okrenut održivoj ekonomiji u budućnosti. Na koji način će se poslovanje
prilagoditi današnjem modernom pristupu organizacije zavisi od sposobnosti menadžmenta da ažurira
informacije u realnom vremenu, donosi odluke i izvršava ih na vreme. Usvajanjem informacionih praksi i
automatizovane tehnologije povećava se učinak aktivnosti koje menadžment sprovodi. Uopšteno govoreći,
održivost, bez obzira da li se radi o menadžmentu, tehnologiji ili razvoju, je sposobnost održavanja ravnoteže
određenih procesa ili stanja u nekom sistemu bez obzira na tehnološki napredak i modernizaciju poslovanja.
Status održivosti imaće samo ono što uvek daje pozitivne rezultate i nema negativnih posledica na ljude,
životni prostor, ekosisteme i biljni i životinjski svet. Održivi razvoj i informacione tehnologije, koje se brzo
razvijaju, su usko povezani. Informacione tehnologije su pokretač globalizacije i povezivanja na svim
nivoima. Zato je danas moguće uraditi sistematsku procenu direktnih i indirektnih uticaja primenjenih
tehnologija na životnu sredinu. Polazna platforma je interakcija ekonomskih, ekoloških i društvenih pitanja.
Društvo mora da raspolaže informacijama o potencijalnom riziku i uticaju na održivi razvoj, posebno kada
se radi o životnoj sredini. Koliko je to značajno svetska naučna javnost je pokazala uvođenjem tzv. informatike životne sredine. Informatika životne sredine je disciplina primene informacionih i komunikacionih
tehnologija u istraživanju, planiranju i zaštiti životne sredine. Njen osnovni cilj je da se sva naučna otkrića u
bazičnim naukama i informacionim tehnologijama primene za rešavanje različitih ekoloških problema. Na
taj način se unapređuje i stvara sve jača sprega između nauke i tehnologije i daje doprinos razvoju održivih
rešenja koja su naučno utemeljena i ekonomski isplativa
Improved technology for production of PE and PP regranulates
No full textManagement of waste polymers (polyethylene - PE and polypropylene - PP) represents one of the major
obstacles in the field of environmental protection, which demands a most efficient and eco-friendly
technological solution. Due to the high use of various plastic materials, the amount of landfilled or
dissipated plastic waste is continuously growing. Therefore, this paper examines the possibilities of
recycling these polymers, alongside obtaining granules of similar or advanced physico-mechanical
characteristics to the commercially available ones. The applied technology consists of several
consecutive processes (collecting, grinding, washing and extruding) where the obtained materials can
later be incorporated into widely applicable products, such as foils, bin liners, bags, among others. In
this way, high-quality products with great market potential are obtained, which will consequently
contribute to lower extraction and less depletion of natural resources. Thus major problems may be
solved optimally, consolidating the efficiency of improved eco-friendly technologies which is in line with
environmental protection and sustainable waste management
Fatty acids composition and physical properties of stones and kernels from different peach cultivars as biomarker of origin and ripening time
No full textThe peach stones and kernels are easily available biowaste which could be useful for the extraction of nutritionally important compounds such as fatty acids. Except in industry, characterization of stones and kernels could be useful in pomology to describe different cultivars, and for selecting new parents in a breeding program. A total of 25 samples of stones and kernels from various peach cultivars that differed in origin and ripening time, but growing in the same climatic conditions, were characterized by fatty acids composition and physical properties. This work confirmed that unsaturated fatty acids (oleic and linoleic fatty acids) were the most represented in peach kernel oil and their content depended of peach genotype. Additionally, the fatty acids in combination with length, weight, and moisture of peach kernels could be used as a parameter of authenticity assessment. This research may contribute for the peach cultivar discrimination and recommendation of cultivars/genotypes with high kernel quality which could be used for the extractions of oil rich in unsaturated fatty acids and further use in food, pharmaceutical and cosmetic industry. Besides, selected cultivars could be used in breeding programs, for creating new genotypes for oil production
Coordination preferences of NNO and NNS Schiff base ligands with Co(III) complexes: Synthesis, characterization and DFT calculation
No full textTwo Co(III) complexes with condensation product of thiosemicarbazide and 2-acetylthiazole ( HL 1 ligand, ( E )-2-(1-(thiazol-2-yl)ethylidene)hydrazine-1-carbothioamide) and the condensation product of 2-acetylpyridine and Girard's P reagent ( HL 2 Cl ligand, ( E )-1-(2-oxo-2-(2-(1-(pyridin-2yl)ethylidene)hydrazinyl)ethyl)pyridin-1-ium chloride) have been synthesized and characterized based on the results of single-crystal X-ray diffraction, NMR and IR spectroscopy and elemental analysis. Cobalt(III) complex with HL 1 ligand, [Co( L 1 ) 2 ]BF 4 center dot H 2 O ( 1 ), is bis octahedral complex in which two deprotonated ligand molecules coordinate in a mer arrangement through two NNS sets of donor atoms. In cobalt(III) complex with HL 2 Cl, [Co( L 2 )(N 3 ) 3 ] ( 2 ), the ligand is coordinated in deprotonated, formally neutral, form to Co(III) ion in tridentate fashion through NNO set of donor atoms, and the other three coordination sites of a monokis octahedron are occupied by meridionally coordinated azide anions. DFT calculations were performed to elucidate coordination preferences of these ligands toward Co(III) ion
Original scientific paper examination of influence sintering temperature on mineral compounds
No full textMineral materials, such as corundum, quartz and periclase are very often used in technological processes. Due to its characteristics, and chemical reaction in solid state, these minerals form very interesting and useful material, cordierite. The mineral ratio in this compound (MgO : Al2O3 : SiO2) is 2:2:5. They form cordierite, electronic ceramic, which can be sintered in a narrow temperature range, at about 1375 °C. Composition of this electronic ceramics material is is 2MgO-2Al2O3-5SiO2 (MAS) and in this research 20% mass Bi2O3 was added in the aim of decrease the sintering temperature. The effects of sintering, the composition and morphology were followed by x-ray diffraction, scanning electron microscopy and EDS analysis, as a function of sintering temperature. MAS ceramics were sintered at 1000ºC, 1100ºC and 1200ºC
Adsorption of estrone, 17 beta-estradiol, and 17 alpha-ethinylestradiol from water onto modified multi-walled carbon nanotubes, carbon cryogel, and carbonized hydrothermal carbon
No full textCarbon materials of different structural and textural properties (multi-walled carbon nanotubes, carbon cryogel, and carbonized hydrothermal carbon) were used as adsorbents for the removal of estrone, 17 beta-estradiol, and 17 alpha-ethinylestradiol from aqueous solutions. Chemical modification and/or activation were applied to alter surface characteristics and to increase the adsorption and desorption efficiency of carbon materials. Surfaces of treated and untreated carbon materials were characterized through the examination of the textural properties, the nature of surface functional groups, and surface acidity. It was found that the adsorption capacity of tested carbon materials is not directly proportional to the specific surface area and the content of surface oxygen groups. However, a high ratio of surface mesoporosity affected the adsorption process most prominently, by increasing adsorption capacity and the rate of the adsorption process. Adsorption of estrone, 17 beta-estradiol, and 17 alpha-ethinylestradiol followed pseudo-second-order kinetic model, while the equilibrium adsorption data were best fitted with the Langmuir isotherm model. Calculated mean adsorption energy values, along with the thermodynamic parameters, indicated that removal of selected hormones was dominated by the physisorption mechanism. High values of adsorption efficiency (88-100 %) and Langmuir adsorption capacities (29.45-194.7 mg/g) imply that examined materials, especially mesoporous carbon cryogel and multi-walled carbon nanotubes, can be used as powerful adsorbents for relatively fast removal of estrogen hormones from water
Bioactive hydroxyapatite/chitosan/poly(vinyl alcohol)/gentamicin composite coating electrodeposited on titanium
No full textTitanium (Ti) is an implant material widely used in orthopedics due to its high corrosion
resistance (naturally forms a passive oxide layer) and good mechanical properties. Although
Ti has certain ability to osseointegrate, the biocompatibility and bioactivity of Ti can be
significantly improved by modifying its surface. In order to improve antibacterial properties
a broad spectrum antibiotic gentamicin was loaded in a composite coating of hydroxyapatite
(HAP) with natural polymers chitosan (CS) and poly(vinyl alcohol (PVA) and was deposited
on Ti using electrophoretic deposition (EPD) technique. EPD was carried out at the constant
voltage on pure titanium plates from an aqueous suspension. Deposited HAP/CS/PVA and
HAP/CS/PVA/Gent coating were characterized by X-ray diffraction (XRD), Fourier
transform infrared spectroscopy (FT-IR), and field emission scanning electron microscopy
(FE-SEM). The obtained results confirmed the formation of new composite coatings.
Cytotoxicity against two types of cell lines (MRC-5 and L929) was investigated using trypan
blue dye-exclusion test (DET) and MTT assay for assessing cell metabolic activity. The
antibiotic loaded coating (HAP/CS/PVA/Gent) exhibited good antibacterial activity against
Staphylococcus aureus and Escherichia coli, while preserving low cytotoxicity, indicating
the high potential for biomedical applications. Excellent osteogenic properties, through the
promotion of osteoblast differentiation were confirmed by ALP assay. Results were much
more pronounced for HAP/CS/PVA/Gent coating. Therefore, HAP/CS/PVA/Gent coating
can be considered as an excellent promising candidate for biomedical hard tissue implants
Valorizacija otpadne biomase za proizvodnju efikasnih adsorbenata teških metala hidrotermalnom karbonizacijom
No full textPrimenom zelene tehnologije hidrotermalne karbonizacije (HTC) vlažna tpadna biomasa može se efikasno konvertovati u hidročađ (HC), proizvod sličan uglju, odličnih adsorpcionih karakteristika. HC iako niže poroznosti u odnosu na omercijalne biougljeve, veoma su bogate reaktivnim kiseoničnim funkcionalnim rupama (KFG) koje imaju značajnu ulogu u adsorpciji neorganskih polutanata. Adsorpcija primenom HC miskantusa dobijene HTC-om na 180°S je ispitivana klanjanjem Cu+2, i NH4+ iz vodenih rastvora pri čemu su postignuti maksimalni apaciteti uklanjanja od 310 i 71 mg/g, respektivno. Da bi se dodatno poboljšala posobnost sorpcije teških metala, ispitivane su različite metode aktivacije sovršinske strukture HC. Alkalni tretman HC komine grožđa dobijene HTC-om na 20°S poboljšao je kapacitet uklanjanja Pb+2,Cd+2 i Cu+2 iz vodenog rastvora pet puta, a 137, 49.3 i 38.2 mg/g, respektivno. Kalcifikacijom HC supstrata za gajenje gljiva, obijene HTC-om na 200°S, dizajniran je nov adsorbent Sa-piro-HC za Pb+2 i Cd+2 297 mg/g i 131 mg/g, respektivno). Dobijanjem visoko efikasnih adsorbenata iz tpadne biomase primenom HTC, može se podstaći saniranje problema zagađenja vode, zemlje, i vazduha u Srbiji