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Lead in atmospheric precipitation: Analysis of atmospheric precipitation pollution monitoring data for location "Kamenički vis", Serbia
No full textU radu je dat pregled rezultata praćenja sadržaja olova u atmosferskim padavinama uzorkovanim na GAW/EMEP (Global Atmosphere Watch/European Monitoring and Evaluation Programme) stanici "Kamenički vis" u periodu od 2000. do 2010. godine. Predstavljene su godišnje aritmetičke srednje vrednosti, godišnje težinske srednje vrednosti i medijana dobijenih srednjih nedeljnih vrednosti koncentracija olova u padavinama. Dobijeni podaci su upoređeni sa rezultatima analiza padavina na eksperimentalnoj EMEP stanici "Zeleno brdo", i diskutovani u odnosu na prosečni sadržaj olova u padavinama i vazduhu u Evropi. Predstavljeni rezultati ukazuju na to da je u periodu od 2000. do 2010. godine na posmatranoj lokaciji došlo do značajnog povećanja koncentracije olova u padavinama u 2003, a zatim i u 2007. godini, i da su uočena povećanja najverovatnije lokalnog karaktera. Radi sagledavanja mogućeg pravca i izvora iz kog potiču detektovane količine olova urađena je i kraća analiza emisije olova u zemljama u okruženju u datom periodu.In this paper, an overview of data collected during monitoring of lead content in atmospheric precipitation on GAW/EMEP (Global Atmosphere Watch/European Monitoring and Evaluation Programme) station "Kamenički Vis", Serbia from 2000 to 2010 is given. Annual arithmetic mean concentrations, weighted arithmetic mean concentrations, and median of week samples are presented. Obtained data was compared with results of analysis of atmospheric precipitation collected on experimental EMEP station "Zeleno brdo", Serbia and discussed in the scope of European average levels of lead content in precipitation and air. Significant increase of average annual lead content in precipitation was observed in 2003 and 2007. The observed peaks cannot be seen on average European trends, thus leading to the conclusion that the recorded increases are characteristic for the local region. In order to further discuss the nature and direction of possible sources of detected lead pollution, a short analysis of lead emission data was performed. An effort was made to gather data from the countries that lay in directions from which dominant winds blow, as well as for Serbia. For this purpose, total national emissions from LRTAP Convention emission inventory report and EMEP emission inventory were used, as well as data published by relevant national authorities. According to these emission levels, the majority of the surrounding countries couldn't have contributed much to the recorded increases of lead content in precipitation. However, several possible sources were revealed. In all studied countries, emission levels steadily dropped during the analyzed period, whereas only for Serbia a different trend was observed. The presented data leads to the conclusion that the recorded increase of lead content in precipitation in 2003 probably originates from trans-boundary contributions, while increases in 2007 and onwards may come from Serbia's own emissions
Biosorption of mycotoxins by waste biomass
No full textU radu su prikazani rezultati in vitro istraživanja mogućnosti korišćenja otpadne biomase vodenog korova Myriophyllum spicatum (M.spicatum, krocanj ili drezga) i koštica voća (breskva i višnja), u prirodnom i modifikovanom obliku, kao potencijalnih biosorbenata mikotoksina. Indeks biosorpcije je ispitivan na pH 3.0;6.9 i 7.0 u elektrolitu 0.1 M K2HPO4. Visok indeks biosorpcije aflatoxina B1 (AFL B1) utvrđen je za algu M. spicatum (94,70 odnosno 96,00 %). Nemodifikovane koštice breskve su vezivale manje količine AFL B1 (73.30 odnosno 80.00 %) dok je kod koštice višnje adsorpcija istog mikotoksina bila vidno slabija (58,82 odnosno 41,18%). Vrednosti biosorpcije za ohratoksin A (OTA), imale su, zavisno od biosorbenta i pH, izražena variranja (od 20.00 do 76.20 %). Najveći afinitet prema vomitoksinu (DON), imale su nemodifikovane koštice breskve (50 %), pri pH 6.9, a prema zearalenonu (ZON) vodeni korov M. spicatum (70 odnosno 75%). Afinitet prema diacetoksiscirpenolu (DAS), iako znatno slabiji, utvrđen je na obe pH vrednosti kod modifikovane koštice breskve (16.67 odnosno 33.33%) i modifikovane koštice višnje (16.67%). Podjednako dobar afinitet prema T-2 toksinu utvrđen je kod modifikovane koštice breskve i koštice višnje u nemodifikovanom i modifikovanom obliku (50.00 odnosno 40.00 %); pri nižoj pH vrednosti (3.0) upotrebljenog elektrolita afinitet prema ovom mikotoksinu je bio veći. Ostvareni rezultati ukazuju da su ispitivane otpadne biomase u prirodnom ili modifikovanom obliku bile efikasni biosorbenti pojedinih mikotoksina sa najvećim afinitetom prema AFL B1.The paper presents the results of in vitro studies of the possibility of using waste plant materials: biomass of aquatic weed Myriophyllum spicatum (Eurasian watermilfoil or spiked watermilfoil) and fruit stones (peach and sour cherry) in a natural and chemicaly modified form, as a potential biosorbents of different mycotoxins. Biosorption indexes were examined at pH 3.0, 6.9 or 7.0, respectively in electrolite 0.1 M K2HPO4. The highest biosorption indexes of aflatoxin B1 (AFL B1) were determined by algae M. spicatum (94.70 and 96.00%, respectively). Unmodified peach stones binded less quantities of AFL B1 (73.30 and 80.00%, respectively) while sour cherry stones adsorbed the smallest quantity af applied AFL B1 (58.82 and 41.18 %, respectively). The values of biosorption for ochratoxin A (OTA) varied a grait deal, dipending on the biosorbent type and pH values (20.0076.20%). The best affinity to vomitoxin (DON-in), was observed by unmodifiedpeache stones (50%), at pH 6.9, and for zearalenone (ZON) by M. spicatum (70 and 75%, respectively). Binding of diacetoxyscirp enol (DAS), although much weaker, was recorded at both pH values of applied electrolite by modified peache stones (16.67 and 33.33%, respectively) and modified sour cherry stones (16.67%). Equally good affinity for T-2 toxin was found in modified peache stones, and unmodified and modified form of sour cherriy stones (50.00 and 40.00%, respectively); at lower pH value (3.0) adsorption of this mycotoxin was more pronaunced. Presented results indicate that the tested waste biomasses, in the natural or modified form, were effective biosorbents of different mycotoxins with the highest affinity for AFL B1
Raw phosphate composite as a natural fertilizer and soil remediation amendment
No full textNaša istraživanja su bila usmerena ka dizajniranju novog multifunkcionalnog materijala na bazi sinergističkog dejstva sirovog fosfata i modifikovanog zeolita amonijum jonima i otpadne biomase, u cilju povećanja fosfo-mobilizacije u različitim tipovima zemljišta i širokom opsegu pH vrednosti Efikasnost je ispitana na vegetacionom ogledu sa biljkama kukuruza u polukontrolisanim uslovima , na tipu zemljišta, distrični kambisol. Rezultati ukazuju da dodavanje modifikovanog zeolita i pepela koštica višnji, prirodnom fosfatu, doprinosi rastu, razvoju i povečanju prinosa ispitivane kulture. Otpušteni fosfatni joni imali su dvostruku ulogu kao donor hranljivih materija i remedijacioni agens mehanizmom fosfatno -indukovane stabilizacije teških metala. Rezultati ukazuju da kompozit NH4+ - zeolit/prirodni fosfat ima multifunkcionalna svojstva pogodna za u održivoj poljoprivredi.Our investigation is focused on the design of novel multifunctional material based on the synergistic conjunction of raw phosphate, zeolites modified with ammonium ions and waste biomass, in support to increase phospho-mobilization in various soil types and wider pH range. The results of the vegetation experiment in semi-controlled conditions with maize on soil type distric cambisol indicates that the addition of modified zeolite and ash pit cherries to the rock phosphate favors the growth of the culture and its yield. Released phosphate ions have a dual role as donor of nutrients, and soil remediation amendment through phosphate-induced stabilization of heavy metals. The field vegetation experiment with maize on soil type leached chernozem showed that NH4+-zeolite/raw phosphate composite has multifunctional properties applicable in sustainable agriculture
Renewable silver-amalgam film electrode for voltammetric monitoring of solar photodegradation of imidacloprid in the presence of Fe/TiO2 and TiO2 catalysts
No full textA rapid and sensitive voltammetric method has been developed for the characterization and determination of the imidacloprid insecticide by means of square-wave voltammetry (SWV) with a silver-amalgam film electrode (Hg(Ag)FE) in the aqueous Britton-Robinson buffer solution as the supporting electrolyte. In the investigated pH range between 2.0 and 9.0 two reduction peaks of imidacloprid were observed, and they were both obtained in a fairly negative potential range, (approximately from -0.8 to -1.5 V). Their shape strongly depended on the pH of the supporting electrolyte. The analytical measurements, based on the first peak, were performed at the pH of 7.0, and imidacloprid was determined in the concentration range of 0.91-47.48 mu g cm(-3). The reproducibility of the analytical signal was characterized by a relative standard deviation smaller than 1.0%, and the calculated values of detection and quantitation limits were 0.27 mu g cm(-3) and 0.91 mu g cm(-3), respectively. The applicability of the elaborated SWV method was tested by monitoring imidacloprid concentration during its solar photolytic and photocatalytic degradation in the presence of two heterogeneous catalysts: TiO2 and TiO2 modified with 1.9% w/w Fe (1.9% Fe/TiO2). Under photolytic conditions, imidacloprid degraded very slowly, and the presence of TiO2 as a catalyst accelerated the process, while 1.9% Fe/TiO2 showed a remarkable efficiency in the removal of imidacloprid under natural insolation. In all investigated cases the results obtained using the Hg(Ag)FE-SWV method were in agreement with those obtained by means of the comparative HPLC-DAD method, which confirmed that the developed voltammetric method can be used to monitor the degradation of imidacloprid
Thermal study and mechanism of Ag2S oxidation in air
No full textThe results of thermal study and mechanism of the oxidation process of synthetic Ag2S in air are presented in this article based on the comparative analysis of DTA and XRD results, as well as by constructed phase stability diagrams (PSD) for the Ag-S-O system
Effect of pollutants on wet deposition characteristics
No full textPrecipitacija, a pre svega mokra depozicija, predstavlja jedan od najznačajnijih mehanizama za uklanjanje gasova iz atmosfere kojim se kontroliše njihova distribucija, koncentracija i životni vek u zemljinoj atmosferi. Formiranje i karakteristike precipitacije su pod snažnim uticajem atmosferskih (meteoroloških) uslova, međutim, značajnu ulogu mogu da imaju i zagađujuće materije, bilo da su nastale prirodnim ili veštačkim putem. Antropogene aktivnosti od industrijske revolucije na ovamo dovele su do značajnog povećanja koncentracija zagađujućih materija u atmosferi, a samim tim i do povećanog uticaja zagađujućih materija na osnovne meteorološke parametre. U ovom radu je dat pregled osnovnih zagađujućih materija koje nastaju ljudskim aktivnostima, a mogu da utiču na precipitaciju. U radu su razmatrane njihove karakteristike, način na koji nastaju i njihov uticaj na klimatske parametre. Posebna pažnja je posvećena konkretnim uticajima na mokru depoziciju, kao i promenama koje ona izaziva u životnoj sredini.Precipitation and primarily, wet deposition represents one of the most important mechanisms for gases removal from the atmosphere, and thus for control the distribution, concentration and life-time of many gaseous species in the atmosphere. Formation and characteristics of precipitation are heavily influenced by atmospheric (meteorological) conditions, but pollutants arising from natural and artificial sources can also have significant role. Anthropogenic activities from industrial revolution up to now led to a significant increase in the concentration of pollutants in the atmosphere and, therefore to increased influence of pollutants on main meteorological parameters. The paper gives an overview of main pollutants resulting from human activities, which could affect the precipitation. The paper discusses their characteristics, the way they occur and their impact on climate parameters. Special attention was paid to effects of pollutants on wet deposition, as well as on changes it causes in the environment
Recycling of nickel based hazardous waste from the plant oils industry
No full textU radu su prikazani rezultati reciklaže opasnog otpada na bazi nikla koji nastaje u procesu hidrogenovanja ulja. Kataloizatori na bazi nikla se koriste za selektivno hidrogenovanje biljnih ulja visoke aktivnosti. Istrošeni katalizatori na bazi nikla su svrstani u kategoriju H11 opasnih materija, koji se nakon završenog procesa, trenutno deponuju na prostoru generatora i na taj način predstavljaju potencijalnu opasnost po životnu sredinu. Eksperimentalnim istraživanjima definisani su optimalni uslovi (temperatura, vreme, odnos Č:T) tehnološkog postupka reciklaže istrošenih katalizatora. Izdvajanjem nikla u obliku nikl-sulfata opasan otpad prelazi u kategoriju neopasnog, a dobijeni proizvod ima komercijalnu vrednost. Stepen iskorišćenja nikla je veći od 95%.The results obtained during the recycling of spent nickel based catalysts that generate in the oil hydrogenation process are presented. Nickel based catalysts are used for selective hydrogenation of the highly active plants oils. The used catalysts are classified in the H11 category of hazardous materials; they are deposited on the site and are potentially dangerous to the environment. Laboratory experimental research defined optimal conditions (temperature, time and solid-liquid ratio) and technological process of catalysts recycling. Hazardous waste is being converted to the category of non-hazardous, and extracted nickel as nickel-sulphate represents commercial product. The degree of recovery of nickel is higher than 95%
Sulfosalt minerals from the Srebrenica orefield, Podrinje metallogenic district, East Bosnia
No full textDosadašnja ispitivanja pokazala su da se u rudnom polju Srebrenice javljaju izuzetno složene mineralne parageneze i asocijacije, gde u njima većim delom dominiraju raznovrsni minerali iz grupe sulfosoli. One su podeljene u šest sulfosolnih sistema: (i) Pb-(±Fe,±Cu)-(Sb,±As)-S (geokronit, bulanžerit, semseit, heteromorfit, tvinit, džemsonit, burnonit, bertijerit); (ii) Pb(Fe)-Sb-Ag-S (andorit, fizelit); (iii) Pb-(±Fe,±Cu,±Ag)-(Bi, Sb)-S (ferokobellite); (iv) (Cu,Ag)-(Fe,Zn)-(Sn,±In)-S (stanit, petrukit, kesterit, ferokesterit); (v) (Cu,Ag)-(Fe, Zn)-(Sb,As)-S (Ag-tetredrit, frajbergit); (vi) (Ag,±Cu,±Fe)-(Sb, As)-S (polibazit, stefanit, pirargirit, prustit). Utvrđeno je više etapno stvaranje minerala, gde prvoj etapi odgovara pneumatolitsko-hidrotermalna, a drugoj hidrotermalna, sa većim brojem stadijuma i podstadijuma.Previous research shown that in the Srebrenica orefield appear extremely complex mineral parageneses and associations in which minerals from the sulfosalt group dominate. These are divided in six sulfosalt mineral systems: (i) Pb-(±Fe,±Cu)-(Sb,±As)-S (geocronite, boulangerite, semseyite, heteromorphite, twinnite, jamesonite, bournonite, berthierite); (ii) Pb(Fe)-Ag-Sb-S (andorite, fizelyte); (iii) Pb-(±Fe,±Cu,±Ag)-(Bi,Sb)-S (ferrokobellite); (iv) (Cu,Ag)-(Fe,Zn)-(Sn,±In)-S (petrukite, kesterite, ferrokesterite, stannite); (v) (Cu,Ag)-(Fe,Zn)-(Sb,As)-S (argentian tetrahedrite, freibergite); (vi) (Ag,±Cu,±Fe)-(Sb,As)-S (polybasite, stephanite, pyrargyrite, proustite). The minerals were formed in several stages; the first stage corresponds to pneumatolic-hydrothermal, the second to hydrothermal, with large number of stadiums and substadiums
The adsorption of salicylic acid, acetylsalicylic acid and atenolol from aqueous solutions onto natural zeolites and clays: Clinoptilolite, bentonite and kaolin
No full textIn this study, adsorption of salicylic acid, acetylsalicylic acid and atenolol from aqueous solutions onto clinoptilolite modified with sorbed metallic cations (Cu(II), Zn(II), Ni(II) or Mn(II)) have been probed. Natural clays (kaolin and bentonite, pure or ion-exchanged by octadecyl dimethyl benzyl ammonium chloride) have been also probed as adsorbents. The adsorption was studied at 30 degrees C by titration microcalorimetry, employed to obtain the heats evolved as a result of adsorption. Adsorption experiments were performed under the same conditions, the equilibrium adsorbate concentrations were determined by fluorescence spectrophotometry. The maximal adsorption capacities of investigated solids against target pharmaceuticals lie in the range of 10(-5)-10(-6) mol/g. Modified minerals have shown different capacities in comparison with natural ones. The adsorption capacities are dependent on the characteristics of pharmaceutically active compound. The results obtained in this work show that natural materials can be used effectively in the removal of investigated pharmaceuticals by adsorption
Influence of pH value on cu(II) biosorption by lignocellulose peach shell waste material
No full textJedan od glavnih faktora u procesu biosorpcije predstavlja pH vrednost rastvora sorbata, jer istovremeno utiče na hemijsko ponašanje prisutnih kontaminanata kao i na aktivnost funkcionalnih grupa biosorbenta. U ovom radu ispitan je uticaj pH vrednosti u procesu biosorpcije dvovalentnog bakra, nemodifikovanom otpadnom lignoceluloznom masom koštica breskve (KB). Procenat uklanjanja bakra ovim biosorbentom znatno varira u ispitivanom opsegu pH vrednosti, počev od 2,62% za pH vrednost 2, do 90,43% za pH vrednost 6, pri inicijalnoj koncentraciji bakra od 50 mg/l. Rezultati ispitivanja pokazali su da je za KB pri izabranim operativnim uslovima, proces neophodno voditi na pH 5, što je vrednost nešto viša od vrednosti nultog naelektrisanja (pHpzc) koja iznosi 4,75±0,1. Potvrđena je neophod-nost održavanja pH vrednosti konstantnom za vreme procesa, pri čemu je biosorpcioni kapacitet KB dvostruko veći od biosorpcionog kapaciteta bez održavanja pH vrednosti.In the last decade, pollution from anthropogenic sources has reached high levels. Special attention is being paid to heavy metals because of their high toxicity, persistence and bioaccumulation tendency. Since the conventional methods for their removal are either too expensive or create large quantities of toxic sludge, attention has been turning to new technologies such as biosorption, technology that use cheap, abundant, organic waste for sequestering pollutants from contaminated mediums. Among the other factors that affect biosorption process, pH value is one of the most important because it directs both the metal solution chemistry as well as the activity of the biomass functional groups. In this paper, the influence of pH value on biosorption of Cu (II) by unmodified low-cost lignocellulose biosorbent - peach shell (PS) particles, has been studied. The chemical composition of PS, point of zero charge (pHPZC), as well as its surface morphology is also presented. The results showed that this biosorbent contains mainly cellulose and lignin, the components that carry the functional groups responsible for metal binding. Its multilayer surface contains many pores and channels that help diffusion in deeper layers and force biosorption process. Point of zero charge determination was performed with three different KNO3 ionic strengths: 0.1, 0.01 and 0.001 M. The obtained value for pHPZC was 4.75±0.1 and showed that this biosorbent is non-sensitive to the ionic strength of the electrolyte applied. Biosorption experiments were done with peach shell particles of diameters 0.5+0.1 mm at 25°C. The initial copper (II) concentration was 50 mg/dm3 while the biosorbent concentration was 10 g/dm3. Experiments were performed with and without keeping the pH constant. The influence of pH on biosorption process was examined in a pH range of 2-6. The percentage of Cu (II) removed by PS reached its maximum at pH 6, with 90.43% removal, but this percentage can also be attributed to the precipitation of metal at this pH value. However, under the same operational conditions, but at pH 2, the retention of copper was equal to 2.62%. The results also indicate that it is necessary to lead the biosorption process with keeping the pH constant at all times, since the copper removal was about 46% less when the pH value was not kept constant during the biosorption process. The pH value obtained as optimal was slightly higher than the pHPZC value, which indicates that electrostatic attraction is one of the possible binding mechanisms in biosorption process. The results have showed that the removal of Cu (II) with peach shell particles is very sensitive to solution pH and that this parameter should be thoroughly investigated and strongly controlled during the whole removal process