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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Karakterizacija bioremedijacionih procesa u sedimentima zagađenim policikličnim aromatičnim ugljovodonicima i procena biodostupnosti / Characterisation of bioremediation processes in sediment contaminated with polycyclic aromatic hydrocarbons and bioavailability assessment

Beljin Jelena 17 December 2015 (has links)
<p>U okviru ovog istraživanja ispitani su: 1. Optimalni uslovi&nbsp; za<br />eksperimente biodegradacije policikličnih aromatičnih ugljovodonika sa istim i<br />različitim brojem prstenova; 2. Uticaj struture&nbsp; i matriksa na biodegradaciju<br />policikličnih aromatičnih ugljovodonika sa istim brojem prstenova; 3.<br />Fitotoksičnost biljaka&nbsp; (testovi klijavosti i usvajanje policikličnih aromatičnih<br />ugljovodonika); 4. Procena&nbsp; potencijalne&nbsp; biodostupne frakcije primenom<br />različitih hemijskih sorbenata (HPCD, &beta;CD&nbsp; i&nbsp; MCD, XAD4 i TenaxTA)&nbsp; i 5.<br />Korelacija dobijenih rezultata&nbsp; testovima biodegradacije, testovima klijavosti,<br />testovima fitotoksičnosti i rezultata dobijenih iz eksperimenta procene<br />biodostupnosti hemijskim testovima.&nbsp; Rezultati su pokazali da se&nbsp; optimalni<br />uslovi za biodegradaciju&nbsp; postižu dodatkom mineralnih medijuma, inokuluma i<br />surfaktanata.&nbsp; Posmatrajući uticaj sadržaja gline i organske materije i strukture<br />molekula,&nbsp; najveći stepen biorazgradnje ima fluoranten, &scaron;to je u skladu sa<br />njegovim fizičko-hemijskim osobinama, dok se sadržaj pirena i krizena nije<br />mogao jasno korelirati sa sadržajem organske materije i gline.&nbsp; &Scaron;to se tiče<br />testova fitotoksičnosti,&nbsp; sva semena su proklijala, &scaron;to govori u prilog tome&nbsp; da<br />me&scaron;avina ovih kontaminanata&nbsp; pri ispitivanim koncentracijama&nbsp; nije inhibirala<br />klijanje biljaka.&nbsp; Testovi usvojivosti ispitivanih PAH-ova su pokazali da je<br />najmanji procenat usvojivosti semenom dobijen za benzo(a)piren, &scaron;to se može<br />objasniti njegovom kompleksnijom strukturom. Hemijskim testovima za<br />procenu biodostupnosti je sa druge strane pokazano da se desorpcija u prisustvu<br />MCD, XAD4 smole i Tenaxa može koristiti kao jednostavna metoda za procenu<br />potencijalne biodostupne&nbsp; frakcije organskih jedinjenja u sistemima sediment&nbsp; -voda.</p> / <p>The aim of this study was to investigate: 1. The optimal conditions for&nbsp;the biodegradation of polycyclic aromatic hydrocarbons with the same and&nbsp;different numbers of rings; 2. The impact of structure and matrix&nbsp;biodegradation of polycyclic aromatic hydrocarbons with the same number of&nbsp;rings; 3. Phytotoxicity (germination tests and polycyclic aromatic hydrocarbon&nbsp;uptake); 4. The means for assessing the bioavailable fractions using various&nbsp;chemical sorbents (HPCD, &beta;CD, MCD, XAD4 and &nbsp;TenaxTA) and 5. The&nbsp;correlation between the results of the biodegradation tests, germination tests,&nbsp;phytotoxicity tests and the results obtained from the experiments in the&nbsp;assessment of bioavailability and chemical tests. The results showed that the&nbsp;optimal conditions for biodegradation are achieved by the addition of mineral&nbsp;media, inoculum and surfactants. When considering the effect of the contents of&nbsp;clay and organic matter and the structure of the molecules, the highest degree of&nbsp;biodegradation was observed with fluoranthene,&nbsp; which is in line with its&nbsp;physico-chemical properties. The concentrations of pyrene and chrysene were&nbsp;not clearly correlated with the organic matter and clay contents. During thephytotoxicity tests, all seeds sprouted, which speaks in favor of a mixture of&nbsp;these contaminants not inhibiting the germination of the plants. Tests for the&nbsp;uptake of the investigated PAHs showed that the lowest percentage seed uptake&nbsp;was for benzo(a)pyrene, which is explained by its more complex structure.&nbsp;Chemical tests for evaluating bioavailability have shown that desorption in the&nbsp;presence of MCD, XAD4 and Tenax resins can be used as a simple method for&nbsp;the evaluation of a potential bioavailable fraction of organic compounds in&nbsp;water-sediment systems.</p>
2

Analiza korelacije mehanizama rasprostiranja i koncentracionih nivoa pesticida u podzemnoj vodi / Correlation analysis of transport mechanisms and concentration levels ofpesticides in groundwater

Živančev Nevena 30 September 2019 (has links)
<p>Osnovni cilj teze bio je doprinos poznavanju prisustva pesticida u površinskim i podzemnim vodama u Srbiji, kao i mehanizama rasprostiranja podzemnom vodom. Korišćeni su rezultati sedmogodišnje kampanje analize kvaliteta površinske vode i korespodentnih punktova za zahvatanje podzemne vode za četiri velike reke u Srbiji: Dunav, Savu, Tisu i Veliku Moravu. Pored sistematizacije i analize podataka o izvršenim analizama na pesticide voda reka i podzemnih voda, urađena su usmerena istraživanja koja se odnose na mehanizme i intenzitet sorbiranja, laboratorijska ispitivanja i terenski ogled. Rezultati ispitivanja i analiza su obrađeni numeričkim modelima.</p> / <p>The main aim of the thesis was to contribute to the knowledge of the presence<br />of pesticides in surface and groundwaters in Serbia, as well as transport<br />mechanisms in groundwater. The results of a seven-year analysis of the<br />quality of surface waters and correspondent points for groundwater<br />abstraction for the four major rivers in Serbia were used: Danube, Sava, Tisa<br />and Velika Morava. In addition to systematization and analysis of data from<br />campaigns carried out for the presence of pesticides in river water and<br />groundwater, targeted research related to the mechanisms and intensity of<br />sorption was implemented that consisted of laboratory and field experiment.<br />The results of experiments and analyzes were processed by numerical<br />models.</p>
3

Primena sorpcionih parametara odabranih hidrofobnih organskih polutanata na organskoj materiji sedimenata za procenu njihove dostupnosti u sistemima sediment-voda / Application of the parameters ofsorption of selected hydrophobic organic compounds onto the sediment organic matter for the assessment of their availability in the sediment-water system

Tričković Jelena 25 May 2009 (has links)
<p>Prirodna organska materija zemlji&scaron;ta/sedimenata predstavlja glavnu oblast<br />za sorpciju hidrofobnih organskih jedinjenja, a njene osobine utiču na stepen<br />retencije i konsekventnu (bio)dostupnost organskih jedinjenja. Da bi se procenio<br />ekotoksikolo&scaron;ki rizik zagađenih zemlji&scaron;ta/sedimenata po okolinu, dizajnirala<br />odgovarajuća strategija remedijacije ili predvidela sudbina i transport organskih<br />polutanata u zagađenim zonama, neophodno je razumevanje mehanizma sorpcije i<br />desorpcije na nivou mehanizma uspostavljenih veza. U radu je izvr&scaron;eno ispitivanje<br />sorpcije i desorpcije odabranih hidrofobnih organskih polutanata, pentahlorbenzena<br />i lindana, na sekvencijalno ekstrahovanim huminskim kiselinama i huminima iz<br />jednog uzorka sedimenta u cilju pronalaženja veze između strukturnih<br />karakteristika izolovanih huminskih kiselina i humina i sorpcionih i desorpcionih<br />parametara. Afinitet za sorpciju, nelinearnost izotermi i prividna sorpciono-desorpciona histereza korelirani su&nbsp; sa osobinama sorbenata dobijenim iz<br />elementarne i FTIR spektroskopske analize. Predloženo je da je mehanizam<br />sorpcije na huminskim kiselinama rezultat odigravanja raspodele i specifične<br />adsorpcije, pri čemu se pri nižim koncentracijama pentahlorbenzena i lindana prvo<br />popune sorpciona mesta u kondenzovanoj aromatičnoj oblasti, a tek potom pri<br />vi&scaron;im koncentracijama sorpciona mesta u amorfnim alifatičnim oblastima.<br />Sveukupno vi&scaron;i koeficijenti nelinearnosti dobijeni za sorpciju pentahlorbenzena na huminskim kiselinama u odnosu na nelinearnost sorpcionih izotermi lindana, ukazuju na to da u ukupnoj sorpciji pentahlorbenzena veći značaj ima mehanizam raspodele i sme&scaron;tanje molekula pentahlorbenzena u hidrofobne &scaron;upljine huminskih kiselina, u odnosu na specifičnu adsorpciju. Ovi zaključci su potvrđeni rezultatima spektroskopskih istraživanja interakcija&nbsp; odabranih organskih jedinjenja i N-metilformamida. Predloženi mehanizam sorpcije ne može objasniti sorpciju pentahlorbenzena i lindana na uzorcima humina, većje pretpostavljeno da nelinearna sorpcija za uzorke humina može biti rezultat ostvarivanja povr&scaron;inskih interakcija, a visoki afinitet za sorpciju rezultat je raspodele organskih jedinjenja u amorfnim alifatičnim oblastima koje pružaju odlično okruženje za sorpciju.</p><p>U cilju daljeg proučavanja mehanizma sorpcije, izvr&scaron;eno je ispitivanje kinetike<br />desorpcije tri odabrana hidrofobna organskajedinjenja, pentahlorbenzena, lindana i<br />pentahloranilina, posredstvom&nbsp; čvrstog adsorbenta, XAD-4 makroporozne<br />jonoizmenjivačke smole. Na osnovu rezultata dobijenih za uzorak sedimenta i<br />frakciju &lt; 125 &micro;m za dva ravnotežna vremena (15 i 90 dana) i za sva odabrana<br />organska jedinjenja može se zaključiti da se za procenu potencijalne (bio)dostupne<br />frakcije organskih jedinjenja može koristiti jednostavna desorpcija u prisustvu<br />XAD-4 makroporozne jonoizmenjivačke smole i to na dva načina: (1) ekstrakcijom<br />sedimenta tokom 24 časa, kada frakcija koja se desorbuje odgovara frakciji<br />jedinjenja koja se nalazi u brzo-desorbujućem domenu organske materije, ili (2)<br />ekstrakcijom tokom 6 časova, kada frakcija koja se desorbuje odgovara polovini<br />one frakcije jedinjenja koja se nalazi u brzo-desorbujućem domenu organske<br />materije.</p> / <p>Natural organic matter of soil/sediment make the main region for&nbsp;sorption of hydrophobic organic compounds, ant its properties influence the degree&nbsp;of retention and, consequently, (bio)availability of organic compounds. In order to&nbsp;assess the ecotoxicological risks of contaminated soils/sediments to the&nbsp;environment and design the appropriate remediation strategy or predict the fate and&nbsp;transport of organic pollutants in contaminated zones, it is necessary to understand&nbsp;the mechanisms of sorption/desorption at the level of the mechanism of established&nbsp;bonds. Study of the sorption and desorption of selected hydrophobic organic&nbsp;pollutants, pentachlorobenzene and lindane, on sequentially extracted humic acids&nbsp;and humins from a single sediment sample with the aim of finding the relationship&nbsp;between the structural characteristics of the isolated humic acids and humin and&nbsp;sorption and desorption parameters. Sorption affinity, nonlinearity of isotherms,&nbsp;and apparent sorption-desorption hysteresis were correlated to the sorbent&nbsp;characteristics obtained from elemental analysis and FTIR spectroscopic data. The&nbsp;proposed sorption mechanism on humic acids assumes that at low concentrations&nbsp;of pentachlorobenzene and lindane the sorption sites in the condensed aromatic&nbsp;region are occupied first, and then, at their higher concentrations, the sorption sites&nbsp;in the amorphous and aliphatic regions. Generally higher nonlinearity coefficient obtained for the sorption of pentachlorobenzene on &nbsp;umic acids compared with the nonlinearity of sorption isotherms for lindane, indicate that in the overall sorption of pentachlorobenzene of higher significance is the &nbsp;echanism of distribution and insertion of pentachlorobenzene molecule into hydrophobic dips of humic acids, compared to specific adsorption. These conclusions were confirmed with the results of spectroscopic investigation of &nbsp;intermolecular interaction of chosen organic compounds and N-methylformamide.Since suggested sorption mechanism could not explain sorption of &nbsp;pentachlorobenzene and lindane onto humin samples, it is supposed that the nonlinearity can be a result of surface interactions, while the high sorption affinity is result of distribution of organic compounds in the amorphous aliphatic regions that offer an excellent environment for sorption.</p><p>With the aim of further insight into the sorption mechanism, investigation of&nbsp;desorption kinetics of three chosen hydrophobic organic compounds,&nbsp;pentachlorobenzene, lindane and pentachloroaniline, in the presence of &nbsp;soild&nbsp;adsorbent XAD-4 macroporous ion-exchange resin was performed. On the basis of&nbsp;the results obtained for sediment sample and fraction &lt; 125 &micro;m at two equilibrium&nbsp;times (15 and 90 days) and for all selected organic compounds, it can be concluded&nbsp;that the assessment of the potential (bio)avialable fraction of organic compounds&nbsp;may be obtained by using simple method of desorption in the presence of XAD-4&nbsp;macroporous ion-exchange resin, performed in two ways: (1) by sediment&nbsp;<br />extraction during 24 hours, when the desorbing fraction corresponds to the fraction&nbsp;of &nbsp;he compound that is found in the fast-desorbing domain of organic matter, or&nbsp;(2) by 6-hour extraction, when the desorbing fraction corresponds to one half of the&nbsp;fraction appearing in the fast-desorbing domain of the organic matter.</p>
4

Procena remedijacionog potencijala sedimenta zagađenog prioritetnim organskim zagađujućim materijama / Investigation of remediation potential of sediment polluted with priority organic pollutants

Grgić Marko 16 August 2019 (has links)
<p>Predmet&nbsp; istraživanja&nbsp; ove&nbsp; doktorske&nbsp; disertacije&nbsp; je&nbsp; procena&nbsp; potencijalno&nbsp; biodostupne&nbsp; frakcije odabranih&nbsp; prioritetnih&nbsp; organskih&nbsp; polutanata&nbsp;&nbsp; (pentahlorbenzena,&nbsp; heksahlorbenzena,&nbsp; lindana, trifluralina, 4-oktilfenola i 4-nonilfenola) u sedimentu, ispitivanje biodegradacionog potencijala ovih&nbsp; jedinjenja&nbsp; u&nbsp; sedimentu&nbsp; u&nbsp; različitim&nbsp; uslovima,&nbsp; kao&nbsp; i&nbsp; procena&nbsp; potencijala&nbsp; stabilizacije<br />sedimenta&nbsp; dodatkom&nbsp; ugljeničnih&nbsp; sorpcionih&nbsp; agenasa.&nbsp; U&nbsp; cilju&nbsp; razvoja&nbsp; metoda&nbsp; za&nbsp; određivanje biodostupnosti odabranih organskih polutanata ispitivane su i&nbsp; optimizovane metode vi&scaron;estepene i jednostepene parcijalne ekstrakcije primenom sledećih hemijskih agenasa:&nbsp; Tenaks&nbsp; smole, XAD-4&nbsp; smole&nbsp; i&nbsp; rastvora&nbsp; ciklodekstrina&nbsp; (2-hidroksipropil-&beta;-ciklodekstrina,&nbsp; &beta;-ciklodekstrina&nbsp; i&nbsp; metil-&beta;-ciklodekstrina).&nbsp; Optimalni&nbsp; agens&nbsp; za&nbsp; procenu&nbsp; biodostupne&nbsp; frakcije&nbsp; odabranih&nbsp; organskih zagađujućih&nbsp; materija&nbsp; sa&nbsp; sedimenta&nbsp; XAD-4&nbsp; smola,&nbsp; a&nbsp; optimalno&nbsp; vreme&nbsp; ekstrakcije&nbsp; primenom jednostepenih&nbsp; ekstrakcija&nbsp; je&nbsp; oko&nbsp; 8&nbsp; h.&nbsp; Procena&nbsp; biodegradacionog&nbsp; potencijala&nbsp; odabranih prioritetnih&nbsp; organskih&nbsp; zagađujućih&nbsp; materija&nbsp; u&nbsp; sedimentu&nbsp; ispitana&nbsp; je&nbsp; u&nbsp; različitim&nbsp; aerobnim&nbsp; i anaerobnim uslovima uz optimizaciju uslova putem biostimulacije i bioaugmentacije. Pokazano je&nbsp; da&nbsp; svih&nbsp; &scaron;est&nbsp; odabranih&nbsp; jedinjenja&nbsp; poseduju&nbsp; značajan&nbsp; potencijal&nbsp; biodegradacije&nbsp; u&nbsp; anaerobnoj sredini&nbsp; pri&nbsp; čemu&nbsp; u&nbsp; slučaju&nbsp; lindana&nbsp; i&nbsp; trifluralina&nbsp; dolazi&nbsp; do&nbsp; potpunog&nbsp; uklanjanja&nbsp; biodostupne količine&nbsp; jedinjenja&nbsp; primenom&nbsp; sva&nbsp; četiri&nbsp; ispitana&nbsp; inokuluma.&nbsp; Aerobni&nbsp; potencijal&nbsp; u&nbsp; ispitanim uslovima&nbsp; pokazali&nbsp; su&nbsp; samo&nbsp; alkil&nbsp; fenoli,&nbsp; gde&nbsp; je&nbsp; takođe&nbsp; uklonjena&nbsp; skoro&nbsp; celokupna&nbsp; količinabiodostupne&nbsp; frakcije&nbsp; jedinjenja&nbsp; u&nbsp; sedimentu&nbsp; (78-85%).&nbsp; Potencijal&nbsp; remedijacije&nbsp; sedimenta dodatkom&nbsp; ugljeničnih&nbsp; materijala&nbsp; ispitan&nbsp; je&nbsp; sa&nbsp; aspekta&nbsp; odabira&nbsp; ugljeničnih&nbsp; sorpcionih&nbsp; agenasa (aktivni&nbsp; ugalj,&nbsp; biougalj&nbsp; i&nbsp; humus);&nbsp; određivanja&nbsp; optimalne&nbsp; količine&nbsp; materijala;&nbsp; isptivanja dugoročnih i kratkoročnih efekata dodatka ovih agenasa na biodostupnost organskih zagađujućih materija&nbsp; kako&nbsp; bi&nbsp; se&nbsp; ispitao&nbsp; efekat&nbsp; starenja &nbsp; i&nbsp; toksičnosti&nbsp; dobijenih&nbsp; sme&scaron;a.&nbsp; Rezultati&nbsp; stabilizacije zagađujućih&nbsp; supstanci&nbsp; u&nbsp; sedimentu&nbsp; pokazuju&nbsp; da:&nbsp; (1)&nbsp; povećanje&nbsp; doze&nbsp; sva&nbsp; tri&nbsp; sorpciona&nbsp; agensa dovodi&nbsp; do&nbsp; povećanja&nbsp; efikasnosti&nbsp; imobilizacije&nbsp; i&nbsp; smanjenja&nbsp; biodostupne&nbsp; frakcije&nbsp; odabranih organskih jedinjenja; (2) starenjem sme&scaron;a sedimenta i&nbsp; sorbenata u toku prvih 90 dana dolazi do daljeg smanjenja biodostupne frakcije svih jedinjenja, nakon čega se biodostupna koncentracija ispitivanih&nbsp; jedinjenja&nbsp; primenom&nbsp; aktivnog&nbsp; uglja&nbsp; ne&nbsp; menja,&nbsp; dok&nbsp; primenom&nbsp; biouglja&nbsp; i&nbsp; humusa&nbsp; dolazi&nbsp; do&nbsp; porasta&nbsp; biodostupne&nbsp; frakcije&nbsp; jedinjenja.&nbsp; Testovi&nbsp; fitotoksičnosti&nbsp; su&nbsp; pokazali&nbsp; da&nbsp; je&nbsp; <em>Zea mays&nbsp; </em>akumulirao&nbsp; značajno&nbsp; veće&nbsp; količine&nbsp; ispitivanih&nbsp; jedinjenja&nbsp; iz&nbsp; netretiranog&nbsp; sedimenta&nbsp; u poređenju sa&nbsp; <em>Cucurbita pepo</em>&nbsp; i&nbsp;<em> Lactuca sativa. </em>Toksičnost sme&scaron;a sedimenta sa aktivnim ugljom i humusom&nbsp; procenjena&nbsp; na&nbsp; osnovu&nbsp; inhibicije&nbsp; luminiscencije&nbsp; na&nbsp; <em>Vibrio&nbsp; fischeri</em>&nbsp; kao&nbsp; i&nbsp; ispitivanjem <em>Zea&nbsp; mays&nbsp; </em>germinacije&nbsp; i&nbsp; produkcije&nbsp; biomase&nbsp; je&nbsp; pokazala&nbsp; značajno&nbsp; smanjenje&nbsp; u&nbsp; odnosu&nbsp; na netretirani&nbsp; sediment.&nbsp; Akumulacija&nbsp; ispitivanih&nbsp; jedinjenja&nbsp; u&nbsp; biomasi&nbsp; <em>Zea&nbsp; mays&nbsp; </em>u&nbsp; netretiranom sedimentu je bila značajno veća u odnosu na sve sme&scaron;e sedimenta i aktivnog uglja i humusa. Sva tri&nbsp; sorbenta&nbsp; pokazala&nbsp; su&nbsp; veliki&nbsp; remedijacioni&nbsp; potencijal&nbsp; za&nbsp; sediment&nbsp; zagađen&nbsp; organskim zagađujućim supstancama, ali je aktivni ugalj pokazao najbolje performance.</p> / <p>The&nbsp; aim&nbsp; of&nbsp; the&nbsp; research&nbsp; in&nbsp; this&nbsp; PhD&nbsp; dissertation&nbsp; is&nbsp; the&nbsp; assessment&nbsp; of&nbsp; the&nbsp; potentially biodegradable&nbsp; fraction&nbsp; of&nbsp; selected&nbsp; organic&nbsp; pollutants&nbsp;&nbsp; (pentachlorbenzene,&nbsp; hexachlorobenzene, lindane,&nbsp; trifluraline,&nbsp; 4-octylphenol&nbsp; and&nbsp;&nbsp;&nbsp; 4-nonylphenol)&nbsp; in&nbsp; the&nbsp; sediment,&nbsp; estimation&nbsp; of&nbsp; the biodegradation potential of these compounds in sediment in different conditions, as well as the assessment&nbsp; of&nbsp; the&nbsp; stabilization&nbsp; potential&nbsp; sediment&nbsp; by&nbsp; the&nbsp; sediment&nbsp; amendment&nbsp; with&nbsp; of&nbsp; carbon rich sorption agents. In order to develop and optimise&nbsp; methods for the bioavailability assessment of&nbsp; the&nbsp; selected&nbsp; organic&nbsp; pollutants,&nbsp; methods&nbsp; of&nbsp; multistage&nbsp; and&nbsp; single-step&nbsp; non&nbsp; exhaustive extraction&nbsp; were&nbsp; studied&nbsp; using&nbsp; the&nbsp; following&nbsp; chemical&nbsp; agents:&nbsp; Tenax&nbsp; resin,&nbsp; XAD -4&nbsp; resin&nbsp; and&nbsp; a cyclodextrin&nbsp; solution&nbsp; (2-hydroxypropyl- &beta;-cyclodextrin,&nbsp; &beta;-cyclodextrin&nbsp; and&nbsp; methyl-&beta;-cyclodextrin).&nbsp; Results&nbsp; showed&nbsp; that&nbsp; optimal&nbsp; agent&nbsp; for&nbsp; estimating&nbsp; the&nbsp; bioavailable&nbsp; fraction&nbsp; of selected organic pollutants from the sediment is XAD-4 resins, and that the optimum extraction time using single-step extraction is about 8 h. The assessment of the biodegradation potential of selected&nbsp; priority&nbsp; organic&nbsp; pollutants&nbsp; in&nbsp; the&nbsp; sediment&nbsp; was&nbsp; examined&nbsp; in&nbsp;&nbsp; various&nbsp; aerobic&nbsp; and anaerobic&nbsp; conditions,&nbsp; with&nbsp; the&nbsp; optimization&nbsp; of&nbsp; conditions&nbsp; through&nbsp; biostimulation&nbsp; and bioaugmentation.&nbsp; It&nbsp; has&nbsp; been&nbsp; shown&nbsp; that&nbsp; all&nbsp; six&nbsp; selected&nbsp; compounds&nbsp; possess&nbsp; significant biodegradation&nbsp; potential&nbsp; in&nbsp; the&nbsp; anaerobic&nbsp; environment,&nbsp; where&nbsp; in&nbsp; the&nbsp; case&nbsp; of&nbsp; lindane&nbsp; and trifluraline there is complete removal of the bioavailable amount of the compound&nbsp;&nbsp; using all four inoculum tested. Aerobic potential under the applied conditions has been showen only for alkyl phenols,&nbsp; where&nbsp; almost&nbsp; all&nbsp; of&nbsp; the&nbsp; bioavailable&nbsp; fraction&nbsp; of&nbsp; the&nbsp; compound&nbsp; in&nbsp; the&nbsp; sediment&nbsp; was removed (78-85%). The potential of sediment remediation with the amendment of sediment withcarbon&nbsp; rich&nbsp; materials&nbsp; was&nbsp;&nbsp; examined&nbsp; from&nbsp; the&nbsp; aspect&nbsp; of&nbsp; selecting&nbsp; carbon&nbsp; sorption&nbsp; agents (activated carbon, biochar and humus); estimation the optimal material doses; the long -term and short-term effects of the addition&nbsp; of these agents on the bioavailability of organic pollutants&nbsp; in order to examine the effect of aging and the toxicity of the resulting mixtures. The results of the stabilization of pollutants in the sediment show that: (1)&nbsp; increasing the dose of all three&nbsp;&nbsp; sorption agents&nbsp; leads&nbsp; to&nbsp; an&nbsp; increase&nbsp; in&nbsp; the&nbsp; immobilization&nbsp; efficiency&nbsp; and&nbsp; reduction&nbsp; of&nbsp; the&nbsp; bioavailable fraction of the selected&nbsp; organic compounds; (2) aging of the amended sediment during the first 90 days results in a further reduction of the biodegradable fraction of all compounds, after which the&nbsp; biodegradable&nbsp; concentration&nbsp; of&nbsp; the&nbsp; selected&nbsp; compounds&nbsp; remain&nbsp; the&nbsp; same&nbsp; in&nbsp; the&nbsp; case&nbsp; of activated carbon amendment, while the bioavailable fraction of&nbsp; the compound increases with the use&nbsp; of&nbsp; biohar&nbsp; and&nbsp; humus.&nbsp; Phytotoxicity&nbsp; tests&nbsp; showed&nbsp; that&nbsp; <em>Zea&nbsp; mays&nbsp;</em> accumulated&nbsp; significantly higher amount of selected organic pollutants from unamended sediment, comparing to&nbsp; <em>Cucurbita pepo&nbsp;</em> and <em>Lactuca sativa</em>. Toxicity of activated carbon and humus amended sediment assessed by <em>Vibrio&nbsp; fischeri&nbsp;</em> luminescence&nbsp; inhibition&nbsp; test&nbsp; and&nbsp; by&nbsp; measuring&nbsp; <em>Zea&nbsp; mays&nbsp; </em>germination&nbsp; and biomass yield was significantly reduced in the amended sediment samples. Accumulation of the selected&nbsp; organic&nbsp; pollutants&nbsp; in&nbsp; the&nbsp; <em>Zea&nbsp; mays</em>&nbsp; biomass&nbsp; in&nbsp; the&nbsp; unamended&nbsp; sediment&nbsp; were&nbsp; a significantly&nbsp; higher&nbsp; than&nbsp; in&nbsp; the&nbsp; humus&nbsp; and&nbsp; activated&nbsp; carbon&nbsp; amended&nbsp; sediment.&nbsp; Both&nbsp; sorbents show&nbsp; potential&nbsp; to&nbsp; be&nbsp; used&nbsp; as&nbsp; remediation&nbsp; agents&nbsp; for&nbsp; organically&nbsp; contaminated&nbsp; sediment,&nbsp; but activated carbon exhibited the better performance.</p>
5

Sinteza, karakterizacija i primena sorbenata na bazi gvožđa i mangana za uklanjanje arsena iz vode / Synthesis, characterisation and application iron and manganeous based sorbents for arsenic removal from water

Nikić Jasmina 12 July 2019 (has links)
<p>Prisusutvo&nbsp; arsena&nbsp; u&nbsp; podzemnim&nbsp; vodama,&nbsp; koje&nbsp; se&nbsp; primenjuju&nbsp; za vodosnabdevanje stanovni&scaron;tva je globalan problem. Različiti&nbsp; konvencionalni<br />procesi&nbsp; se primenjuju&nbsp; za&nbsp; uklanjanje&nbsp; arsena iz vode, uključujući koagulaciju i<br />flokulaciju,&nbsp; sorpciju,&nbsp; membransku&nbsp; filtraciju&nbsp; i&nbsp; jonsku&nbsp; izmenu.&nbsp; Uzimajući&nbsp; u<br />obzir relativnu nisku cenu, jednostavnu kontrolu procesa i održavanje, visok<br />stepen uklanjanja arsena, sorpcija se smatra jednom od najpodobnijih tehnika<br />za uklanjanje arsena u tretmanu vode za piće. Premda su na trži&scaron;tu dostupni<br />različiti&nbsp; sorbenti&nbsp; za&nbsp; uklanjanje&nbsp; arsena,&nbsp; postoji&nbsp; potreba&nbsp; za&nbsp; iznalaženjem&nbsp; i<br />razvojem&nbsp; novih&nbsp;<em> low-cost&nbsp;</em> sorbenata,&nbsp; a&nbsp; kojima&nbsp; bi&nbsp; se&nbsp; pak&nbsp; mogao&nbsp; obezbediti<br />visok stepen uklanjanja oba oksidaciona oblika&nbsp; arsena,&nbsp; i&nbsp; As(III) i As(V). Cilj<br />ovog rada bio je usmeren na sintezu i karakterizaciju novih sorbenata na bazi<br />gvožđa&nbsp; i&nbsp; mangana&nbsp; odnosno&nbsp; Fe-Mn&nbsp; binarnog&nbsp; oksida,&nbsp; ispitivanje&nbsp; njihovog<br />potencijala&nbsp; za&nbsp; uklanjanje&nbsp; arsena&nbsp; iz&nbsp; vode&nbsp; i&nbsp; utvrđivanje&nbsp; da&nbsp; li&nbsp; novosintetisani<br />sorbenti po pitanju efikasnosti, mogu konkurisati postojećim komercijalnim i<br />&scaron;iroko kori&scaron;ćenim sorbentima u tretmanima voda.<br />Metodom&nbsp; precipitacije,&nbsp; sintetisani&nbsp; su&nbsp; Fe-Mn&nbsp; binarni&nbsp; oksidi&nbsp; sa&nbsp; različitim Fe:Mn&nbsp; molskim&nbsp; odnosima&nbsp; 1:1,&nbsp; 3:1,&nbsp; 6:1&nbsp; i&nbsp; 9:1,&nbsp; dok&nbsp; su&nbsp; kombinacijom heterogene&nbsp; nukleacione&nbsp; tehnike&nbsp; i&nbsp; precipitacije,&nbsp; sintetisana&nbsp; i&nbsp; četiri&nbsp; sorbenta magnetnih&nbsp; svojstava&nbsp; (Mag,&nbsp; Mag-Fe,&nbsp; Mag-Mn,&nbsp; Mag-FeMn).&nbsp; Modifikacijom biopolimera&nbsp; Chitosana&nbsp; i&nbsp; GAC,&nbsp; sa&nbsp; Fe-Mn&nbsp; binarnim&nbsp; oksidom,&nbsp; razvijena&nbsp; su preostala&nbsp; dva&nbsp; materijala&nbsp; Chit-FeMn,&nbsp; odnosno&nbsp; GAC-FeMn.&nbsp; Sintetisani sorbenti su karakterisani različitim tehnikama i metodama (SEM/EDS, XRD,FTIR, BET).Fizičko-hemijskom karakterizacijom sintetisanih sorbenata ustanovljeno je da se Fe-Mn binarni oksidi i magnetni materijali, karakteri&scaron;u relativno velikim specifičnim&nbsp; povr&scaron;inama&nbsp; (109-300&nbsp; m<sup> 2 </sup>/g)&nbsp; i&nbsp; zapreminama&nbsp; mezopora (0,144-0,403&nbsp; cm <sup>3</sup> /g).&nbsp; Velika&nbsp; specifična&nbsp; povr&scaron;ina&nbsp; i&nbsp; razvijena&nbsp; mikroporozna struktura uočena je kod GAC-FeMn (996 m<br /><sup>2</sup> /g; 0,394 cm<sup> 3 /</sup>g). U poređenju sa ostalim&nbsp; sintetisanim&nbsp; sorbentima,&nbsp; Chit-FeMn&nbsp; je&nbsp; karakterisala&nbsp; najmanja specifična&nbsp; povr&scaron;ina&nbsp; i&nbsp; zapremina&nbsp; mezopora&nbsp; (1,99&nbsp; m<br /><sup>2 </sup>/g;&nbsp; 0,014&nbsp; cm <sup>3</sup> /g).&nbsp; XRD analiza&nbsp; Fe-Mn&nbsp; binarnih&nbsp; oksida&nbsp; ukazala&nbsp; je&nbsp; da&nbsp; je&nbsp; fazna&nbsp; struktura&nbsp; sintetisanih Fe-Mn&nbsp; binarnih&nbsp; oksida&nbsp; slična&nbsp; ferihidratu&nbsp; dok&nbsp; je&nbsp; fazna&nbsp; struktura&nbsp; magnetnih materijala ukazala na prisustvo magemita.<br />Ispitivanja kinetike sorpcionog procesa ukazala su da je mehanizam sorpcije<br />As(III)&nbsp; i&nbsp; As(V)&nbsp; na&nbsp; sintetisanim&nbsp; sorbentima&nbsp; sloţena&nbsp; kombinacija&nbsp; povr&scaron;inske<br />hemisorpcije,&nbsp; koja&nbsp; se&nbsp; odvija&nbsp; kroz&nbsp; granični&nbsp; sloj&nbsp; čestica&nbsp; sorbenata&nbsp; i unutarčestične difuzije. Tome u prilog i&scaron;li su i rezultati FTIR analize kojima<br />je potvrđeno da se sorpcija arsena na sintetisanim sorbentima ostvaruje kroz<br />interakcije hidroksilnih grupa gvožđa prisutnih na povr&scaron;ini sorbenata i arsena.<br />Dodatno, pokazano je da se za razliku od sorpcije As(V), sorpcija As(III) na sorbentima&nbsp; koji&nbsp; pored&nbsp; oksida&nbsp; gvožđa&nbsp; sadrže&nbsp; i&nbsp; okside&nbsp; mangana&nbsp; (Fe-Mn binarni oksidi, Mag-FeMn, Mag-Mn,Chit-FeMn i GAC-FeMn) odvija u dva koraka. U prvom koraku As(III) se oksiduje do As(V), dok u drugom koraku, oksidovani&nbsp; As(V)&nbsp; mehanizmom&nbsp; ligandne&nbsp; izmene&nbsp; formira&nbsp; komplekse&nbsp; na povr&scaron;ini ovih sorbenata.<br />Afiniteti sorpcije Fe-Mn binarnih oksida (na osnovu K<sub>d</sub> vrednosti)&nbsp; za As(III) opadali su u nizu Fe-Mn 3:1 &gt; Fe-Mn 1:1 &gt; Fe-Mn 6:1 &gt; Fe-Mn 9:1 odnosno kod&nbsp; As(V):&nbsp; Fe-Mn&nbsp; 6:1&nbsp; &gt;&nbsp; Fe-Mn&nbsp; 3:1&nbsp; &gt;&nbsp; Fe-Mn&nbsp; 9:1&nbsp; &gt;&nbsp; Fe-Mn&nbsp; 1:1.&nbsp; Kod magnetnih kompozita,&nbsp; najveća K<sub>d</sub> vrednost za As(III) i As(V) ustanovljena je kod&nbsp; Mag-FeMn.&nbsp; Uop&scaron;teno,&nbsp; Kd<br />vrednosti&nbsp; za&nbsp; As(III),&nbsp; kod&nbsp; magnetnih kompozita,&nbsp; opadale&nbsp; su&nbsp; u&nbsp; nizu:&nbsp; Mag-FeMn&nbsp; &gt;&nbsp; Mag-Mn&nbsp; &gt;&nbsp; Mag&nbsp; &gt;&nbsp; Mag-Fe, Slično, afinitet sorbenata za As(V), opadao je na sledeći način: Mag-FeMn &gt; Mag&nbsp; &gt;&nbsp; Mag-Fe&nbsp; &gt;&nbsp; Mag-Mn.&nbsp; U&nbsp; poređenju&nbsp; sa&nbsp; neimpregniranim,&nbsp; K<sub>d</sub> vrednosti bile su daleko veće kod obloţenih materijala, Chit-FeMn i GAC-FeMn, &scaron;to je ukazalo&nbsp; na&nbsp; značajan&nbsp; doprinos&nbsp; Fe-Mn&nbsp; binarnog&nbsp; oksida&nbsp; adsorpcionom kapacitetu neimpregniranih medija za As(III) i As(V). U&nbsp; odnosu&nbsp; na&nbsp; ostale&nbsp; ispitivane&nbsp; anjone,&nbsp; najveći&nbsp; uticaj&nbsp; na&nbsp; sorpciju&nbsp; oba&nbsp; oblika arsena&nbsp; na&nbsp; svim&nbsp; sintetisanim&nbsp; sorbentima&nbsp; uočen&nbsp; je&nbsp; kod&nbsp; fosfata,&nbsp; dok&nbsp; je&nbsp; uticaj nitrata i hlorida, u svim slučajevima bio bez značaja. Uticaj ispitivanih anjona na&nbsp; sorpciju&nbsp; As(III)&nbsp; i&nbsp; As(V)&nbsp; na&nbsp; Fe-Mn&nbsp; binarnim&nbsp; oksidima,&nbsp; magnetnim materijalima, Chit-FeMn kao i na sorpciju As(V) na GAC-FeMn, opadao je u nizu: fosfati &gt; silikati &gt; karbonati &gt; sulfati &gt; nitrati &gt; hloridi. Slično, uticaj ispitivanih&nbsp; anjona&nbsp; na&nbsp; sorpciju&nbsp; As(III)&nbsp; na&nbsp; GAC-FeMn&nbsp; je&nbsp; opadao&nbsp; na&nbsp; sledeći način: fosfati &gt; silikati &gt; sulfati &gt; karbonati &gt; nitrati &gt; hloridi.Primenom&nbsp; sme&scaron;e&nbsp; NaCl-NaOH-NaOCl&nbsp; odnosno&nbsp; primenom&nbsp; 0,1&nbsp; M&nbsp; i&nbsp; 0,5&nbsp; M&nbsp; rastvora NaOH, ustanovljeno je da se sintetisani sorbenti mogu jednostavno i&nbsp; efikasno&nbsp; regenerisati&nbsp; i&nbsp; vi&scaron;estruko&nbsp; primeniti,&nbsp; &scaron;to&nbsp; je&nbsp; od&nbsp; izuzetnog&nbsp; značaja&nbsp; sa ekolo&scaron;kog i ekonomskog aspekta.&nbsp; Najmanje smanjenje sorpcionog kapaciteta&nbsp; i za As(III) i za As(V), nakon pet ciklusa sorpcije -desorpcije, ustanovljeno je kod binarnog oksida sa Fe:Mn molskim odnosom 3:1 i Mag-FeMn.&nbsp; Na osnovu rezultata prikazanih u ovom radu, može se zaključiti da sintetisani sorbenti,&nbsp; Fe-Mn&nbsp; binarni&nbsp; oksidi&nbsp; i&nbsp; magnetni&nbsp; kompoziti,&nbsp; posebno&nbsp; Mag-FeMn, mogu&nbsp; biti&nbsp; efikasna&nbsp; i&nbsp; ekonomična&nbsp; alternativa&nbsp; skupim&nbsp; komercijalnim sorbentima&nbsp; i&nbsp; drugim&nbsp; sofisticiranim&nbsp; tehnologijama.&nbsp; Visok&nbsp; oksidacioni&nbsp; i sorpcioni kapacitet ovih&nbsp; materijala, koji obezbeđuje istovremeno uklanjanje&nbsp; oba oksidaciona oblika arsena daje veliku prednost ovim sorbentima i čini ih veoma&nbsp; atraktivnim&nbsp; i&nbsp; obećavajućim&nbsp; u&nbsp; tretmanu&nbsp; voda.&nbsp; Dodatni&nbsp; benefit<br />magnetnih&nbsp; sorbenata,&nbsp; pre&nbsp; svega&nbsp; Mag-FeMn,&nbsp; ogleda&nbsp; se&nbsp; u&nbsp; njegovoj jednostavnoj separaciji iz vodenog medijuma i recirkulaciji u sistemu. Glavne prednosti&nbsp; sintetisanih&nbsp; Chit-FeMn&nbsp; i&nbsp; GAC-FeMn,&nbsp; ogledaju&nbsp; se&nbsp; u&nbsp; mogućnosti&nbsp; njihove primene kao efikasne filtracione ispune.</p> / <p>The&nbsp; presence&nbsp; of&nbsp; inorganic&nbsp; arsenic&nbsp; in&nbsp; groundwater&nbsp; used&nbsp; for&nbsp; drinking&nbsp; water supply&nbsp; is&nbsp; a&nbsp; global&nbsp; problem.&nbsp; Different&nbsp; techniques&nbsp; such&nbsp; as&nbsp; oxidation, coagulation,&nbsp; adsorption,&nbsp; ion&nbsp; exchange,&nbsp; and&nbsp; membrane&nbsp; filtration&nbsp; have&nbsp; been developed&nbsp; and&nbsp; applied&nbsp; for&nbsp; arsenic&nbsp; removal&nbsp; from&nbsp; aqueous&nbsp; media.&nbsp; Among these&nbsp; technologies,&nbsp;&nbsp; adsorption&nbsp; is&nbsp; regarded&nbsp; as&nbsp; one&nbsp; of&nbsp; the&nbsp; most&nbsp; promising approaches to remove arsenic from water because of its high efficiency, low cost, simplicity of operation. Although many sorbents for arsenic removal are available on the market, there is still a need to identify and develop new&nbsp; lowcost&nbsp; sorbents which are highly effective in removing both oxidation states of arsenic, As(III) and As(V). This dissertation therefore presents the synthesis and&nbsp; characterization&nbsp; of&nbsp; ten&nbsp; new&nbsp; iron&nbsp; and&nbsp; manganese&nbsp; based&nbsp; sorbents specifically developed for effective As removal. The Fe- Mn binary oxides were prepared with Fe:Mn molar ratios of 1:1, 3:1,6:1 and 9:1, while four heterogeneous magnetic composites (Mag, Mag-Fe,Mag-Mn,&nbsp; Mag-FeMn)&nbsp; were&nbsp; synthesized&nbsp; by&nbsp; combining&nbsp; the&nbsp; heterogeneous nucleation&nbsp; technique&nbsp; with&nbsp; precipitation.&nbsp; The&nbsp; remaining&nbsp; two&nbsp; materials, Chit-FeMn&nbsp; and&nbsp; GAC-FeMn,&nbsp; were&nbsp; created&nbsp; by&nbsp; modifying&nbsp; the&nbsp; Chitosan&nbsp; and GAC&nbsp; biopolymers&nbsp; with&nbsp; Fe-Mn&nbsp; binary&nbsp;&nbsp; oxide&nbsp; (Chit-FeMn&nbsp; and&nbsp; GAC-FeMn).Multiple&nbsp; techniques&nbsp; were&nbsp; applied&nbsp; to&nbsp; determine&nbsp; the&nbsp; physical&nbsp; and&nbsp; chemical characteristics&nbsp; of&nbsp; the&nbsp; resulting&nbsp; sorbents&nbsp; (including&nbsp; SEM/EDS,&nbsp; XRD,&nbsp; FTIR and BET analyses). In order to establish which sorbents show&nbsp; the greatest promise for application during&nbsp; drinking&nbsp; water&nbsp; treatment,&nbsp; the&nbsp; sorption&nbsp; capacity&nbsp; of&nbsp; the&nbsp; sorbents,&nbsp; theAs(III)&nbsp; and&nbsp; As(V)&nbsp; sorption&nbsp; mechanisms,&nbsp; and&nbsp; the&nbsp; impact&nbsp; of&nbsp; various&nbsp; factors relevant to arsenic sorption, including the regeneration potential and the reuse potential of the sorbents, were all investigated in&nbsp; batch experiments. During the physical characterisation, the Fe-Mn binary oxides and magnetic materials&nbsp; were&nbsp; found&nbsp; to&nbsp; have&nbsp; relatively&nbsp; large&nbsp; specific&nbsp; surface&nbsp; areas (109-300 m 2 /g) and mesopore volumes (0.144-0.403 cm 3 /g).&nbsp; A large specific surface&nbsp; area&nbsp; and&nbsp; microporous&nbsp; structure&nbsp; was&nbsp; observed&nbsp; for&nbsp; GAC-FeMn&nbsp; (996 m 2 /g;&nbsp; 0.394&nbsp; cm 3 /g).&nbsp; In&nbsp; comparison&nbsp; with&nbsp; the&nbsp; other&nbsp; synthesized&nbsp; sorbents,&nbsp; Chit-FeMn has the smallest specific surface area and pore volume (1.99 m 2 /g; 0.014&nbsp; cm 3 /g).&nbsp; XRD&nbsp; analyses&nbsp; of&nbsp; the&nbsp; Fe-Mn&nbsp; binary&nbsp; oxides&nbsp; indicated&nbsp; that&nbsp; the phase&nbsp; structure&nbsp; of&nbsp; the&nbsp; synthesized&nbsp; Fe-Mn&nbsp; binary&nbsp; oxides&nbsp; was&nbsp; similar&nbsp; to ferrihydrate,&nbsp; while&nbsp; the&nbsp; phase&nbsp; structure&nbsp; of&nbsp; the&nbsp; magnetic&nbsp; materials&nbsp; showed&nbsp; a good agreement with the XRD diffractogram of maghemite. Investigations into As sorption process kinetics have shown that the sorption mechanism&nbsp; for&nbsp; both&nbsp; As(III)&nbsp; and&nbsp; As(V)&nbsp; on&nbsp; the&nbsp; synthesized&nbsp; sorbents&nbsp; is&nbsp; a combination&nbsp; of&nbsp; surface&nbsp; hemisorption,&nbsp; which&nbsp; takes&nbsp; place&nbsp; through&nbsp; the boundary&nbsp; layer&nbsp; of&nbsp; sorbent&nbsp; particles,&nbsp; and&nbsp; intracellular&nbsp; diffusion.&nbsp; The&nbsp; FTIR analyses&nbsp; confirmed&nbsp; that&nbsp; arsenic&nbsp; sorption&nbsp; was&nbsp; accomplished&nbsp; through&nbsp; the interactions&nbsp; of&nbsp; the&nbsp; hydroxyl&nbsp; groups&nbsp; of&nbsp; iron&nbsp; present&nbsp; on&nbsp; the&nbsp; surface&nbsp; of&nbsp; the sorbents and arsenic. In contrast to the sorption of As(V), it was also shown that&nbsp; As(III)&nbsp; sorption&nbsp; onto&nbsp; sorbents&nbsp; containing&nbsp; manganese&nbsp; oxides&nbsp; (Fe-Mn binary&nbsp; oxides,&nbsp; Mag-FeMn,&nbsp; Mag-Mn,&nbsp; Chit-FeMn&nbsp; and&nbsp; GAC&nbsp; -FeMn)&nbsp; takes place in two steps. In the first step As(III) is oxidized to As(V), while in the second&nbsp; step,&nbsp; the&nbsp; oxidized&nbsp; As(V)&nbsp; forms&nbsp; complexes&nbsp; on&nbsp; the&nbsp; surface&nbsp; of&nbsp; the sorbents via ligand exchange. The&nbsp; Fe-Mn&nbsp; binary&nbsp; oxide&nbsp; sorption&nbsp; capacities&nbsp; (expressed&nbsp; as&nbsp; Kd values)&nbsp; for As(III)&nbsp;&nbsp; followed the trend Fe-Mn 3:1 &gt; Fe-Mn 1:1 &gt; Fe-Mn 6:1 &gt; Fe-Mn 9:1, whereas the&nbsp; As(V) trend was Fe-Mn 6:1 &gt; Fe-Mn 3:1 &gt; Fe-Mn 9:1 &gt; Fe-Mn 1:1. In the magnetic&nbsp; composites, the largest&nbsp; Kd value for As(III) and As(V) was&nbsp; obtained&nbsp; for&nbsp; Mag-FeMn.&nbsp; Generally,&nbsp; the&nbsp; Kd values&nbsp; for&nbsp; As(III)&nbsp; in&nbsp; the magnetic composites decreased in the series: Mag-FeMn &gt; Mag-Mn &gt; Mag &gt; Mag-Fe.&nbsp; Similarly,&nbsp; the&nbsp; affinity&nbsp; of&nbsp; the&nbsp; sorbents&nbsp; for&nbsp; As(V)&nbsp; was&nbsp; as&nbsp; follows: Mag-FeMn&nbsp; &gt;&nbsp; Mag&nbsp; &gt;&nbsp; Mag-Fe&nbsp; &gt;&nbsp; Mag- Mn.&nbsp; In&nbsp; comparison&nbsp; to&nbsp; the&nbsp; nonimpregnated&nbsp; materials,&nbsp; the&nbsp; Kd values&nbsp; were&nbsp; much&nbsp; higher&nbsp; for&nbsp; the&nbsp;&nbsp; boated materials,&nbsp; Chit-FeMn&nbsp; and&nbsp; GAC-FeMn,&nbsp; demonstrating&nbsp; the&nbsp; significant advantage&nbsp; Fe-Mn&nbsp; binary&nbsp; oxides&nbsp; provide&nbsp; in&nbsp; increasing&nbsp; As(III)&nbsp; and&nbsp; As(V)&nbsp; adsorption capacities. One&nbsp; of&nbsp; the&nbsp; most&nbsp; problematic&nbsp; limiting&nbsp; factors&nbsp; in&nbsp; applying&nbsp; adsorption technologies during drinking water treatment is the presence of other water constituents which interfere with the adsorption process.&nbsp; Investigations into the inhibitory effect of competive anions on the adsorption of both forms of arsenic&nbsp; revealed&nbsp; that&nbsp; phosphates&nbsp; were&nbsp; the&nbsp; worst&nbsp; offenders&nbsp; in&nbsp; terms&nbsp; ofreducing&nbsp; the&nbsp; arsenic&nbsp; removal&nbsp; efficacy&nbsp; of&nbsp; sorbents&nbsp; investigated.&nbsp; From&nbsp; the largest&nbsp; to&nbsp; the&nbsp; smallest&nbsp; negative&nbsp; influence&nbsp; of&nbsp; the&nbsp; anions&nbsp; investigated,&nbsp; for As(III)&nbsp; and&nbsp; As(V)&nbsp; adsorption&nbsp; on&nbsp; Fe-Mn&nbsp; binary&nbsp; oxides,&nbsp; magnetic&nbsp; materials and Chit-FeMn, as well as As(V) adsorption on GAC-FeMn, the order was: phosphates &gt; silicates &gt; carbonates &gt; sulfates &gt; nitrates &gt; chlorides, with the presence&nbsp; of&nbsp; the&nbsp; latter&nbsp; two&nbsp; anions&nbsp; proving&nbsp; almost&nbsp; irrelevant&nbsp; to&nbsp; the&nbsp; As adsorption&nbsp; process.&nbsp; Similarly,&nbsp; the&nbsp; negative&nbsp; influence&nbsp; of&nbsp; anions&nbsp; on&nbsp; As(III) sorption on GAC-FeMn was: phosphates &gt; silicates &gt; sulphates &gt; carbonates &gt; nitrates &gt; chlorides. Another&nbsp; issue&nbsp; with&nbsp; applying&nbsp; adsorption&nbsp; in&nbsp; real&nbsp; treatment&nbsp; conditions&nbsp; is&nbsp; the need to regularly&nbsp; regenerate and/or replace the spent sorbent. In this work, a simple&nbsp; and&nbsp; efficient&nbsp; process&nbsp; for&nbsp; sorbent&nbsp;&nbsp; rfegeneration&nbsp; is&nbsp; demonstrated.&nbsp; This regeneration&nbsp; process&nbsp; can&nbsp; be&nbsp; applied&nbsp; to&nbsp; the&nbsp; sorbents&nbsp; investigated&nbsp; multiple times, and uses an NaCl-NaOH-NaOCl mixture, or 0.1 M and 0.5 M NaOH solutions.&nbsp; This&nbsp; finding&nbsp; is&nbsp; of&nbsp; great&nbsp; importance&nbsp; from&nbsp; an&nbsp; ecological&nbsp; and economic point of view. The minimum reduction in the sorption capacity for both As(III) and As(V), after five sorption-regeneration cycles, was found in&nbsp; the&nbsp; binary&nbsp; oxide&nbsp; with&nbsp; a&nbsp; 3:1&nbsp; Fe:Mn&nbsp; molar&nbsp; ratio&nbsp; and&nbsp; Mag-FeMn.&nbsp; Arsenic sorption&nbsp; behaviour&nbsp; was&nbsp; also&nbsp; investigated&nbsp; using&nbsp; real&nbsp; groundwater&nbsp; samples, with the results demonstrating the great potential of 3:1 Fe-Mn binary oxide and Mag- FeMn. However, Chit-FeMn and GAC-FeMn were less effective at adsorbing As from the groundwater samples.Based on the results presented in this dissertation, it can&nbsp; be concluded that the synthesized&nbsp; sorbents,&nbsp; especially&nbsp; the&nbsp; Fe-Mn&nbsp; binary&nbsp; oxides&nbsp; and&nbsp; magnetic composites,&nbsp; and&nbsp; Mag-FeMn&nbsp; in&nbsp; particular,&nbsp; can&nbsp; be&nbsp; efficient&nbsp; and&nbsp; economical alternatives&nbsp; to&nbsp; expensive&nbsp; commercial&nbsp; sorbents&nbsp; and&nbsp; other&nbsp; sophisticated&nbsp; As removal&nbsp; technologies.&nbsp; The&nbsp; high&nbsp; oxidation&nbsp; and&nbsp; sorption&nbsp; capacity &nbsp; of&nbsp; these materials,&nbsp; which&nbsp; ensure&nbsp; the&nbsp; simultaneous&nbsp; removal&nbsp; of&nbsp; arsenic&nbsp; with&nbsp; both oxidation states, is a large advantage for these sorbents and makes them very attractive&nbsp; and&nbsp; promising&nbsp; for&nbsp; application&nbsp; in&nbsp; drinking&nbsp; water&nbsp; treatment.&nbsp; An additional&nbsp; benefit of the magnetic sorbents, primarily Mag-FeMn, is the ease with&nbsp; which&nbsp; they&nbsp; may&nbsp; be&nbsp; separated&nbsp; from&nbsp; the&nbsp; aqueous&nbsp; medium,&nbsp; allowing&nbsp; for simple&nbsp; recirculation within a system. Similarly,&nbsp; the main advantages of&nbsp; the synthesized Chit- FeMn and GAC-FeMn are reflected in their application as effective filtration media.</p>

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