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<p>Predmet istraživanja ove doktorske disertacije bio je ispitivanje adsorpcionog pona&scaron;anja As(III) i odabranih metala (Cu(II), Cd(II), Pb(II), Cr(VI)) na amino- funkcionalizovanim vi&scaron;eslojnim ugljeničnim nanocevima, MWCNT-NH₂, na četiri odabrane pH vrednosti (3; 4,5; 6 i 11) i pri različitim sastavima vodenog rastvora (prisustvo hlorida, nitrata, sulfata i fosfata), a u cilju ispitivanja mogućnosti primene MWCNT-NH₂ za uklanjanje arsena i jona metala iz vodenih rastvora u oblasti relativno niskih koncentracija (0,01-3 mg L ^-1 ). Fokus ove doktorske disertacije<br />je bio na utvrđivanju mehanizma procesa adsorpcije u ispitivanim uslovima.&nbsp;&nbsp; Adsorpciju arsena i metala na MWCNT-NH₂ najbolje je opisao reakcioni model pseudo-drugog reda &scaron;to&nbsp; znači da adsorpcija može biti pripisana uspostavljanju hemijskih interakcija između adsorbata i vezivnih grupa na povr&scaron;ini adsorbenta. Modelovanje brzine Weber Morris-ovim difuzionim modelom ukazalo je&nbsp; na to da unutarčestična difuzija, iako sporiji korak&nbsp; od eksterne difuzije, nije jedini ograničavajući korak u procesu adsorpcije, već su za to odgovorne i interakcije ispitivanih jona sa vezivnim mestima na povr&scaron;ini adsorbenta.&nbsp; U ravnotežnim uslovima, na različitim pH vrednostima, adsorpcija se mogla opisati&nbsp; Langmuir-ovim i Freundlich-ovim adsorpcionim modelima. Kapacitet i afinitet adsorbenta, kao i sam mehanizam adsorpcije, značajno su bili uslovljeni pH vredno&scaron;ću rastvora, kako zbog karakteristika povr&scaron;ine ispitivanog adsorbenta uslovljenih pH vredno&scaron;ću, tako i zbog uticaja pH vrednosti rastvora na pojavne hemijske oblike u kojima se arsen i metali nalaze. Ispitivanje uticaja anjona pokazalo je da je prisustvo hlorida povećalo afinitet povr&scaron;ine MWCNT-NH₂ka jonima arsena i svih metala u oblasti niskih<br />koncentracija, dok je prisustvo hlorida, nitrata, sulfata i fosfata pozitivno uticalo na afinitet povr&scaron;ine (od 2 do 8 puta veći u odnosu na dejonizovanu vodu) MWCNT-NH₂<br />ka Cu(II) u oblasti vi&scaron;ih koncentracija. Najmanji uticaj anjona na afinitet povr&scaron;ine ka vezivanju metala primećen je kod hroma. Pretpostavljeni&nbsp; mehanizmi uklanjanja arsena i odabranih metala u prisustvu anjona ukljuĉuju reakcije građenja različitih vrsta spolja&scaron;nje-&nbsp; i unutra&scaron;nje-sfernih kompleksa, jonske izmene, kao i&nbsp; elektrostatičke interakcije koje se ostvaruju između pozitivno naelektrisane povr&scaron;ine MWCNT-NH_{<span style="font-size: 8.33333px;">2</span>}&nbsp;i anjona, na pH vrednostima manjim od 6,4, a koje menjaju afinitet<br />povr&scaron;ine ka jonima arsena i metala. Rezultati ove doktorske disertacije pokazuju da se ispitivani adsorbent, MWCNT-NH₂,&nbsp; može koristiti za uklanjanje arsena i te&scaron;kih metala iz vode u prisustvu različitih anjona i da, svojim adsorpcionim karakteristikama, može konkurisati komercijalnim i&nbsp; ekonomski pristupačnim adsorbentima.</p> / <p>The subject of this doctoral thesis was the examination of the adsorption behaviour of As(III), and selected metals (Cu(II), Cd(II), Pb(II), Cr(VI)) on the amino-functionalized multiwalled carbon nanotubes, MWCNT-NH₂, at four pH values (3, 4.5, 6, and 11) with different compositions of aqueous solutions (in the presence of chlorides, nitrates, sulphates and phosphates), in order to examine the possibilities of applying MWCNT-NH₂ in removal of arsenic and metal ions from aqueous solutions in relatively low concentration (0,01- 3mg L^-1). The focus of this doctoral thesis was to establish the mechanism of adsorption process in given conditions. Arsenic and metal adsorption on MWCNT-NH₂ were best described with the pseudo-second order kinetic model, which assumes that adsorption can be attributed to the establishment of chemical reactions between the adsorbate, and the binding groups at the surface of adsorbent. The Weber - Morris diffusion model indicated that intercellular diffusion, although being a slower step than external diffusion, is not the only limiting step in the adsorption process, but also that the interactions of ions with the adsorbent surface binding sites, are responsible. In equilibrium, at different pH values, the adsorption could be described by the Langmuir and Freundlich adsorption models. The capacity and affinity of the adsorbent, and adsorption mechanism, were considerably determined by the pH value of the solution, either because of the characteristics of the surface of the investigated adsorbent depending on pH value, or the effect of the solution&rsquo;s pH value on the chemical forms of arsenic and other metals. Investigation of the influence of the anion showed that the presence of chloride increased affinity of the surface of MWCNT-NH₂ to arsenic ions and to all metals in low concentration ranges, while presence of chlorides, nitrates, sulphates and phosphates had a positive impact on the affinity of the surface (2 or 8 times greater than for deionized water) MWCNT-NH₂ for Cu(II) in high concentration ranges. The smallest impact of anions to affinity of the surface to bond metals was noticed for chromium. The assumed mechanisms of removing arsenic and selected metals in the presence of anions include reactions of forming various kinds of outer- and inner-spheric complexes, ionic exchange, as well as electrostatic interaction which occur between positively charged surface of MWCNT-NH₂ and anions, for pH &lt; 6.4, and which change affinity of the surface towards arsenic and metal ions. Results of this doctoral thesis show that the investigated adsorbent, MWCNT-NH₂, can be used for the removal of arsenic and heavy metals from water, in the presence of different anions, and that with its adsorbent characteristic it can compete with commercially, and economically more affordable adsorbents.</p>

<p>Fokus ove doktorske disertacije je bilo izučavanje sorpcionog pona&scaron;anja tri herbicida koji se nalaze na listi prioritetnih supstanci prema Okvirnoj Direktivi o vodama EU (2000/60/EC) sa generalnim ciljem dobijanja podataka korisnih za prioritizaciju na osnovu novog fundamentalnog znanja o efikasnosti (ad)sorpcije za uklanjanje ovih<br />supstanci iz&nbsp; vode u lokalno specifičnim uslovima. Odabrani su ksenobiotici različite rastvorljivosti, hidrofobnosti i donorsko-akceptorskih osobina, koji&nbsp; pripadaju&nbsp; različitim klasama&nbsp; herbicida (dinitroanilinski-trifluralin, hloroacetamidni-alahlor i triazinski-&nbsp; atrazin). Prva faza je obuhvatala karakterizaciju sorbenata i vodenih matriksa .U sintetičkom matriksu, trifluralin pokazuje veći afinitet na ispitivanim sedimentima u odnosu na alahlor i atrazin. I u slučaju organoglina, sorpcija je najizraženija za trifluralin. Alahlor i atrazin pokazuju slične sorpcione kapacitete na TMA-K, dok je na TMA-B, sorpcija izraženija za alahlor u odnosu na atrazin. U&nbsp; zavisnosti od prirodnog matriksa, na oba sedimenta, najveće&nbsp; Kd vrednosti su dobijene za trifluralin, dok su Kd vrednosti za atrazin i alahlor&nbsp; bile veoma slične ili&nbsp;pak veće za atrazin. U slučaju organoglina, vrednosti&nbsp; K_d su rasle sa porastom log&nbsp; K_OW vrednosti herbicida na TMA-K u oba prirodna matriksa. Kada je u pitanju TMA-B, rast K_dvrednosti sa rastom log&nbsp; K_OW vrednosti uočava se u povr&scaron;inskom matriksu pri C_e&nbsp; = 0,05 mg/l i 0,5 mg/l, i podzemnom matriksu pri najvećoj ravnotežnoj koncentraciji C_e&nbsp; = 0,5 mg/l. Kao najefikasniji sorbenti su se pokazali&nbsp; TMA-B&nbsp;(Kd&nbsp; = 10,5 -&nbsp; 483 l/kg) i model sediment (Kd = 16,4 -&nbsp; 761 l/kg). Odsustvo jasne linearne korelacije izmeĎu&nbsp; Kd i&nbsp; % TOC upućuje na važnost interakcija mineralne faze i herbicida. U slučaju sedimenata nisu utvrđene korelacije K_d sa log&nbsp; K_OW&nbsp;vrednostima, dok kod organoglina one postoje. K<span id="cke_bm_184S" style="display: none;">&nbsp;</span>_d<span id="cke_bm_184E" style="display: none;">&nbsp;</span> /K_OW odnosi su najveći kod atrazina na svim sorbenti<span id="cke_bm_185E" style="display: none;">&nbsp;</span>ma pa se pretpostavlja da on najvi&scaron;e učestvuje u&nbsp; uspostavljanju specifičnih interakcija zbog svojih donorsko-akceptorskih osobina. &Scaron;to se tiče uticaja DOC,&nbsp; zaključuje se da poreĎenje efikasnosti sorbenata treba sprovoditi u prirodnim matriksima jer sorpcioni koeficijenti variraju u zavisnosti od&nbsp;koncentracije polutanata, tipa i sadržaja DOC. Kolonskim eksperimentima je pokazano da atrazin i alahlor prolaze kroz kolonu sedimenta, dok je trifluralin skoro u potpunosti adsorbovan i u vrlo maloj koncentraciji detektovan u efluentu &scaron;to je u saglasnosti sa rezultatima &scaron;aržnih eksperimenata na ovom sorbentu. Procenjeni faktor retardacije pomoću modela TransMod za atrazin je veći u prirodnim matriksima (R <span id="cke_bm_190S" style="display: none;">&nbsp;</span>_d<span id="cke_bm_190E" style="display: none;">&nbsp;</span> = 54 i R_d = 55 u podzemnoj i povr&scaron;inskoj vodi, redom) nego u sintetičkoj&nbsp;vodi (R_d = 40). Kod alahlora nisu uočene značajne promene faktora retardacije meĎu matriksima (R_d = 30-35). Ovi rezultati su suprotni očekivanjima na osnovu hidrofilnosti ksenobiotika i mogu biti&nbsp; rezultat upravo interakcija sa organskim materijama koje su bile izražene u kolonskim testovima, verovatno i vi&scaron;e nego u &scaron;aržnim testovima gde se nije pojavilo povećanje R_d vrednosti u prirodnim matriksima u odnosu na sintetički matriks.&nbsp; Bez obzira &scaron;to je&nbsp; alahlor hidrofobniji od atrazina, u uslovima datog matriksa i sorbenta ispoljava slične (&scaron;aržni testovi) ili<br />slabije sorpcione karakteristike&nbsp; (kolonski testovi)&nbsp; koje upućuju na mobilnost kroz prvi za&scaron;titini sloj.&nbsp; Treća faza je obuhvatala ispitivanje adsorpcije herbicida na aktivnim ugljevima u prahu. Ispitana je kinetika adsorpcionog procesa određivanjem koeficijenta za unutarčestični prenos mase herbicida u sirovim i ozoniranim prirodnim matriksima. Određena je efikasnost uklanjanja herbicida na razlilčitim ugljevima u prahu. Efikasnost uklanjanja se kretala u različitim opsezima u zavisnosti od odabranog uglja, vodenog matriksa i doze uglja. Na komercijalnim ugljevima najveća postignuta efikasnost (doza uglja od 15 mg/l) za&nbsp; alahlor iznosi u povr&scaron;inskoj vodi 95%, a u podzemnoj 76%. Za atrazin to je u povr&scaron;inskoj vodi 58% i u podzemoj vodi 56%, a za trifluralin u povr&scaron;inskoj vodi 87%, a u podzemnom matriksu 92%. Na uglju sitnih čestica koji se koristi u kombinaciji sa membranskom filtracijom ove<br />vrednosti su&nbsp; i veće. Stepen uklanjanja DOC na komercijalnim ugljevima (pri dozi od 15 mg/l) iznosi do 57% za povr&scaron;inski matriks i do&nbsp; 51% za podzemni matriks. Slična efikasnost u uklanjanju DOC je postignuta i na uglju sitnih čestica u oba matriksa. Ozonizacija je ispoljila očekivan negativan uticaj, vi&scaron;e ili manje izražen. U slučaju ksenobiotika, uticaji ozonizacije su bili različiti, u zavisnosti od primenjenog uglja, matriksa i supstance. Najizraženiji uticaj je kod alahlora,&nbsp; i to u negativnom smislu,<br />zbog pada efikasnosti uklanjanja, verovatno zbog kompeticije sa organskom materijom ili efekta solubilizacije. U nekim slučajevima, ali mnogo manje, taj efekat je primećen i kod trifluralina. Na oba komercijalna uglja primećen je pozitivan uticaj ozonizacije na uklanjanje atrazina, ali u različitim matriksima,&nbsp; pa se može spekulisati<br />pretpostavljanjem da dolazi do favorizovane raspodele u novim oblogama&nbsp; POM na uglju formiranim nakon ozonizacije koje su i dovoljno adsorbabilne, ali i sa dovoljno reaktivnim osobinama za asociranje sa polarnim supstancama, &scaron;to je delimično i potvrđeno rezultatima adsorpcione analize.&nbsp;&nbsp;</p> / <p>The focus of&nbsp; this doctoral thesis was the study of the sorption behavior of three herbicides which are on the list of priority substances according to Water Framework Directive (2000/60/EC). The aim&nbsp; was&nbsp; to obtain the&nbsp; data useful for prioritization on the basis of the&nbsp; new fundamental knowledge about (ad) sorption efficiency&nbsp; for the removal of these substances from the&nbsp; locally specific water matrices. Selected xenobiotics&nbsp; were&nbsp; differing&nbsp; in&nbsp; solubility, hydrophobicity, and donor-acceptor properties, which belong to different classes of compounds(trifluralin as herbicide, alachlor as chloracetamide herbicide and atrazine as triazine herbicide).&nbsp; In the first phase&nbsp; of the thesis&nbsp; characterization&nbsp; of sorbents and water matrices&nbsp; was performed. The aim of the second phase was the testing&nbsp; of&nbsp; the sorption and<br />desorption of organic xenobiotics in the sediments and organoclays. The equilibrium&nbsp; sorption parameters and removal efficiencies of herbicides were determined in different water matrices.&nbsp; In the synthetic matrix, trifluralin showed a higher sorption affinity onto tested sediments in comparison to the alachlor and atrazine. In the case of organoclays, sorption was mostly&nbsp; pronounced for trifluralin. Alachlor and atrazine have similar sorption capacities onto the TMA-K. For the TMA-B, the sorption was more pronounced for alachlor than atrazine. Depending on the natural water matrices,&nbsp; the highest&nbsp; K_d values were obtained for trifluralin onto both sediments. The&nbsp; K_d values for atrazine and alachlor were very similar or even greater for atrazine. In the case of organoclays, K_d values increased with increasing log&nbsp; K_OW values of herbicides onto TMA-K in both natural matrices. When it comes to TMA-B,&nbsp; K_d&nbsp; valuesincreased with increasing log&nbsp; K_OW values in&nbsp; the surface matrix for<br />C_e = 0,05 mg/l and 0,5 mg/l, and in groundwater at the highest equilibrium&nbsp; concentration&nbsp; C<span id="cke_bm_506S" style="display: none;">&nbsp;</span>_e<span id="cke_bm_506E" style="display: none;">&nbsp;</span>&nbsp; = 0,5 mg/l. TMA-B (K_d = 10,5&nbsp; -&nbsp; 483 l/kg) and model&nbsp; sediment&nbsp; (kd= 16,4 to 761 l/kg) were the most efficient s<span id="cke_bm_507E" style="display: none;">&nbsp;</span>orbents. The absence of&nbsp; the&nbsp; clear linear correlation between&nbsp; K_d and % TOC&nbsp; indicates the importance of the interaction of mineral phases and herbicides. Correlation between K<span id="cke_bm_513S" style="display: none;">&nbsp;</span>_d<span id="cke_bm_513E" style="display: none;">&nbsp;</span> and K_OW values did not existed in the case of sediments,&nbsp; contrary to the organoclays.&nbsp; Since K<span id="cke_bm_519S" style="display: none;">&nbsp;</span>_d<span id="cke_bm_519E" style="display: none;">&nbsp;</span> /K_oW ratios were the h<span id="cke_bm_520E" style="display: none;">&nbsp;</span><span id="cke_bm_514E" style="display: none;">&nbsp;</span>ighest for atrazine onto all sorbents, it&nbsp; was&nbsp; assumed that atrazine mostly participate in specific interactions due to its donor-acceptor properties. Regarding the&nbsp; influence of DOC on sorption, it was concluded that a comparison of sorbents efficiencies should be carried in&nbsp; native matrices as sorption coefficients vary depending on the concentration of pollutants, the type and content of DOC. Column&nbsp; experiments showed that atrazine and alachlor passed through the column of the sediment, while the trifluralin almost completely was adsorbed and in very low concentrations detected in the effluent which is in accordance with the results of the&nbsp; batch experiments.&nbsp; Estimated retardation factors of atrazine were higher in natural matrices (R<span id="cke_bm_525S" style="display: none;">&nbsp;</span>_d<span id="cke_bm_525E" style="display: none;">&nbsp;</span>= 54 and R_d = 55 in groundwater and surface water, respectively) than in&nbsp; the synthetic water (R_d= 40_{). I}n the case of alachlor, retardation factors were similar among water matrices (R_d = 30-35). These results are in the opposition&nbsp; based on the xenobiotic hydrophilicity, and they could be the consequence of interaction with the organic matter&nbsp; present&nbsp; in the column tests, probably more than in the batch tests. Estimations of&nbsp; R_d based on batch tests&nbsp; did not show an increase of R_d values in natural matrices, in comparison to the synthetic matrix. More hydrophobic alachlor, in the circumstances of the sorbent matrix exerts similar&nbsp; (batch&nbsp; tests) or lower sorption (column tests) characteristics that indicate mobility through the first protective layer.<span id="cke_bm_526E" style="display: none;">&nbsp;</span> The third phase&nbsp; included herbicide adsorption tests onto powdered activated carbons. The adsorption kinetics was examined by determining the intraparticle mass transfer coefficients for herbicides in raw and ozonated natural water matrices. The removal efficiencies of herbicides for different powdered activated carbons were determined. Removal efficiencies were in different ranges depending on the selected carbon, water matrix and carbon dose. The highest removal efficiencies&nbsp; for commercial carbons (for carbon dose of 15&nbsp; mg/l)&nbsp; for&nbsp; alachlor were 95% and 76% in surface and groundwater, respectively. The highest&nbsp; removal of atrazine was&nbsp; 58% in surface water and 56% in groundwater. In thecase of trifluralin, removal efficiencies were&nbsp; 87% in surface water and 92% in groundwater. The removal efficiencies for the carbon with fine particles&nbsp; (usually&nbsp; used in combination with a membrane filtration)&nbsp; were greater. The removal of DOC&nbsp; &nbsp; by&nbsp; commercial carbons (at the dose of 15 mg/l) was less than 57% in the surface water and 47% in groundwater. A similar efficiency in DOC removal was achieved for the carbon with fine particles in both water matrices. Ozonation showed the expected &nbsp; negative influence on&nbsp; DOC&nbsp; removal efficiencies, more or less pronounced. In the case of xenobiotics, ozonation influence was different, depending on the applied carbon and xenobiotic. The most important negative influence was&nbsp; in the case of alachlor probably due to competition with organic matter or solubilization effect. The&nbsp; same, but less pronounced effect was observed for trifluralin. The positive influence of ozonation was observed in removal of atrazine&nbsp; by&nbsp; both commercial carbons but in &nbsp; different water matrices.&nbsp; One can speculate that it comes to the favorable distribution in new NOM coatings on carbons formed upon ozonation, which are sufficiently adsorbable, but with enough reactive qualities for association with polar substances, which is partly confirmed by the results of adsorption analysis.</p>

<p>Uklanjanje amonijaka iz podzemnih voda u cilju dobijanja<br />pijaće vode predstavlja značajan problem, koji se do sada<br />re&scaron;avao primenom različitih postupaka. Poznato je da zeoliti<br />kao prirodni jonoizmenjivači i adsorbenti kvalitetno vezuju<br />amonijum jone u svoju alumosilikatnu matricu. Njihova<br />efektivnost, u različitim tehnolo&scaron;kim procesima, zavisi od<br />fizičko-hemijskih osobina, koje su usko povezane sa njihovim<br />geolo&scaron;kim nalazi&scaron;tima, kada se govori o prirodnim zeolitima.<br />Pored prirodnih zeolita u praksi se koriste i sintetički zeoliti<br />dobijeni raznim postupcima. Danas, je komercijalna primena<br />sintetičkih zeolita rasprostranjenija u odnosu na primenu<br />prirodnih, zbog čistoće kristalnih proizvoda i uniformne<br />veličina čestica. Crystal-Right&trade; (CR-100) je zeolit koji spada u<br />grupu najizdržljivijih proizvedenih minerala. Ovaj zeolit<br />podiže pH vrednost tretiranih voda, dok istvremeno smanjuje<br />tvrdoću i uklanjanja gvožđe i mangan. Ovo pode&scaron;avanje pH i<br />uklanjanje nepoželjnih mineralnih materija postiže se izvrsnim<br />osobinama ovog zeolita u pogledu filtriranja, ali i ispiranja<br />nakon primene.<br />Maksimalna količina adsorbovanog amonijaka iznosi 2,31 mg<br />(98%) i 2 mg (87%), iz model rastvora i uzorka podzemne,<br />bunarske vode, redno. Prisustvo drugih komponenti u<br />bunarskoj vodi uzrokuje promene u količini adsorbovanog<br />amonijaka na zeolitu. Najbolje uklanjanje postignuto je za<br />jone kalijuma već sa najmanjim masama upotrebljenog<br />zeolita. Nasuprot tome, joni kalcijuma i magnezijuma se pri<br />nižim vrednostima doziranja zeolita slabije uklanjaju iz<br />bunarske vode, dok sa porastom doziranja raste i efikasnost<br />uklanjanja na svim posmatranim temperaturama.<br />Izbor adsorpcione izoterme je pokazao da najbolje rezultate<br />daje Freundlich-ova adsorpcione izoterme, a rezultati<br />aproksimacije ukazuju na fizičku adsorpciju na heterogenoj<br />povr&scaron;ini. Negativne vrednosti entropije aktivacije upućuju na<br />zaključak da se radi o asocijativnoj adsorpciji amonijaka na<br />povr&scaron;inu zeolita, odnosno da postoji interakcija između<br />adsorbovanih molekula. Vrednosti entalpije aktivacije od<br />15,096 kJ/mol i 28,978 kJ/mol, za model rastvor i realan<br />sistem, redno, upućuju da se radi o endotermnom procesu,<br />&scaron;to i potvrđuju podaci o ravnotežnim koncentracijama na<br />različitim temperaturama.<br />Tokom eksperimenata izvedenih sa poluindustrijskom<br />kolonom ispunjenom zeolitom Crystal Right&trade; (tip CR-100)<br />potvrđena je efikasnost u uklanjanju zeolita iz bunarske vode.<br />Između ispitanih modela za određivanje kinetike u kolonskom uređaju najboljim se pokazao model Yoon-Nelson-a.<br />Koeficijent linearne korelacije za model Yoon-Nelson-a iznosi -<br />0,975, dok je koeficijent determinacije imao vrednosti 0,950.<br />Iako je model razvijen jednokomponentne sisteme pokazao<br />se kao zadovoljovajući iako se radi o realnom sistemu<br />podzemne bunarske vode koja sadrži brojne rastvorene<br />supstance, katjone zemnoalkalnih i alkalnih metala, huminske<br />kiseline, anjone itd. Može se primetiti da je postignuto<br />zadovoljavaće slaganje eksperimentalnih podataka o<br />vremenu probaja sloja (50%) sa Yoon-Nelson-ovim modelom,<br />eksperimentalno određeno vreme proboja sloja iznosi oko 59<br />časova, dok je modelom dobijeno vreme 62 časa. Konstanta<br />brzine Yoon-Nelson-ovog modela iznosi 0,051 1/h.</p> / <p>Removing ammonia from groundwater to obtain drinking<br />water is an important issue, which is so far solved using<br />different methods. It is known that zeolites as natural ion<br />exchangers and adsorbents that bind ammonium ions in its<br />aluminosilicate matrix. Their effectiveness in various<br />technological processes depends on the physical and<br />chemical properties, which are closely related to their<br />geological sites, when it comes to natural zeolites. In addition<br />to the natural zeolites in practice synthetic zeolites are used.<br />Today, the commercial application of synthetic zeolites is<br />widespread in relation to the use of natural, due to the purity<br />of crystal products and uniform particle size. Crystal-Right &trade;<br />(CR-100) is a zeolite among the most durable minerals<br />produced. This zeolite raises the pH of the treated water, while<br />the same time it reduces the hardness and remove iron and<br />manganese. This pH adjustment and removal of undesirable<br />mineral substances is achieved by the excellent characteristics<br />of the zeolite in terms of filtering, and rinsing after application.<br />The maximum amount of adsorbed ammonia at 2.31 mg<br />(98%) and 2 mg (87%), from the model solution and the<br />sample of groundwater, well water, respectively. The presence<br />of other components in the well water causes changes in the<br />amount of ammonia adsorbed on zeolite. Selection of<br />adsorption isotherms showed that the best results are<br />achieved by Freundlich&#39;s adsorption isotherm, and the results<br />indicate physical adsorption on heterogeneous surfaces.<br />Negative values of entropy of activation lead to the<br />conclusion that it is associative adsorption of ammonia on the<br />surface of the zeolite, or that there is an interaction between<br />the adsorbed molecules. The values of enthalpy of activation<br />of 15,096 kJ / mol and 28,978 kJ / mol, for the model solution<br />and real system, respectively, indicating that it is an<br />endothermic process, which is confirmed by data on the<br />equilibrium concentrations at different temperatures.<br />Experiments conducted with the pilot plant column filled with<br />zeolite Crystal Right &trade; (type CR-100) confirmed the<br />effectiveness in removing zeolite from well water. Among the<br />surveyed models to determine the kinetics of the column<br />device Yoon-Nelson&#39;s model has proven to be the best. The<br />linear correlation coefficient for the model Yoon-Nelson&#39;s is -<br />0.975, and the value of the coefficient of determination was 0.950. Although the model developed for one-component<br />systems it is proved to be satisfactory for ground water<br />ammonia adsorption. The agreement between experimental<br />data on the breakthrough point at 50% concentration (59<br />hours) with Yoon-Nelson&#39;s model, is good (62 hours). Constant<br />of Yoon-Nelson&#39;s model is 0.051 1 / h.</p>

<p>U prvom delu rada ispitana je adsorpcija četiri grupe organskih&nbsp;jedinjenja: (1) nitroaromatičnih (nitrobenzen), (2) nepolarno alifatičnih&nbsp;(heksan), (3)&nbsp; monoaromatičnih (benzen, toluen, 1,2,3- i 1,2,4-trihlorbenzen) i (4) policikličnih aromatičnih ugljovodonika, PAH&nbsp;(naftalen, fenantren, piren i fluoranten) na vi&scaron;eslojnim ugljeničnim&nbsp;nanocevima (od eng. multiwalled carbon nanotubes, MWCNTs). Cilj&nbsp;ovog dela rada bio je pronaći korelaciju između parametara adsorpcije i&nbsp;fizičko-hemijskih karakteristika organskih molekula, kao i parametara&nbsp;<br />adsorpcije i karakteristika adsorbenata. Na osnovu dobijenih korelacija&nbsp;predložiti mehanizam adsorpcije ispitivanih organskih molekula na&nbsp;MWCNT-u.</p><p>U cilju ispitivanja uticaja kiseoničnih funkcionalnih grupa na povr&scaron;ini&nbsp;MWCNT-a odabrane su tri vrste MWCNT-a: originalni, nemodifikovani&nbsp;MWCNT (OMWCNT) i dve vrste funkcionalno modifikovanog&nbsp;MWCNT-a koji su dobijeni tretiranjem sa kiselinom tokom 3 h&nbsp;(FMWCNT3h) i 6 h (FMWCNT6h). Sve adsorpcione izoterme opisane&nbsp;<br />su Freundlich-ovim modelom. Nelinearnost izotermi bila je u opsegu od&nbsp;0,418 do 0,897. Rezultati pokazuju da dobijeni afiniteti adsorpcije (za ravnotežnu koncentraciju 50% rastvorljivosti jedinjenja u vodi, K_d0,5 S_W) za PAH-ove rastu sa povećanjem specifične povr&scaron;ine (SP) adsorbenta. Veći afiniteti adsorpcije dobijeni su za velike molekule kao &scaron;to su PAH-ovi u poređenju sa malim molekulima (benzen, toluen i heksan) &scaron;to može biti posledica veće kontaktne povr&scaron;ine između većih molekula i povr&scaron;ine adsorbenta. Pozitivna korelacija između afiniteta adsorpcije i hidrofobnosti molekula ukazuje da hidrofobne interakcije dominantno kontroli&scaron;u adsorpciju ispitivanih organskih jedinjenja, osim u slučaju nitobenzena. Da bi se ispitao uticaj &pi;-&pi; interakcija,&nbsp; K_d za odabranu ravnotežnu koncentraciju su normalizovane sa hidrofobno&scaron;ću molekula pri čemu su dobijeni odgovarajući&nbsp; K_d/K_OW&nbsp;odnosi. Za sva ispitivana jedinjenja K_d/K_OW<font size="1">&nbsp;</font>odnosi na svim ispitivanim MWCNT rastu u sledećem nizu: nepolarni alifatični &lt; monoaromatični &lt; PAH-ovi &lt; nitrobenzen, &scaron;to ukazuje da &pi;-&pi; interakcije značajno pobolj&scaron;avaju adsorpciju aromatičnih jedinjenja na MWCNT-u. Snažne interakcije između MWCNT-a i nitrobenzena posledica su formiranja &pi;-&pi; elektron donorsko-akceptorskih (EDA) interakcija izemđu nitroaromatičnih molekula (elektron akceptori)i visoko polarizovane ugljenične povr&scaron;ine nanocevi (elektron donori). Na osnovu dobijenih rezultata može se uočiti da se pri adsorpciji ispitivanihorganskih molekula na MWCNT-u istovreme odigrava vi&scaron;e mehanizama.</p><p>U drugom delu rada ispitan je uticaj ugljeničnog nanomaterijala (od eng.&nbsp;carbon based nanomaterial, CNM) natransport odabranih organskih&nbsp;jedinjenja (1,2,3- i 1,2,4-trihlorbenzena, naftalena, fenantrena, pirena i&nbsp;fluorantena) kroz sediment Dunava. Cilj ovog dela rada bio je ispitati&nbsp;mehanizam transporta odabranih organskih jedinjenja u prisustvu i&nbsp;odsustvu CNM. C/C_0&nbsp;vrednosti, dobijene za vreme trajanja eksperimenta&nbsp;<br />(t=96 h), ispitivanog jedinjenja u eluatu kolone napunjene samo&nbsp;sedimentom rastu u sledećem nizu: fluoranten &lt; piren &lt; fenantren &lt;&nbsp;1,2,4-trihlorbenzen &lt; 1,2,3-trihlorbenzen &lt; naftalen. U cilju ispitivanja&nbsp;uticaja hidrofobnosti ispitivanih molekula na sorpciju u neravnotežnim&nbsp;uslovima, dobijene vrednosti C/C₀ ispitivanih molekula su korelirane sa&nbsp;hidrofobno&scaron;ću molekula. Uočena je negativna korelacija &scaron;to ukazuje da&nbsp;hidrofobniji molekuli pokazuju duže vreme zadržavanja na koloni, a time&nbsp;i veću neravnotežnu sorpcijutokom transporta.&nbsp;</p><p>U prisustvu FMWCNT3h u koloni kojaje napunjena sedimentom može&nbsp;se uočiti da su koncentracije ispitivanih jedinjenja u eluatu manje za 2-3&nbsp;puta. Pri datim uslovima procenat detektovane koncentracije ispitivanog&nbsp;jedinjenja u eluatu raste u sledećem nizu: fluoranten &lt; fenantren &lt; piren &lt; naftalen &lt; 1,2,4-trihlorbenzena &lt; 1,2,3-trihlorbenzen. Predloženi mehanizam je sledeći: na eksperimentalnoj pH (pH=6,5) karboksilne grupe na FMWCNT3h su negativno naelekrisane, s druge strane tačka nultog naelektrisanja sedimenta Dunav je 4, &scaron;to ukazuje da je ukupna povr&scaron;ina pri pH=6,5 negativno naelektrisana. Međutim, metalni oksidi i hidroksidi gvožđa, aluminijuma i nikla na povr&scaron;ini sedimenta uzrokuju pozitivno naelektrisane centre &scaron;to dovodi do depozicije FMWCNT3h kao posledica elektrostatičkog privlačenja. Pri transportu organskih jedinjenja kroz sediment Dunava u prisustvu FMWCNT3h dolazi do simultane sorpcije organskih jedinjenja na organskom ugljeniku sedimenta i do adsorpcije na FMWCNT3h. Kada se pH vrednost poveća smanjuje se pozitivno naelekrisanje metalnih&nbsp; oksida i hidroksida na povr&scaron;ini sedimenta &scaron;to dovodi do povećane mobilnosti FMWCNT3h, a time i organskih jedinjenja adsorbovanih na njima. Svi rezultati ukazuju da pH vrednost ima veoma značajnu ulogu i može povećati &nbsp;transport funkcionalizovanog MWCNT-a, a time i transport organskih molekula adsorbovanih na njima.</p> / <p>The first part of the thesis investigates the adsorption of four&nbsp;groups of organic compounds (OCs): (1) nitroaromatics (nitrobenzene),&nbsp;(2) nonpolar aliphatics (hexane), (3) monoaromatics (benzene, toluene,&nbsp;1,2,3- and 1,2,4-trichlorobenzene) and (4) polycyclic aromatic&nbsp;hydrocarbons (PAHs, napthalene,&nbsp; phenanthrene, pyrene and&nbsp;fluoranthene) on multiwalled carbon nanotubes (MWCNTs). This part of&nbsp;the work aimed to find a correlationbetween the adsorption parameters&nbsp;and physical-chemical properties of the organic molecules, as well as the&nbsp;parameters of adsorption and the characteristics of the adsorbents. On the&nbsp;basis of the obtained correlations the adsorption mechanism was&nbsp;proposed. In order to investigate the influence which oxygen containing&nbsp;functional groups exert on the adsorption process, three MWCNTs were&nbsp;used: the pristine (original, as-received) MWCNTs (OMWCNT) and two&nbsp;<br />MWCNTs functionally modified by acid treatment of OMWCNT over 3&nbsp;h and 6 h (FMWCNT3h, FMWCNT6h). All adsorption isotherms well&nbsp;fitted with the Freundlich model. The nonlinearity of the isotherms&nbsp;ranged from 0.418 to 0.897. The results show that K_d&nbsp;values for PAHs&nbsp;increased with increasing specific surface areas (SSAs). The adsorption&nbsp;affinities of the larger molecular size OCs (PAHs) were higher &nbsp;than those of the smaller size OCs (benzene, toluene and hexane) which is probably due to their large contact area with the surface of the adsorbent. Adsorption of OCs on MWCNTs was mainly controlled by hydrophobic interactions, except for the nitroaromatic compound, as shown by the increasing adsorption affinities with the compound&rsquo;s hydrophobicity. K_OW-normalized adsorption coefficients (K_d/K_OW) for all the investigated compounds on all the MWCNTs followed the order: nonpolar aliphatic &lt; monoaromatics &lt; PAHs &lt; nitroaromatic, implying that &pi;-&pi; interactions enhanced the adsorption of aromatics on the MWCNTs. It can be concluded that the strong adsorptiveinteractions between the MWCNTs and nitroaromatics was due to the &pi;-&pi; electron-donor&ndash;acceptor (EDA) interaction between nitroaromatic molecules (electron acceptors) and the highly polarisable graphene sheets(electron donors) of the carbon nanotubes. Based on the obtained results, it can be concluded that multiple mechanisms control the adsorption of organic compounds on MWCNTs.</p><p>In the second part, the influence of carbon based nanomaterials CNM on&nbsp;transport of selected organic compounds (1,2,3 - and 1,2,4-trichlorobenzene, naphthalene, phenanthrene, pyrene and fluoranthene)&nbsp;through sediment Danube was investigated. &nbsp;The aim of this part of the&nbsp;work was to investigate the transport mechanism of selected organic&nbsp;compounds in the presence and absence of CNM. The C/C_0&nbsp;values for the&nbsp;tested compounds in the eluate of the column filled with sediment only&nbsp;increased in the following order: fluoranthene &lt;pyrene &lt;phenanthrene&nbsp;&lt;1,2,4-trichlorobenzene &lt;1,2,3-trichlorobenzene &lt;naphthalene. In order&nbsp;to investigate the influence of&nbsp; hydrophobicity of the investigated&nbsp;compounds on the nonequilibrium sorption, the obtained C/C_0&nbsp;values (for&nbsp;the duration of the experiment, t = 96 h) for these molecules were&nbsp;correlated with the hydrophobicity of the molecules. There was a&nbsp;negative correlation, indicating that more hydrophobic molecules show&nbsp;long residence times in the column, and thus had higher non-equilibrium&nbsp;sorption during transport. In the presence of FMWCNT3h in the column&nbsp;filled with sediment, it can be observed that the concentrations of&nbsp;compounds in the column eluate decreased by factors of 2-3. C/C_0&nbsp;values&nbsp;for the investigated compounds in the eluate increased in the following&nbsp;order: fluoranthene &lt;phenanthrene &lt;pyrene &lt;naphthalene &lt;1,2,4-trichlorobenzene &lt;1,2,3-trichlorobenzene. The proposed mechanism is as&nbsp;follows: under the experimental pH (pH = 6.5), carboxyl groups are&nbsp;negatively charged on the surface of FMWCNT3h and the point of zero&nbsp;charge of the Danube sediment is 4, which indicates thatthe total surface of the Danube sediment at pH 6.5 isnegatively charged. However, metal oxides and hydroxides of iron, aluminum and nickel on the surface of the sediment cause a positively charged centre that leads to the deposition of FMWCNT3h as a result of electrostatic attraction. Transport of organic compounds through the Danube sediment in the presence FMWCNT3h leads to the simultaneous &nbsp;sorption oforganic compounds on the sediment organic carbon and the adsorption of &nbsp;FMWCNT3h. When the pH increased, the positive charge of metal oxides and hydroxides on the sediment surface decreased, which leads to increased FMWCNT3h mobility and thus the organic compounds adsorbed on them. All results indicate that the pH value plays animportant role and can increase the transport of functionally modified MWCNT&#39;s, and thus the transport of organic molecules adsorbed on them.&nbsp;</p>

<p>This dissertation investigates the factors which affect the removal of arsenic from groundwater by adsorption and coagulation technologies, including the interactions between As and natural organic matter (NOM). Humic acid (HA) was utilised as an NOM analogue, and was shown to be capable of both complexing and oxidising As, depending upon the prevailing conditions. The arsenic removing capabilities of three iron oxide coated sands (IOCS) were investigated, including IOCSW, a waste material from a local drinking water treatment plant generated during the removal of iron and manganese. IOCSW was highly effective at removing both As(V) and As(III) from synthetic water matrices (qmax = 78.3 &micro;g As(V)/g and 99.1 &micro;g As(III)/g). The negative effects of competitive anions (phosphates, silicates and HA) on arsenic removals were not significant enough to preclude the application of IOCSW for arsenic removal during drinking water treatment. The removals of both As and NOM by coagulation and enhanced coagulation with pH correction and preoxidation were also investigated. As(V) &nbsp;was more readily removed by coagulation than As(III), so that the most efficient coagulation treatment investigated for arsenic and NOM removal applied preozonation with subsequent combined coagulation with polyaluminium chloride and ferric chloride. Different groundwaters displayed large variations in the As and NOM removal behaviours. Response surface methodology (RSM) was therefore applied to investigate &nbsp;the interactions between As and NOM during ferric chloride coagulation and optimise their combined removals. Multiple interaction effects were observed during this investigation, highlighting the importance of utilizing RSM to optimise drinking water treatment technologies.</p> / <p>Ova disertacija ispituje faktore koji utiču na uklanjanje arsena iz podzemne vode primenom adsorpcija i koagulacije, uključujući i interakcije između arsena i prirodnih organskih materija (POM). Huminska kiselina (HA) je korisćena kao model za POM, a pokazano je da može i da kompleksira i da oksiduje As, u zavisnosti od eksperimentalnih uslova. Ispitivane su mogućnosti uklanjanja arsena za tri peska obložena gvožđe oksidom (IOCS), uključujući IOCSW, koji je dobijen sa postrojenja za tretman vode za piće i potiče iz procesa uklanjanja gvožđa i mangana. IOCSW se pokazao kao visoko efikasan za uklanjanje As(V) i As(III) iz sintetičkih vodenih matriksa (q_max = 78.3 &micro;g As(V)/g i 99.1 &micro;g As(III)/g). Negativni efekti kompetirajućih jona (fosfata, silikata i HA) na uklanjanje arsena nisu bili dovoljno značajni da bi se isključila primena IOCSW za uklanjanje arsena tokom tretmana vode za piće. Zajedničko uklanjanje As i POM koagulacijom i unapređenom koagulacijom uz pode&scaron;avanje pH i kombinovanje sa oksidacionim predtretmanima je takođe ispitivano. Bolje uklanjanje koagulacijom postignuto je za As(V) u odnosu na As(III), stoga se kao najefikasniji ispitivani koagulacioni tretman pokazalo uklanjanje arsena i POM primenom predozonizacije praćene kombinovanom koagulacijom sa polialuminijum hloridom i gvožđe hloridom. Ispitivanja na različitim podzemnim vodama, pokazala su velike varijacije u pona&scaron;anju As i POM tokom tretmana. Iz tog razloga je primenjena metodologija odzivne povr&scaron;ine (RSM) u cilju ispitivanja interakcija između As i POM tokom koagulacije gvožđe hloridom i optimizacije njihovog kombinovanog uklanjanja. Sagledavanje većeg broja interakcija primenom metodologije odzivne povr&scaron;ine potvrđuje važnost njegove primene pri optimizaciji tretmana vode za piće.</p>

<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>Istraživana je mogućnost primene piljevine različitih vrsta drveta, tehničke celuloze i Kraft lignina kao adsorbenata različitih te&scaron;kih metala iz vode. Za adsorpciju te&scaron;kih metala koji su u vodi prisutni u vidu katjona, kao najbolji adsorbenti su se pokazale piljevine drveta hrasta i bagrema i Kraft lignin. Za adsorpciju hromatnih anjona najbolje su se pokazali Kraft lignin i piljevina drveta jele. Kapacitet adsorpcije piljevine drveta se može pobolj&scaron;ati prethodnim tretiranjem piljevine rastvorom natrijum hidroksida. Efikasnost adsorpcije te&scaron;kih metala iz vode je bolja: kada se primenjuju sitnije čestice piljevine, kada se radi sa većom količinom piljevine i/ili dvostepeno, na povi&scaron;enoj temperaturi. Utvrđen je optimalni pH za adsorpciju pojedinih te&scaron;kih metala, optimalno vreme kontakta adsorbenta i vode, uticaj prisustva različitih te&scaron;kih i lakih metala i anjona na efikasnost adsorpcije te&scaron;kih metala. Adsorbovani te&scaron;ki metali se mogu desorbovati sa piljevine drveta rastvorima različitih mineralnih kiselina. Piljevina drveta se može primeniti u vi&scaron;e ciklusa adsorpcije-desorpcije, uz ne&scaron;to smanjeni kapacitet adsorpcije. Ispitivani adsorbenti se mogu primeniti i u dinamičkim uslovima adsorpcije u koloni.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>The possibility of adsorption of different heavy metals from water by sawdust of different species of wood, pulp, and Kraft lignin has been investigated. Oak and black locust sawdust, and Kraft lignin were shown to be the most efficient adsorbents for heavy metals in cationic form. Kraft lignin and fir sawdust were shown to be the most efficient adsorbents for chromium anions. Previous treatment of wood sawdust by sodium hydroxide solution can increase its adsorption capacity. Better adsorption efficiency was accomplished: when smaller parts of sawdust were used, when a large amount of sawdust was used and/or two stage process was applicated, and adsorption process was done on higher temperature. There were established: optimum initial pH value for different heavy metals, optimum adsorbent - water contact time, and degree of influence of other different heavy and lite metals, and anions on adsorption efficiency. Adsorbed heavy metals can be desorbed from vvood sawdust with solutions of different mineral acids. Sawdust can be applied in several cycles of adsorption - desorption, with some decrease of adsorption capacity. Investigated adsorbents can be also used in dynamic conditions of adsorption in column.</p>

<p>Predmet izučavanja ove disertacije je ispitivanje mogućnosti primene homogenog, heterogenog i Fentonsličnog procesa u tretmanu obojenih otpadnih voda grafičke industrije.&nbsp; Kao Fenton katalizatori kori&scaron;ćeni su sintetisani gvožđe(III)-molibdat i nano nula valentno gvožđe, kao i komercijalni gvožđe(II)-sulfat. Istraživanja&nbsp; su sprovedena u četiri faze. U prvoj fazi&nbsp; je izvr&scaron;ena sinteza&nbsp; i karakterizacija&nbsp; Fenton&nbsp; katalizatora, pri čemu su ustanovljene njihove osnovne morfolo&scaron;ke karakteristike. Nano nula valentno gvožđe je sintetisano iz ekstrakta&nbsp; li&scaron;ća hrasta, dok je&nbsp; gvožđe(III)-molibdat sintetisan putem tzv. vlažnog hemijskog postupka. U drugoj fazi je&nbsp; izvr&scaron;ena optimizacija Fenton procesa u tretmanu sintetičkih rastvora grafičkih&nbsp; boja primenom nove statističke&nbsp; metode,&nbsp;<em> definitive screening design</em>.&nbsp; U&nbsp; cilju postizanja&nbsp; maksimalnog stepena obezbojavanja i mineralizacije tretiranog uzorka&nbsp; ispitan&nbsp; je&nbsp; uticaj&nbsp; sledećih&nbsp; procesnih parametara: inicijalne koncentracije boje, koncentracije gvožđa, pH vrednosti i koncentracije vodonik-peroksida. Nakon ustanovljenih optimalnih uslova i izvr&scaron;ene verifikacije predloženog optimuma, sproveden je tretman realnog efluenta.&nbsp; Stepen mineralizacije&nbsp; tretiranog&nbsp; efluenta&nbsp; ustanovljen&nbsp; je&nbsp; na&nbsp; osnovu&nbsp; vrednosti&nbsp; sadržaja&nbsp; ukupnog&nbsp; organskog&nbsp; ugljenika&nbsp; i&nbsp; hemijske&nbsp; potro&scaron;nje kiseonika.&nbsp; U cilju razumevanja mehanizma degradacije grafičkih boja u Fenton procesu, kao i identifikacije prirode&nbsp; degradacionih&nbsp; produkata,&nbsp; izvr&scaron;ena&nbsp; je&nbsp; kvalitativna&nbsp; gasno-hromatografska/maseno&nbsp; spektrometrijska analiza. Kinetika obezbojavanja realnog&nbsp; efluenta&nbsp; najbolje&nbsp; je opisana primenom&nbsp; Behnajady&nbsp; -&nbsp; Modirshahla&nbsp; -Ghanbary&nbsp; modela,&nbsp; koji&nbsp; defini&scaron;e&nbsp; inicijanu&nbsp; brzinu&nbsp; i&nbsp; oksidacioni&nbsp; kapacitet&nbsp; posmatranog&nbsp; procesa.&nbsp; Rezultati&nbsp; su ukazali&nbsp; na&nbsp; moguću&nbsp; primenu&nbsp; Fenton&nbsp; procesa&nbsp; u&nbsp; tretmanu&nbsp; CMYK&nbsp; boja&nbsp; usled&nbsp; postizanja&nbsp; visokih&nbsp; efikasnosti obezbojavanja i mineralizacije tretiranih efluenata. Nedostatak primenjene metode se ogleda u činjenici da je većina&nbsp; uzoraka&nbsp; okarakterisana&nbsp; kao&nbsp; visoko&nbsp; toksična,&nbsp; a&nbsp; ujedno&nbsp; i&nbsp; izrazito&nbsp; kisela,&nbsp; budući&nbsp; da&nbsp; je&nbsp; ustanovljena optimalna&nbsp; pH&nbsp; vrednost&nbsp; Fenton&nbsp; tretmana&nbsp; 2&nbsp; -&nbsp; 3.&nbsp; Stoga&nbsp; je&nbsp; u&nbsp; okviru&nbsp; treće&nbsp; faze&nbsp; istraživanja&nbsp; primenjen&nbsp; dodatni tretman&nbsp; realnog&nbsp; efluenta,&nbsp; adsorpcija&nbsp; na&nbsp; aktivnom&nbsp; uglju&nbsp; sintetisanom&nbsp; iz&nbsp; ko&scaron;tica&nbsp; divlje&nbsp; &scaron;ljive.&nbsp; Adsorpcioni tretman&nbsp; je rezultovao smanjenjem&nbsp; toksičnosti&nbsp; kod&nbsp; svih tretiranih uzoraka, koji&nbsp; se&nbsp; karakteri&scaron;u&nbsp; kao nisko do umereno toksični, te je sa tog aspekta moguće njihovo bezbedno ispu&scaron;tanje u recipijent. Ujedno je ustanovljena i povećana mineralizacija uzoraka, kao posledica degradacije jedinjenja koja su inicijalno doprinela povećanoj toksičnosti. U četvrtoj fazi rada primenjena je metoda ocenjivanja životnog ciklusa sinteze Fenton katalizatora. Rezultati LCA su utvrdili da sinteza heterogenog Fenton katalizatora, gvožđe(III)-molibdata, ostvaruje najveće opterećenje&nbsp; životne&nbsp; sredine,&nbsp; dok&nbsp; bi&nbsp; se&nbsp; proces&nbsp; sinteze&nbsp; nano&nbsp; nula&nbsp; valentnog&nbsp; gvožđa&nbsp; mogao&nbsp; unaprediti modifikovanjem ekstrakcione faze uz kori&scaron;ćenje alternativnih materijala i obnovljivih izvora energije. Značaj&nbsp; predstavljenih rezultata se ogleda u činjenici da su uzorci obojenih otpadnih voda grafičke industrije prvi put podvrgnuti Fenton tretmanu koji je rezultovao visokim stepenom efikasnosti.</p> / <p>The subject of this thesis is&nbsp; exploring the possibility of homogeneous, heterogeneous and Fenton-like process application in the treatment of dye wastewater in printing industry. Synthesized iron(III)-molybdate and nano zero valent iron, as well as commercial iron(II)-sulfate were used as a Fenton catalyst. The research was carried out in four&nbsp; phases.&nbsp; In&nbsp; the&nbsp; first&nbsp; phase,&nbsp; the&nbsp; catalyst&nbsp; synthesis&nbsp; and&nbsp; their&nbsp; characterization&nbsp; were&nbsp; performed,&nbsp; whereby&nbsp; the morphological characteristics were established. Nano zero valent iron was synthesized from&nbsp; oak leaf extract&nbsp; and iron(III)-molybdate was synthesized by wet chemical process. In the second phase, the optimization of Fenton process was performed within the treatment of synthetic printing dye solution using a new statistical method, a definitive screening design. In order to achieve maximum decolorization and mineralization of the treated sample, the influence of&nbsp; following&nbsp; process parameters was conducted: initial dye concentration, iron concentration, pH value&nbsp; and hydrogen peroxide concentration.&nbsp; The treatment of printing effluent was performed&nbsp; after&nbsp; establishing optimal&nbsp; conditions&nbsp; and&nbsp; verifying&nbsp; the&nbsp; proposed&nbsp; optimum&nbsp; values.&nbsp; Mineralization&nbsp; degree&nbsp; of&nbsp; treated&nbsp; effluent&nbsp; was determined based on the results of total organic carbon and chemical oxygen demand. In order to understand the dye&nbsp; degradation&nbsp; mechanism&nbsp; in&nbsp; Fenton&nbsp; process,&nbsp; as&nbsp; well&nbsp; as&nbsp; to&nbsp; identify&nbsp; degradation&nbsp; products,&nbsp; a&nbsp; qualitative&nbsp; gaschromatographic/mass spectrometric analysis was carried out. The&nbsp; kinetic studies of the printing effluent were best described by using the Behnajady- Modirshahla-Ghanbary model, which defines the initial speed and oxidation capacity of the process. The results indicated the possible application of the Fenton process in the treatment of CMYK dyes due to the high decolorization and mineralization efficiency of treated effluent. Disadvantage of the applied method is reflected in the fact that most of the samples are characterized as highly toxic and,&nbsp; at the same time, extremely acidic since the optimum pH value of Fenton treatment is 2 - 3. Therefore, in the third phase of the study, adsorption process on functionalized biochar prepared from wild plum kernels was applied on real printing effluent.&nbsp; Adsorption&nbsp; treatment&nbsp; resulted&nbsp; in&nbsp; toxicity&nbsp; reduction&nbsp; in&nbsp; all&nbsp; treated&nbsp; samples,&nbsp; characterized&nbsp; as&nbsp; low&nbsp; to moderately toxic. Therefore, from this aspect, treated effluent can be safely released into the recipient. At the same time, increased mineralization of the samples was established as a result of the compounds degradation that initially contributed to high toxicity. In the fourth phase, a life cycle assessment method of Fenton catalyst was applied. The results of the LCA indicated that the synthesis of the heterogeneous Fenton catalyst, iron(III) molybdate, achieved the highest environmental burden, while the synthesis of nano zero valent iron could be improved by modifying the extraction phase using alternative materials and renewable energy sources.&nbsp; The significance of the obtained results is high decolorization efficiency achieved by Fenton treatment of printing dye wastewater,&nbsp; which was used for the first time.</p>

<p>U&nbsp; radu&nbsp; je&nbsp; ispitan&nbsp; uticaj&nbsp; amida&nbsp; kao&nbsp; modela&nbsp; AOM-a (Algalne organske materije)&nbsp; na adsorpciju nitrofenola iz vodene&nbsp; sredine&nbsp; na&nbsp; aktivnom&nbsp; uglju.&nbsp; Istraţivanje&nbsp; se sastojalo&nbsp; iz&nbsp; tri&nbsp; faze:&nbsp; ispitivanje&nbsp; uticaja&nbsp; karateristika amida&nbsp; na&nbsp; adsorpciju&nbsp; nitrofenola,&nbsp; ispitivanje&nbsp; uticaja granulacije na adsorpciju nitrofenola u prisustvu amida i ispitvanje karakterisitka samih nitrofenola na adsorpciju u&nbsp; prisustvu&nbsp; amida.&nbsp; Pre&nbsp; ispitivanja&nbsp; adsorpcije&nbsp; u dvokomponentnim&nbsp; sistemima&nbsp; ispitana&nbsp; je&nbsp; adsorpcija jednokomponentnih&nbsp; sistema&nbsp; 4-nitrofenola,&nbsp; 2,4-dinitrofenola&nbsp; i&nbsp; 2,4,6-trinitrofenola,&nbsp; kao&nbsp; i&nbsp; amida&nbsp; Nmetilbenzamid,&nbsp; nikotinamida&nbsp; i&nbsp; N-benzilbenzamida&nbsp; na komercijalnim&nbsp; aktivnim&nbsp; ugljevima&nbsp; NORIT&nbsp; SA2&nbsp; i&nbsp; dve granulacije&nbsp; aktivnog&nbsp; uglja&nbsp; DARCO.&nbsp; Aktivni&nbsp; ugljevi&nbsp; su ispitani&nbsp; metodom&nbsp; FTIR&nbsp; spektroskopije,&nbsp; SEM&nbsp; analizom, analizom&nbsp; povr&scaron;ine&nbsp; adsorpcijom&nbsp; azota&nbsp; na&nbsp; niskoj temperaturi&nbsp; i&nbsp; određivanjem&nbsp; taĉke&nbsp; nultog&nbsp; naelektrisanja. Urađena&nbsp; je&nbsp; geometrijska&nbsp; optimizacija&nbsp; modela&nbsp; molekula ispitivanih nitrofenola i amida i izraĉunati su molekulski parametri.&nbsp; Uticaj&nbsp; amida&nbsp; kao&nbsp; modela&nbsp; AOM-a&nbsp; je&nbsp; ispitan kori&scaron;ćenjem&nbsp; razliĉitih&nbsp; ravnotežnih&nbsp; i&nbsp; difuzionih adsorpcionih&nbsp; modela.&nbsp; Kao&nbsp; kriterijum&nbsp; za&nbsp; određivanje najsporije&nbsp; adsorpcione&nbsp; faze&nbsp; kori&scaron;ćen&nbsp; je&nbsp; Biotov&nbsp; broj.<br />Adsorpcioni&nbsp; parametri&nbsp; dobijeni&nbsp; u&nbsp; eksperimentima&nbsp; sa dvokomponentnim&nbsp; sistemima&nbsp; su&nbsp; upoređivani&nbsp; sa parametrima dobijenim za adsorpciju samih nitrofenola.</p> / <p>In this research influence of selected amides, as a model of&nbsp; AOM&nbsp; (Algal&nbsp; organic&nbsp; matter),&nbsp; on&nbsp; adsorption&nbsp; of nitrophenols&nbsp; from&nbsp; water&nbsp; on&nbsp; activated&nbsp; carbon&nbsp; has&nbsp; been<br />investigated.&nbsp; Research&nbsp; is&nbsp; divided&nbsp; in&nbsp; three&nbsp; phases: investigation&nbsp; of&nbsp; influence&nbsp; of&nbsp; amide&nbsp; molecule characteristics&nbsp; on&nbsp; the&nbsp; adsorption&nbsp; of&nbsp; nitrophenols, investigation&nbsp; of&nbsp; granulation&nbsp; influence&nbsp; on&nbsp; nitrophenol adsorption in&nbsp; the&nbsp; presence of amide and investigation of nitrophenol characteristics that can influence adsorption in&nbsp; the&nbsp; presence&nbsp; of&nbsp; amides.&nbsp; Adsorption&nbsp; of&nbsp; nitrophenols and&nbsp; amides&nbsp; in&nbsp; single- component&nbsp; systems&nbsp; has&nbsp; also&nbsp; been carried&nbsp; out.&nbsp; Adsorption&nbsp; kinetics&nbsp; of&nbsp; 4-nitrophenol,&nbsp; 2,4-dinitrophenol,&nbsp; 2,4,6-trinitrophenol,&nbsp; N-methylbenzamide,<br />nicotinamide&nbsp; and&nbsp; N-benzylbenzamide&nbsp; has&nbsp; also&nbsp; been investigated. Commercial activated carbons NORIT SA2 and&nbsp; two&nbsp; granulations&nbsp; of&nbsp; DARCO&nbsp; were&nbsp; used.&nbsp; Activated carbons&nbsp; were&nbsp; characterized&nbsp; using&nbsp; FTIR&nbsp; spectroscopy, SEM&nbsp; analysis,&nbsp; internal&nbsp; surface&nbsp; analysis&nbsp; using&nbsp; nitrogen adsorption&nbsp; on&nbsp; low&nbsp; temperature&nbsp; and&nbsp; determination&nbsp; of point&nbsp; of&nbsp; zero&nbsp; charge.&nbsp; Geometry&nbsp; optimization&nbsp; of nitrophenol&nbsp; and&nbsp; amide&nbsp; molecules&nbsp; has&nbsp; been&nbsp; carried&nbsp; out and different molecular parameters have been calculated. Influence&nbsp; of&nbsp; amides&nbsp; as&nbsp; AOM&nbsp; model&nbsp; has&nbsp; been investigated by using diffusion and equilibrium models. Biot number has been obtained&nbsp; in order to establish the limiting&nbsp; step&nbsp; in&nbsp; adsorption&nbsp; process.&nbsp;&nbsp; Adsorption parameters&nbsp; obtained&nbsp; in&nbsp; two-component&nbsp; adsorption systems&nbsp; were&nbsp; compared&nbsp; to&nbsp; parameters&nbsp; obtained&nbsp; for adsorption of nitrophenols alone.</p>

<p>The main goal of the thesis was to prevent the generation of waste, by<br />using the spent coffee grounds (SCG) and date stones (DSAC) for<br />production of activated carbon adsorbent for water treatment. The<br />substances for water removal were selected from those presenting<br />potential risk to aquatic environment according to the NORMAN list of<br />emerging substances and belong to the group of pesticides:<br />carbendazim, linuron and isoproturon. SCG and DSAC adsorbents, as<br />an eco-friendly and low-cost materials, showed high potential for the<br />removal of selected emerging pesticides.</p> / <p>Основни циљ тезе био је смaњeњe стварања отпада коришћењем oтпaдa oд кaфe (SCG) и кoштицa урмe (DSАC) за производњу активног угљa кao адсорбенса за пречишћавање воде. Изaбрaнe супстанце за испитивaњ прoцeсa уклањањa из воде представљају потенцијални ризик за воднe eкo систeмe према NОRМАN листи eмeргeнтних супстaнци и припадају групи пестицида: карбендазим, линурон и изопротурон. SCG и DSАC адсорбенти су, као еколошки прихватљиви материјали нискe цeнe, показали висок потенцијал уклањања одабраних пестицида из aквaтичнoг систeмa.</p> / <p>Osnovni cilj teze bio je smanjenje stvaranja otpada korišćenjem otpada od kafe (SCG) i koštica urme (DSAC) za proizvodnju aktivnog uglja kao adsorbensa za prečišćavanje vode. Izabrane supstance za ispitivanj procesa uklanjanja iz vode predstavljaju potencijalni rizik za vodne eko sisteme prema NORMAN listi emergentnih supstanci i pripadaju grupi pesticida: karbendazim, linuron i izoproturon. SCG i DSAC adsorbenti su, kao ekološki prihvatljivi materijali niske cene, pokazali visok potencijal uklanjanja odabranih pesticida iz akvatičnog sistema.</p>