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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

Étude de la dégradation de molécules organiques complexant des radionucléides par l’utilisation de Procédés d’Oxydation Avancée / Study of the degradation of organic molecules complexing radionuclides by the use of Advanced Oxidation Processes

Rekab, Kamal 23 September 2014 (has links)
Ce travail s'inscrit dans le cadre d'un possible traitement des effluents de Très Faibles Activités (TFA). Parmi ces effluents, certains contiennent du 60Co qui est complexé à des composés organiques tels que l'acide éthylènediaminetétraacétique (EDTA) limitant alors les traitements existants par des méthodes conventionnelles. Ce travail de thèse porte sur l'évaluation de l'efficacité de Procédés d'Oxydation Avancée (UV/H2O2 et UV/TiO2) en vue de dégrader l'EDTA pour libérer le 60Co et ainsi le piéger (par précipitation et/ou adsorption sur des matrices minérales). En effet, l'étude d'adsorption a mis en évidence la capacité du TiO2 à adsorber le cobalt lorsqu'il n'est pas complexé. La précipitation totale du cobalt est quant à elle possible à pH 10 mais peut être réalisée dès pH 9 en présence d'irradiation UV-C. Le flux photonique émis par la lampe a été déterminé par actinométrie chimique et par la méthode de Keitz qui ont données des résultats similaires. L'efficacité des différents procédés pour dégrader l'EDTA et le complexe Co-EDTA a été étudiée en considérant l'influence de plusieurs paramètres (pH, mode d'agitation, type de catalyseur, concentration en H2O2...). Dans leurs conditions optimales, les procédés UV/TiO2 et UV/H2O2 permettent de dégrader et de minéraliser efficacement l'EDTA (composés azotés essentiellement minéralisés en ammonium). Après dégradation du complexe Co-EDTA, il est alors possible de récupérer la totalité du cobalt par adsorption sur le TiO2 et/ou par précipitation. Les procédés ont ensuite été appliqués à un effluent nucléaire contenant du 60Co complexés à des composés organiques. Les POA ont permis d'améliorer de manière significative les facteurs de décontamination en comparaison des méthodes de traitement conventionnelles / This work is part of a possible treatment of effluents of Very Low Level (VLL). Some of these effluents contain 60Co which is complexed with organic compounds such as ethylenediaminetetraacetic acid (EDTA), which limits existing treatments by conventional methods. This PhD work focuses on the evaluation of the efficiency of Advanced Oxidation Processes (UV / H2O2 and UV / TiO2) in order to degrade EDTA to release 60Co and thus trap it (by precipitation and / or adsorption on mineral matrices). Indeed, the adsorption study has demonstrated the ability of TiO2 to adsorb cobalt when it is not complexed. The total precipitation of cobalt is possible at pH 10 but can be performed at pH 9 in the presence of UV-C irradiation. The photon flux emitted by the lamp was determined by chemical actinometry and by the Keitz method which gave similar results. The effectiveness of the various processes to degrade EDTA and the Co-EDTA complex was studied by considering the influence of several parameters (pH, agitation mode, type of catalyst, H2O2 concentration, etc.). Under their optimal conditions, the UV / TiO2 and UV / H2O2 processes can effectively degrade and mineralize EDTA (nitrogen compounds that are essentially mineralized to ammonium). After degradation of the Co-EDTA complex, it is then possible to recover all the cobalt by adsorption on TiO2 and / or by precipitation. The processes were then applied to a nuclear effluent containing 60Co complexed with organic compounds. POAs have significantly improved decontamination factors compared to conventional treatment methods
2

Uticaj oksidacionih procesa na bazi ozona, vodonik-peroksida i UV zračenja na sadržaj i reaktivnost prirodnih organskih materija u vodi / The influence of oxidation processes based on ozone, hydrogen peroxide and UV irradiation on the content and reactivity of natural organic matter in water

Petronijević Mirjana 28 August 2019 (has links)
<p>Cilj&nbsp; istraživanja&nbsp; u&nbsp; okviru&nbsp; ove&nbsp; doktorske&nbsp; disertacije&nbsp; je&nbsp; utvrđivanje&nbsp; efekata&nbsp; različitih<br />oksidacionih procesa na bazi ozona, vodonik-peroksida i UV zračenja na sadržaj i reaktivnost prirodnih&nbsp; organskih&nbsp; materija&nbsp; (POM)&nbsp; u&nbsp; različitim&nbsp; vodenim&nbsp; matriksima.&nbsp; Ispitivanja&nbsp; su sprovedena&nbsp; na&nbsp; a)&nbsp; podzemnoj&nbsp; vodi&nbsp; sa&nbsp; teritorije&nbsp; Kikinde&nbsp; i&nbsp; Temerina&nbsp; (prirodni&nbsp; matriks)&nbsp; i&nbsp; b) sintetičkom&nbsp; vodenom&nbsp; matriksu&nbsp; (rastvoru&nbsp; komercijalno&nbsp; dostupne&nbsp; huminske&nbsp; kiseline),&nbsp; koji&nbsp; se među sobom razlikuju po sastavu i strukturi prisutne POM i sadržaju bromida. Za oksidacioni proces&nbsp; (ozonizacija,&nbsp; UV&nbsp; fotoliza,&nbsp; oksidacija&nbsp; sa&nbsp; H<sub> 2</sub>O<sub>2</sub>,&nbsp; kombinovani&nbsp; O <sub>3 </sub>/UV&nbsp; proces&nbsp; i kombinovani&nbsp; H <sub>2</sub>O<sub>2</sub><br />/UV&nbsp; proces)&nbsp; pojedinačno&nbsp; ispitan&nbsp; je&nbsp; uticaj&nbsp; različitih&nbsp; doza&nbsp; oksidanata&nbsp; i reakcionih&nbsp; uslova.Posebna&nbsp; pažnja&nbsp; posvećena&nbsp; je&nbsp; ispitivanju&nbsp; uticaja&nbsp; navedenih&nbsp; tretmana&nbsp; na<br />formiranje&nbsp; neorganskog&nbsp; bromata,&nbsp; kao&nbsp; i&nbsp; uticaja&nbsp; na&nbsp; sadržaj&nbsp; prekursora&nbsp;&nbsp; dezinfekcionih nusproizvoda nakon hlorisanja (THM, HAA, HAN, HK i CP).<br />Analiza&nbsp; hemijskih&nbsp; parametara&nbsp; sintetičkog&nbsp; matriksa&nbsp; (5,44&plusmn;0,30&nbsp; mg&nbsp; C/l; 0,255&plusmn;0,015 cm<sup> -1</sup> ;&nbsp; 4,68&plusmn;0,41&nbsp; lm<sup> -1</sup> mg <sup>-1 </sup>)&nbsp; pokazuje&nbsp; da&nbsp; u&nbsp; njemu&nbsp; preovladavaju&nbsp; huminnske materije&nbsp; visoke&nbsp; hidrofobnosti.&nbsp; Visok&nbsp; sadržaj&nbsp; POM&nbsp; pretežno&nbsp; hidrofobnog&nbsp; karaktera&nbsp; je zabeležen i u vodi iz Kikinde (5,170,72 mg C/l; 0,2010,001 cm <span id="cke_bm_192S" style="display: none;">&nbsp;</span><span id="cke_bm_190S" style="display: none;">&nbsp;</span><sup>-1</sup><span id="cke_bm_192E" style="display: none;">&nbsp;</span><span id="cke_bm_190E" style="display: none;">&nbsp;</span> ; 3,88&plusmn;0,70 lm<span id="cke_bm_193S" style="display: none;">&nbsp;</span><sup> -1</sup><span id="cke_bm_193E" style="display: none;">&nbsp;</span> mg<sup> -1</sup> ), dok je&nbsp; sadrža<span id="cke_bm_194E" style="display: none;">&nbsp;</span>j&nbsp; POM&nbsp; u&nbsp; sirovoj&nbsp; vodi&nbsp; iz&nbsp; Temerina&nbsp; (2,060,38&nbsp; mg&nbsp; C/l;&nbsp; 0,0500,001&nbsp; cm<span id="cke_bm_203S" style="display: none;">&nbsp;</span><span id="cke_bm_201S" style="display: none;">&nbsp;</span><sup> -1</sup><span id="cke_bm_203E" style="display: none;">&nbsp;</span><span id="cke_bm_201E" style="display: none;">&nbsp;</span>&nbsp; ; 2,43&plusmn;0,21 lm <span id="cke_bm_204S" style="display: none;">&nbsp;</span><sup>-1</sup><span id="cke_bm_204E" style="display: none;">&nbsp;</span> mg <sup>-1</sup><span id="cke_bm_205E" style="display: none;">&nbsp;</span><span id="cke_bm_202E" style="display: none;">&nbsp;</span><span id="cke_bm_191E" style="display: none;">&nbsp;</span><br />) značajno niži i preovladavaju POM hidrofilnog karaktera. Veći stepen hidrofobnosti sintetičkog matriksa u poređenju sa&nbsp; prirodnim matriksima, rezultovao&nbsp; je&nbsp; i&nbsp; većom&nbsp; reaktivnosti&nbsp; organske&nbsp; materije&nbsp; sa&nbsp; hlorom,&nbsp; &scaron;to&nbsp; se&nbsp; može&nbsp; zaključiti&nbsp; na<br />osnovu visokih vrednosti PFDBP nakon hlorisanja. Vrednost PFTHM u sintetičkom matriksu iznosi&nbsp; 544&plusmn;85,9&nbsp; &micro;g/l,&nbsp; dok&nbsp; je&nbsp; PFTHM&nbsp; u&nbsp; kikindskoj&nbsp; i&nbsp; temerinskoj&nbsp; sirovoj&nbsp; vodi&nbsp; znatno&nbsp; niži (279&plusmn;32,3&nbsp; i&nbsp; 180&plusmn;44,0&nbsp; &micro;g/l,&nbsp; respektivno).&nbsp; Vrednost&nbsp; PFHAA&nbsp; u&nbsp; sintetičkom&nbsp; matriksu&nbsp; iznosi 484&plusmn;77,5 &micro;g/l, dok je PFHAA u kikindskoj 244&plusmn;11,1 &micro;g/l i u temerinskoj vodi 165&plusmn;32,5 &micro;g/l. Sadržaj&nbsp; HK&nbsp; (8,05&plusmn;3,63&nbsp; &micro;g/l&nbsp; sintetički&nbsp; matriks;&nbsp; 14,91,38&nbsp; &micro;g/l&nbsp; Kikinda;&nbsp; 7,400,25&nbsp; &micro;g/l Temerin)&nbsp; je&nbsp; znatno&nbsp; niži&nbsp; u&nbsp; poređenju&nbsp; sa&nbsp; prekursorima&nbsp; THM&nbsp; i&nbsp; HAA,&nbsp; dok&nbsp; prekursori&nbsp; HAN&nbsp; i hlorpikrina&nbsp; nisu&nbsp; detektovani&nbsp; u&nbsp; sirovoj&nbsp; vodi.&nbsp; Nusproizvodi&nbsp; koji&nbsp; se&nbsp; dominantno&nbsp; formiraju&nbsp; u svim&nbsp; ispitivanim&nbsp; vodenim&nbsp; matriksima&nbsp; su&nbsp; hlorovani&nbsp; THM&nbsp; i&nbsp; HAA,&nbsp; dok&nbsp; se&nbsp; bromovani&nbsp; DBPformiraju u znatno nižim koncentracijama. Zastupljenost bromovanih DBP u temerinskoj vodi<br />je&nbsp; znatno&nbsp; veći&nbsp; u&nbsp; poređenju&nbsp; sa&nbsp; vodom&nbsp; iz&nbsp; Kikinde,&nbsp; kao&nbsp; rezultat&nbsp; prisustva&nbsp; veće&nbsp; koncentracije bromida u sirovoj vodi (0,05&plusmn;0,01 mg Br -/l Temerin; 0,03&plusmn;0,01 mg Br<br />-/l Kikinda). Ispitivanjem&nbsp; uticaja&nbsp; oksidacionih&nbsp; procesa&nbsp; (UV&nbsp; fotolize,&nbsp; ozonizacije,&nbsp; oksidacije vodonik-peroksidom)&nbsp; na&nbsp; sadržaj&nbsp; i&nbsp; reaktivnost&nbsp; POM&nbsp; u&nbsp; ispitivanim&nbsp; vodenim&nbsp; matriksima utvrđeno&nbsp; je&nbsp; da&nbsp; tretman&nbsp; vode&nbsp; UV&nbsp; zračenjem&nbsp; i&nbsp; vodonik-peroksidom,&nbsp; kada&nbsp; se&nbsp; primenjuju&nbsp; kao samostalan&nbsp; tretman,&nbsp; ne&nbsp; pokazuju&nbsp; značajnu&nbsp; efikasnost&nbsp; u&nbsp; smanjenju&nbsp; sadržaja&nbsp; POM.Tretman vode&nbsp; ozonom&nbsp; se&nbsp; pokazao&nbsp; kao&nbsp; veoma&nbsp; efikasan&nbsp; u&nbsp; uklanjanju&nbsp; POM&nbsp; i&nbsp; u&nbsp; smanjenju&nbsp; sadržaja prekursora&nbsp; DBP&nbsp; kod&nbsp; svih&nbsp; ispitivanih&nbsp; vodenih&nbsp; matriksa,&nbsp; kao&nbsp; rezultat&nbsp; smanjenja&nbsp; reaktivnosti POM&nbsp; ka&nbsp; formiranju&nbsp; ovih&nbsp; DBP.&nbsp; Smanjenje&nbsp; sadržaja&nbsp; POM&nbsp; u&nbsp; vodi&nbsp; tokom&nbsp; tretmana&nbsp; raste&nbsp; sa povećanjem&nbsp; primenjene&nbsp; doze&nbsp; ozona,&nbsp; pri&nbsp; čemu&nbsp; se&nbsp; najbolji&nbsp; rezultati&nbsp; postižu&nbsp; pri&nbsp; najvećoj primenjenoj&nbsp; dozi&nbsp; od&nbsp; 3,0&nbsp; mg&nbsp; O 3/mg&nbsp; DOC&nbsp; (do&nbsp; 32%&nbsp; DOC,&nbsp; 92%&nbsp; UV254 sintetički&nbsp; matriks;&nbsp; do 17%&nbsp; DOC,&nbsp; 76%&nbsp; UV 254&nbsp; Kikinda;&nbsp; do&nbsp; 15%&nbsp; DOC&nbsp; i&nbsp; 66%&nbsp; UV254&nbsp;&nbsp;&nbsp; Temerin).&nbsp; U&nbsp; sintetičkom matriksu&nbsp; najveće&nbsp; smanjenje&nbsp; PFTHM&nbsp; (za&nbsp; 76%)&nbsp; i&nbsp; PFHAA&nbsp; (za&nbsp; 80%)&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; sadržaj&nbsp; u sirovoj vodi se postiže pri dozi od 1,0&nbsp; mg O<sub>3 </sub>/mg DOC. Najveće smanjenje PFTHM (za 38%)<br />i PFHAA (za 42%) u vodi iz Kikinde postiže se pri dozi od 3,0 mg O <sub>3 </sub>/mg DOC. U vodi iz Temerina najveće smanjenje PFTHM (za&nbsp; 27%) je pri dozi od 3,0 mg O <sub>3</sub> /mg DOC, dok se za smnjenje&nbsp; PFHAA&nbsp; (za&nbsp; 54%)&nbsp; najbolje&nbsp; pokazala&nbsp; doza&nbsp; od&nbsp; 1,0&nbsp; mg&nbsp; O<br />3 /mg&nbsp; DOC.&nbsp; Sadržaj prekursora&nbsp; HK&nbsp; i&nbsp; HAN&nbsp; (temerinska&nbsp; voda)&nbsp; je&nbsp; veoma&nbsp; nizak&nbsp; nakon&nbsp; tretmana.&nbsp; Tretman&nbsp; vode ozonom&nbsp; vodi&nbsp; ka&nbsp; formiranju&nbsp; DBP&nbsp; sa&nbsp; vi&scaron;e&nbsp;&nbsp; supstituisanih&nbsp; atoma&nbsp; broma,&nbsp; dok&nbsp; u&nbsp; vodama&nbsp; sa srednjim sadržajem bromida (50 &micro;g Br -/l) dovodi do formiranja bromata. Kombinacijom&nbsp; ozonizacije&nbsp; sa&nbsp; UV&nbsp; zračenjem&nbsp; se&nbsp; značajno&nbsp; može&nbsp; pospe&scaron;iti&nbsp; efiksnost uklanjanja&nbsp; POM&nbsp; postignuta&nbsp; primenom&nbsp; samostalne&nbsp; ozonizacije.&nbsp; Najveće&nbsp; smanjenje&nbsp; sadržaja POM u&nbsp; sintetičkom matriksu (za 85% DOC, 98% UV254 i 87% SUVA), u vodi iz Kikinde (za<br />23% DOC, 83% UV 254, 77% SUVA), i vodi iz Temerina (za 15% DOC, 80% UV<br />254 i 75% SUVA), u odnosu na vrednosti u netretiranoj vodi postignuto je pri najvećoj primenjenoj dozi od&nbsp; 3,0&nbsp; mg&nbsp; O<sub> 3</sub> /mg&nbsp; DOC&nbsp; i&nbsp; 6000&nbsp; mJ/cm 2 .&nbsp; Efikasnost&nbsp; procesa&nbsp; raste&nbsp; u&nbsp; vodama&nbsp; u&nbsp; kojima preovladavaju&nbsp; POM&nbsp; veće&nbsp; hidrofobnosti.&nbsp; MeĎutim,&nbsp; iako&nbsp; se&nbsp; O<sub> 3</sub> /UV&nbsp; procesom&nbsp; postiže&nbsp; visok stepen&nbsp; smanjenja&nbsp; PFTHM&nbsp; u&nbsp; sintetičkom&nbsp; matriksu&nbsp; se&nbsp; najbolje&nbsp; pokazao&nbsp; tretman&nbsp; ozonom (1,0 mg&nbsp; O3/mg&nbsp; DOC),&nbsp; dok&nbsp; se&nbsp; najveće&nbsp; smanjenje&nbsp; PFHAA&nbsp; (82%)&nbsp; postiže&nbsp; pri&nbsp; dozi&nbsp; ozona&nbsp; od 1,0 mg O<sub>3/</sub>mg DOC i UV zračenja od 6000 mJ/cm <sup>2 .</sup> U vodi iz Kikinde se PFTHM smanjuje za 50% pri dozi od 3,0 mg O <sub>3</sub>/mg DOC i 6000 mJ/cm 2 , dok se u slučaju uklanjanja prekursora<br />HAA&nbsp; ozonizacija&nbsp; pokazala&nbsp; kao&nbsp; superiorniji&nbsp; proces.&nbsp; U&nbsp; vodi&nbsp; iz&nbsp; Temerina&nbsp; se&nbsp; u&nbsp; pogledu uklanjanja&nbsp; prekursora&nbsp; THM&nbsp; i&nbsp; HAA&nbsp; ozonizacija&nbsp; pokazala&nbsp; kao&nbsp; optimalan&nbsp; proces.&nbsp; Visok alkalitet&nbsp; prirodnih&nbsp; voda&nbsp; inhibira&nbsp; radikalski&nbsp; mehanizam&nbsp; u&nbsp; toku&nbsp; AOP&nbsp; i&nbsp; favorizuje&nbsp; oksidaciju POM molekulskim ozonom.&nbsp; Prekursori HK se formiraju u&nbsp; veoma niskim koncentracijama i njihov sadržaj ne varira značajno tokom tretmana. U prirodnim matriksima tokom AOP pri dozi&nbsp; ozona&nbsp; od&nbsp; 3,0 mg&nbsp; O<sub>3</sub> /mg&nbsp; DOC&nbsp; dolazi&nbsp; do&nbsp; formiranja&nbsp; HAN,&nbsp; međutim,&nbsp; nije&nbsp; uočen&nbsp; jasan trend&nbsp; sa&nbsp; povećanjem&nbsp; doze&nbsp; UV&nbsp; zračenja.&nbsp; Tretman&nbsp; doprinosi&nbsp; formiranju&nbsp; bromovanih&nbsp; vrsta THM,&nbsp; dok&nbsp; se&nbsp; tokom&nbsp; AOP&nbsp; pri&nbsp; najvećoj&nbsp; dozi&nbsp; ozona&nbsp; od&nbsp; 3,0 mg&nbsp; O<sub>3</sub> /mg&nbsp; DOC&nbsp; formiraju bromovani HAN.<br />Najveće&nbsp; smanjenje&nbsp; sadržaja&nbsp; POM&nbsp; primenom&nbsp; kombinacije&nbsp; oksidacije&nbsp; sa&nbsp; H <sub>2</sub>O<sub>2</sub><br />i&nbsp; UV zračenja u sintetičkom matriksu (za do 17% DOC, 70% UV 254 ), u vodi iz Kikinde (za do 22% DOC, 53% UV<sub>254</sub>), i vodi iz Temerina (za do 7% DOC, 68% UV<br /><sub>254 </sub>), u odnosu na vrednosti u sirovoj vodi, se postižu pri dozi H <sub>2</sub>O<sub>2</sub> i UV zračenja od 3,0 mg H<sub>2</sub>O<sub>2</sub>/mg DOC i 6000 mJ/cm <sup>2</sup> .<br />Najveće&nbsp; smanjenje&nbsp; PFTHM&nbsp; od&nbsp; 54%&nbsp; u&nbsp; sintetičkom&nbsp; matriksu&nbsp; se&nbsp; postiže&nbsp; pri&nbsp; dozi&nbsp; od 0 mg H<sub>2</sub>O<sub>2</sub>/mg DOC i 6000 mJ/cm <sup>2</sup> ,&nbsp; dok se smanjenje PFHAA (za 35%)&nbsp; postiže primenom doze vodonik-peroksida i UV zračenja od 1,0 mg H <sub>2</sub>O<sub>2</sub> /mg&nbsp; DOC i 3000 mJ/cm <sup>2</sup> . U vodi izKikinde&nbsp; H<sub>2</sub>O<sub>2</sub> /UV&nbsp; proces&nbsp; ne&nbsp; utiče&nbsp; značajno&nbsp; na&nbsp; sadržaj&nbsp; prekursora&nbsp; THM,&nbsp; dok&nbsp; se&nbsp; najveće smanjenje&nbsp; PFHAA&nbsp; (za&nbsp; 35%)&nbsp; postiže&nbsp; pri&nbsp; dozi&nbsp; od&nbsp; 3,0&nbsp; mg&nbsp; H<sub> <span id="cke_bm_235S" style="display: none;">&nbsp;</span>2<span id="cke_bm_235E" style="display: none;">&nbsp;</span></sub>O<sub>2</sub>/mg&nbsp; DOC&nbsp; i&nbsp; 600&nbsp; mJ/cm <sup>2</sup> .H<span id="cke_bm_184S" style="display: none;">&nbsp;</span><sub>2</sub><span id="cke_bm_184E" style="display: none;">&nbsp;</span>O<sub>2</sub><span id="cke_bm_185E" style="display: none;">&nbsp;</span>/UV&nbsp; proces&nbsp; dovodi&nbsp; do&nbsp; smanjenja&nbsp; PFTHM&nbsp; u&nbsp; Temerinskoj&nbsp; vodi&nbsp; za&nbsp; 74%&nbsp; pri&nbsp; dozi&nbsp; od 3,0 mg H<sub>2</sub>O<sub>2</sub>/mg DOC i 600 mJ/c<span id="cke_bm_236E" style="display: none;">&nbsp;</span>m <sup>2</sup> ,&nbsp; dok primenjeni tretman ne pokazuje značajan uticaj na<br />PFHAA.&nbsp; Prekursori HK su detektovani u sintetičkom matriksu i temerinskoj vodi u niskim koncentracijama.&nbsp; U&nbsp; temerinskoj&nbsp; vodi&nbsp; nakon&nbsp; AOP&nbsp; pri&nbsp; dozi&nbsp; vodonik-peroksida&nbsp; od 3,0 mg H<sub>2</sub>O<sub>2</sub> /mg DOC dolazi&nbsp; do formiranja HAN i hlorpikrina. Primenjeni tretman vodi ka formiranju bromovanih DBP. Svi rezultati dobijeni u toku istraživanja ukazuju na neophodnost optimizacije procesa u&nbsp; tretmanu&nbsp; ispitivanih&nbsp; vodenih&nbsp; matriksa&nbsp; i&nbsp; određivanja&nbsp; optimalnog&nbsp; procesa uzimajući&nbsp; u&nbsp; obzir<br />karakteristika&nbsp; sirove&nbsp; vode&nbsp; i&nbsp; efikasnost&nbsp; koja&nbsp; se&nbsp; želi&nbsp; postići.Kombinacijom&nbsp; dva&nbsp; i&nbsp; vi&scaron;e konvencionalnih&nbsp; tretmana&nbsp; i&nbsp; optimizacijom&nbsp; reakcionih&nbsp; uslova&nbsp; može&nbsp; se&nbsp; postići&nbsp; visoka efikasnost uklanjanja POM, kao i ciljano uklanjanje prekursorskog materijala odabranih DBP, međutim&nbsp; tretman&nbsp; vode&nbsp; ozonom&nbsp; pri&nbsp; dozi&nbsp; od&nbsp; 1,0 mg&nbsp; O<sub>3</sub><br />/mg&nbsp; DOC&nbsp; se&nbsp; pokazao&nbsp; kao&nbsp; optimalan proces.</p> / <p>The aim of the research&nbsp; of&nbsp; this&nbsp; PhD thesis&nbsp; was&nbsp; to determine the effects of various oxidation processes based on ozone, hydrogen peroxide and UV irradiation on the content and reactivity of natural organic matter&nbsp; (NOM)&nbsp; in different water matrices. The&nbsp; tests were carried out&nbsp; on&nbsp; a)&nbsp; groundwater&nbsp; from&nbsp; the&nbsp; territory&nbsp; of&nbsp; Kikinda&nbsp; and&nbsp; Temerin&nbsp; (natural&nbsp; matrix)&nbsp; and&nbsp; b) synthetic aqueous matrix (solution of commercially available humic&nbsp; acid), which differ in the composition&nbsp; and&nbsp; structure&nbsp; of&nbsp; NOM&nbsp; present&nbsp; and&nbsp; the&nbsp; content&nbsp; of&nbsp; bromide.&nbsp; For&nbsp; the&nbsp; oxidation process&nbsp; (ozonation,&nbsp; UV&nbsp; photolysis,&nbsp; oxidation&nbsp; with&nbsp; H 2O2 ,&nbsp; combined&nbsp; O 3 /UV&nbsp; process&nbsp; and combined&nbsp; H 2O2 /UV&nbsp; process),&nbsp; the&nbsp; influence&nbsp; of&nbsp; different&nbsp; doses&nbsp; of&nbsp; oxidants&nbsp; and&nbsp; reaction conditions&nbsp; was&nbsp; examined&nbsp; individually.&nbsp; Particular&nbsp; attention&nbsp; was&nbsp; paid&nbsp; to&nbsp; the&nbsp; influence&nbsp; of&nbsp; the above treatment on the formation of inorganic bromate, as well as the effect on the content of precursors of disinfectant by-products after chlorination (THM, HAA, HAN, HK and CP).Analysis&nbsp; of&nbsp; the&nbsp; chemical&nbsp; parameters&nbsp; of&nbsp; the&nbsp; synthetic&nbsp; matrix&nbsp; (5.44&plusmn;0.30&nbsp; mg&nbsp; C/L; 0.255&plusmn;0.015 cm -1 ;&nbsp; 4.68&plusmn;0.41&nbsp; lm -1 mg -1 )&nbsp; shows&nbsp; that&nbsp; the&nbsp; high-hydrophobic&nbsp; humic&nbsp; compounds predominate in this water. Also, high NOM content of predominantly hydrophobic character was recorded in Kikinda water (5.170.72 mg C/L; 0.2010.001 cm -1 ;&nbsp; 3.88&plusmn;0.70 lm -1 mg -1 ), while&nbsp; NOM&nbsp; content&nbsp; in&nbsp; raw&nbsp; water&nbsp; from&nbsp; Temerin&nbsp; (2.060.38&nbsp; mg&nbsp; C/L;&nbsp; 0.0500.001&nbsp; cm -1 ; 2.43&plusmn;0.21 lm -1 mg -1 ) significantly lower and predominate NOM of hydrophilic character. A higher degree of hydrophobicity of the synthetic matrix in comparison with&nbsp; natural matrices, resulted in higher reactivity of organic matter with chlorine, which can be concluded on&nbsp; the&nbsp; basis&nbsp; of&nbsp; high&nbsp; PFDBP&nbsp; values&nbsp; after&nbsp; chlorination.&nbsp; The&nbsp; PFTHM&nbsp; value&nbsp; in&nbsp; the&nbsp; synthetic matrix&nbsp; was&nbsp; 544&plusmn;85.9 &micro;g/L, while the PFTHM in the raw waters from Kikinda and Temerin was&nbsp; significantly&nbsp; lower&nbsp; (279&plusmn;32.3&nbsp; and&nbsp; 180&plusmn;44.0&nbsp; &micro;g/L,&nbsp; respectively).&nbsp; The&nbsp; PFHAA&nbsp; value&nbsp; in the&nbsp; synthetic&nbsp; matrix&nbsp; was&nbsp; 484&plusmn;77.5&nbsp; &micro;g/L,&nbsp; while&nbsp; PFHAA&nbsp; in&nbsp; the&nbsp; Kikinda&nbsp; water&nbsp; was 223 244&plusmn;11.1 &micro;g/L&nbsp; and in&nbsp; the&nbsp; Temerin&nbsp; water&nbsp; was&nbsp; 165&plusmn;32.5 &micro;g/L.&nbsp; The content of&nbsp; precursors of HK&nbsp; (8.05&plusmn;3.63&nbsp; &micro;g/L&nbsp; synthetic&nbsp; matrix;&nbsp; 14.91.38&nbsp; &micro;g/L&nbsp; Kikinda;&nbsp; 7.400.25&nbsp; &micro;g/L&nbsp; Temerin) was&nbsp; significantly&nbsp; lower&nbsp; compared&nbsp; to&nbsp; precursors&nbsp; of&nbsp; THMs&nbsp; and&nbsp; HAAs,&nbsp; while&nbsp; precursors&nbsp; of HANs&nbsp; and&nbsp; chloropicrin&nbsp; were&nbsp; not&nbsp; detected&nbsp; in&nbsp; raw&nbsp; water.&nbsp; The&nbsp; by- products&nbsp; that&nbsp; were predominantly&nbsp; formed&nbsp; in&nbsp; all&nbsp; the&nbsp; tested&nbsp; water&nbsp; matrices&nbsp; were&nbsp; chlorinated&nbsp; THMs&nbsp; and&nbsp; HAAs, while the brominated DBPs&nbsp; were&nbsp; formed at substantially lower concentrations. The presence of&nbsp; brominated DBPs&nbsp; in&nbsp; Temerine&nbsp; water&nbsp; were&nbsp; significantly higher compared to Kikinda water as&nbsp; a&nbsp; result&nbsp; of&nbsp; the&nbsp; presence&nbsp; of&nbsp; higher&nbsp; bromide&nbsp; content&nbsp; in&nbsp; raw&nbsp; water&nbsp; (0.05&plusmn;0.01&nbsp; mg&nbsp; Br -/L Temerin; 0.03&plusmn;0.01 mg Br -/L Kikinda). By&nbsp; examining&nbsp; the&nbsp; influence&nbsp; of&nbsp; oxidation&nbsp; processes&nbsp; (UV&nbsp; photolysis,&nbsp; ozonation,hydrogen&nbsp; peroxide&nbsp; oxidation)&nbsp; on&nbsp; the&nbsp; content&nbsp; and&nbsp; reactivity&nbsp; of&nbsp; NOM&nbsp; in&nbsp; the&nbsp; tested&nbsp; water matrix, it was&nbsp; found that the UV&nbsp; irradiation and&nbsp; treatment by&nbsp; hydrogen peroxide, when used as an independent treatment, did&nbsp; not show significant efficacy in reducing the&nbsp; NOM content. Water treatment by ozone&nbsp; proved to be very effective in eliminating&nbsp; NOM and reducing the content of DBP precursors in all tested water&nbsp; matrices, as a result of the reduction of&nbsp; NOM reactivity &nbsp; to&nbsp; the&nbsp; formation&nbsp; of&nbsp; these&nbsp; DBPs.&nbsp; Reduction&nbsp; of&nbsp; NOM&nbsp; content&nbsp; in&nbsp; water&nbsp; during treatment increased&nbsp; with increasing the applied dose of ozone, with the best results achieved at the highest dosage of&nbsp; 3.0 mg O 3/mg DOC&nbsp; (up to 32% DOC, 92% UV 254&nbsp; synthetic matrix, up&nbsp; to&nbsp; 17%&nbsp; DOC,&nbsp; 76%&nbsp; UV 254 Kikinda,&nbsp; up&nbsp; to&nbsp; 15%&nbsp; DOC&nbsp; and&nbsp; 66%&nbsp; UV254 Temerin).&nbsp; In&nbsp; the synthetic&nbsp; matrix the highest reduction&nbsp; in&nbsp; PFTHM (76%) and PFHAA (by 80%)&nbsp; compared to raw water content&nbsp; was&nbsp; achieved at a dosage&nbsp; of 1.0 mg O 3/mg DOC. The highest reduction in PFTHM&nbsp; (38%)&nbsp; and&nbsp; PFHAA&nbsp; (42%)&nbsp; in&nbsp; Kikinda&nbsp; water&nbsp; was&nbsp; achieved&nbsp; at&nbsp; a&nbsp; dose&nbsp; of 3.0 mg O3 /mg DOC. In Temerin water, the highest reduction in PFTHM (27%) was at a dose of&nbsp; 3.0 mg O 3/mg DOC, while the dose of 1.0&nbsp; mg O3 /mg&nbsp; DOC&nbsp; was best shown for removing PFHAA (by 54%). The content of the precursors of HKs and HANs (Temerin water) was very low&nbsp; after&nbsp; treatment.&nbsp; Water&nbsp; treatment&nbsp; by&nbsp; ozone&nbsp; led&nbsp; to&nbsp; the&nbsp; formation&nbsp; of&nbsp; DBPs&nbsp; with&nbsp; more substituted bromine atoms, while in waters with a mean bromide content (50 &mu;g Br -/L) led&nbsp; to bromate formation.Combination of ozonation with UV irradiation can greatly accelerate the effectiveness of&nbsp; NOM&nbsp; removal&nbsp; achieved&nbsp; by&nbsp; the&nbsp; use&nbsp; of&nbsp; ozonation&nbsp; alone.&nbsp; The&nbsp; highest&nbsp; reduction&nbsp; in&nbsp; NOM content in the synthetic matrix (by 85% DOC, 98% UV 254 and 87% SUVA), in Kikinda water (by 23%&nbsp; DOC, 83% UV 254 , 77% SUVA) and water from Temerin (by 15% DOC, 80% UV 254 and 75% SUVA), compared to the values in&nbsp; raw&nbsp; water, was achieved at the highest&nbsp; dose of 3.0&nbsp; mg&nbsp; O 3 /mg&nbsp; DOC&nbsp; and&nbsp; 6000&nbsp; mJ/cm 2 .&nbsp; The&nbsp; efficiency&nbsp; of&nbsp; the&nbsp; process&nbsp; was&nbsp; growing&nbsp; in&nbsp; the waters where NOM predominates of hydrophobicity. Although the O 3 /UV process achieved a high&nbsp; degree&nbsp; of&nbsp; reduction&nbsp; in&nbsp; PFTHM&nbsp; in&nbsp; the&nbsp; synthetic&nbsp; matrix&nbsp; the&nbsp; ozonation (1.0 mg O3 /mg DOC)&nbsp; was&nbsp; proved&nbsp; as&nbsp; more&nbsp; efficient,&nbsp; while&nbsp; the&nbsp; highest&nbsp; reduction&nbsp; in&nbsp; PFHAA (82%)&nbsp; was&nbsp; achieved&nbsp; at&nbsp; a&nbsp; ozone&nbsp; dose&nbsp; of&nbsp; 1.0&nbsp; mg&nbsp; O 3/mg&nbsp; DOC&nbsp; and&nbsp; UV&nbsp; irradiation&nbsp; of 6000 mJ/cm 2 . In the water from Temerin,&nbsp; in case to removal of precursors of THM and HAA, ozonation&nbsp; was proved&nbsp; to be an optimal process. High alkalinity of natural waters&nbsp; inhibits the radical &nbsp; mechanism&nbsp; during&nbsp; AOP&nbsp; and&nbsp; favors&nbsp; NOM&nbsp; oxidation&nbsp; with&nbsp; molecular&nbsp; ozone.&nbsp; HKs precursors were formed at very low concentrations and their content did not vary significantly during&nbsp; the&nbsp; treatment.&nbsp; In&nbsp; natural&nbsp; matrices&nbsp; during&nbsp; the&nbsp; AOP&nbsp; at&nbsp; a&nbsp; ozone&nbsp;&nbsp; dose&nbsp; of 3.0 mg O3 /mgDOC, HANs&nbsp; were&nbsp; formed, however, there&nbsp; was&nbsp; no clear trend with increasing UV irradiation. The treatment contributed to the formation of brominated THM species, while during&nbsp; the&nbsp; AOPs,&nbsp; brominated&nbsp; HANs&nbsp; were&nbsp; formed&nbsp; at&nbsp; the&nbsp; maximum&nbsp; dose&nbsp; of&nbsp; ozone&nbsp; of 3.0 mg O3/mg DOC. 224 The largest decrease in&nbsp; NOM content by the combination of oxidation with H2O2 and UV irradiation in the synthetic matrix (for up to 17% DOC, 70% UV 254 ), in Kikinda water (up to 22% DOC, 53% UV 254), and water from Temerin&nbsp; (7% DOC, 68% UV 254 ), compared&nbsp; to the values&nbsp; in&nbsp; raw&nbsp; water,&nbsp; were&nbsp; obtained&nbsp; at&nbsp; a&nbsp; dose&nbsp; of&nbsp; H 2O2 and&nbsp; UV&nbsp; irradiation&nbsp; of 3.0 mg O3 /mg DOC&nbsp; and 6000 mJ/cm 2 . The highest PFTHM reduction of 54% in the&nbsp; synthetic matrix was achieved at a dosage of 1.0 mg H2O2/mg DOC and 6000 mJ/cm 2 , while a decrease in&nbsp; PFHAA&nbsp; (35%)&nbsp; was&nbsp; achieved&nbsp; using&nbsp; a&nbsp; dose&nbsp; of&nbsp; hydrogen&nbsp; peroxide&nbsp; and&nbsp; UV&nbsp; irradiation&nbsp; of 1.0 mg H2O2/mg DOC and 3000 mJ/cm 2 . In the water from Kikinda, the H2O2 /UV process did not significantly affect on the THM precursors content, while the highest reduction in PFHAA (35%)&nbsp; was&nbsp; achieved&nbsp; at&nbsp; a&nbsp; dose&nbsp; of&nbsp; 3.0&nbsp; mg&nbsp; H2O2/mg&nbsp; DOC&nbsp; and&nbsp; 600&nbsp; mJ/cm 2 .&nbsp; The&nbsp; H 2O2 /UV process&nbsp; led&nbsp; to&nbsp; a&nbsp; decrease&nbsp; in&nbsp; PFTHM&nbsp; in&nbsp; the&nbsp; Temerin&nbsp; water&nbsp; by&nbsp; 74%&nbsp; at&nbsp; a&nbsp; dose&nbsp; of 3.0 mg&nbsp; 2O2 /mg&nbsp; DOC&nbsp; and&nbsp; 600&nbsp; mJ/cm 2 ,&nbsp; whereas&nbsp; the&nbsp; treatment&nbsp; applied&nbsp; had&nbsp; no&nbsp; significant effect on PFHAA. HKs precursors were detected in synthetic matrix and the Temerin water at low&nbsp; concentrations.&nbsp; In&nbsp; the&nbsp; water&nbsp; after&nbsp; the&nbsp; AOP&nbsp; at&nbsp; a&nbsp; dose&nbsp; of&nbsp; 3.0&nbsp; mg&nbsp; H 2O2 /mg&nbsp; DOC&nbsp; of hydrogen&nbsp; peroxide,&nbsp; HANs&nbsp; and&nbsp; chloropicrin&nbsp; were&nbsp; formed.&nbsp; The&nbsp; applied&nbsp; treatment&nbsp; led&nbsp; to&nbsp; the formation of brominated DBPs.<br />All the results obtained during the research indicate the necessity of optimization&nbsp; the process&nbsp; in&nbsp; the&nbsp; treatment&nbsp; of&nbsp; the&nbsp; examined&nbsp; water&nbsp; matrices&nbsp; and&nbsp; determination&nbsp; of&nbsp; the&nbsp; optimal process taking into account the characteristics of&nbsp; raw water and the efficiency to be achieved. By combining two or more conventional treatments and optimizing the reaction conditions, high&nbsp; NOM removal efficiency can be achieved, as well as removal of the&nbsp; targeted&nbsp; precursor material&nbsp; of&nbsp; the&nbsp; selected&nbsp; DBPs,&nbsp; but&nbsp; the&nbsp; treatment&nbsp; of&nbsp; ozone&nbsp; water&nbsp; at&nbsp; a&nbsp; dose&nbsp; of 1.0 mg O3 /mg DOC was proved to be an optimal process.</p>

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