A presença de antibióticos no ecossistema representa um sério risco à saúde humana e animal em virtude do desenvolvimento crescente de resistência bacteriana. Uma vez que a maioria dos antibióticos é persistente à degradação biológica, os processos oxidativos avançados são apontados como uma das tecnologias mais efetivas para decompor esses compostos em águas residuárias. A bacitracina zíncica (Bc-Zn) é um potente antibiótico constituído por uma mistura complexa de peptídeos não-biodegradáveis, conjugados ao zinco. Apesar de ser um antibiótico amplamente consumido na medicina humana e animal, é preocupante a escassez de estudos que investigam sua degradação e destino ambiental. O presente trabalho analisou a degradação da Bc-Zn através dos processos de fotólise direta e UV/H2O2 em diferentes condições de radiação UVC e concentração inicial de H2O2. Os parâmetros cinéticos rendimento quântico da fotólise, constantes cinéticas de pseudo-primeira ordem e constante cinéticas de segunda ordem foram satisfatoriamente estimados pela modelagem do sistema fotoquímico experimental. Os resultados revelaram que a fotólise direta permitiu degradar todos os congêneres da mistura de Bc-Zn nas maiores doses de radiação UVC empregadas. No entanto, não houve remoção de TOC após 120 minutos de irradiação. A adição de H2O2 acelerou substancialmente a fotodegradação do antibiótico, apresentando constantes cinéticas de pseudo-primeira ordem uma ordem de grandeza superiores às obtidas por fotólise direta. Além disso, remoção considerável de até 71% do TOC foi alcançada. A análise estatística demonstrou que a radiação UV foi um fator bem mais significativo para a fotodegradação da Bc-Zn em relação à concentração inicial de H2O2, sendo as melhores condições do processo alcançadas para a maior taxa específica de emissão de fótons (1,11×10-5 Einstein L-1 s-1). Ensaios biológicos com soluções tratadas por fotólise direta e UV/H2O2 indicaram remoção completa da atividade antimicrobiana residual, ainda que os produtos da fotodegradação tenham se mostrado não-biodegradáveis. Análises de toxicidade indicaram que o metal zinco presente no antibiótico é responsável pela a toxicidade no micro-organismo-teste Vibrio fischeri. Estudos adicionais devem ser realizados para identificar os sub-produtos formados, bem como para investigar a degradação da Bc-Zn em efluentes industriais reais. / The presence of antibiotics in ecosystems represents a serious risk to human and animal health, caused by the increase in bacterial resistance. Since most antibiotics resist to biological degradation, advanced oxidation processes are pointed out as the most effective technologies for degrading these compounds in wastewater. Zinc bacitracin (Bc-Zn) is a potent antibiotic with a complex mixture of non-biodegradable peptides conjugated to zinc. Despite being a widely used antibiotic in human and animal medicine, the scarcity of studies dealing with its degradation and environmental fate is a matter of concern. In this work, Bc-Zn degradation by direct photolysis and the UV/H2O2 process was investigated for different UVC radiation conditions and initial H2O2 concentrations. Kinetic parameters, namely the photolysis quantum yield, pseudo-first order kinetic constants and second-order kinetic constants, were satisfactorily estimated from experimental data by modeling the photochemical system. The results showed that all the congeners of the Bc-Zn mixture were photolyzed at the highest UVC doses applied, while no TOC removal was observed after 120 minutes of irradiation. The addition of H2O2 substantially accelerated Bc-Zn photodegradation, with pseudo-first order kinetic constants of one order of magnitude higher than those observed under direct photolysis. In addition, a remarkable removal of up to 71% of TOC was achieved. Statistical analyses showed that UV radiation had a much more important effect on Bc-Zn photodegradation in comparison with initial H2O2 concentration, with the best process conditions achieved for the highest specific photon emission rate (1.11×10-5 Einstein L-1 s-1). Biological assays carried out with the solutions treated by direct photolysis and UV/H2O2 revealed no residual antimicrobial activity, though photodegradation products remained non-biodegradable. In addition, toxicity analyses indicated that the zinc metal present in the antibiotic is responsible for the toxic effect on the test microorganism Vibrio fischeri. Finally, further studies should be performed to identify the by-products formed and to investigate Bc-Zn degradation in real industrial wastewater.

A indústria têxtil gera grandes volumes de efluentes com elevada carga orgânica, forte coloração e toxicidade. Neste trabalho, estuda-se o tratamento de solução aquosa contendo o corante Solophenyl Yellow Arle 154% por meio dos processos O3-H2O2/UV e foto-Fenton, avaliando-se as repostas: remoção de cor em 5 minutos, remoção de cor em 60 minutos, taxa máxima de remoção de cor e remoção de COT em 60 minutos. Os experimentos foram realizados em semibatelada com circulação usando um reator fotoquímico com campo de radiação anular coaxial, constituído de corpo cilíndrico em aço com refletor interno de alumínio para 12 lâmpadas fixadas simetricamente na superfície refletora e um tubo reator em quartzo de 0,7 L, posicionados verticalmente no eixo do refletor. Para o processo O3-H2O2/UV foram utilizadas lâmpadas Phillips TUV (36 W, 254 nm). A corrente gasosa contendo O3 foi introduzida no reator por meio de um difusor. Para o processo foto-Fenton foram utilizadas lâmpadas Sylvania (12 W cada, 300 400 nm) e concentração de Fe(II) de 0,25 mmol/L. Em ambos os processos, solução de peróxido de hidrogênio foi adicionada durante os 30 minutos iniciais de tratamento. As amostras foram analisadas por medidas de carbono orgânico total (COT) e remoção de cor (absorbância medida em 405 nm em espectrofotômetro UV-visível). Em ambos os processos utilizou-se o planejamento experimental Doehlert, definindo os valores mínimo e máximo para cada variável adotada. No caso do processo O3- H2O2/UV (ETAPA I), foram estudados os efeitos da potência elétrica total das lâmpadas (144 432 W), concentração de H2O2 (5 30 mmol/L), concentração inicial de corante (20 100 mg/L), concentração de ozônio (10 40 mg/L) e pH (3 10). No processo foto-Fenton (ETAPA II), estudaram-se os efeitos da potência (160 480 W), concentração de H2O2 (5 30 mmol/L) e concentração inicial de corante (20 100 mg/L). Os resultados da ETAPA I indicaram que o aumento da concentração do corante, em meio ácido, aumenta a remoção de cor em 5 e 60 minutos, sugerindo a eficiência da ação via ozônio molecular sob o grupo cromóforo do corante. Os melhores resultados apresentaram remoção acima de 95% em 5 e 60 minutos de tratamento. Entretanto, para a remoção de COT em 60 minutos o processo não foi eficiente, apresentando resultado máximo de 35,6%. Na ETAPA II obtiveram-se resultados menos satisfatórios para remoção de cor se comparados aos da ETAPA I (56,1% em 5 minutos e 78% em 60 minutos de tratamento), mas melhores em relação à remoção de COT em 60 minutos atigindo 45,1% de remoção. As maiores taxas de remoção de cor foram observadas nos 5 primeiros minutos de tratamento para todos os experimentos. Experimentos complementares realizados em uma terceira etapa (ETAPA III) mostraram que a aplicação do processo O3 seguido do processo foto-Fenton permitiu resultados satisfatórios tanto para remoção de cor (97,2%), quanto para remoção de COT (69,5%). O estudo da ação do processo O3 em modo contínuo e a avaliação econômica preliminar do processo integrado O3 - foto-Fenton sugerem o potencial de aplicação do tratamento integrado a indústrias têxteis. / The textile industry generates large volumes of wastewater with high organic load, strong coloration and toxicity. In this work, the treatment of an aqueous solution containing the dye Solophenyl Yellow Arle 154% was studied by the O3-H2O2/UV and photo-Fenton processes, in order to evaluate the responses color removal after 5 minutes; color removal after 60 minutes; maximum rate of color removal; and TOC removal after 60 minutes. The experiments were carried out in the semi-batch mode with circulation using a photochemical reactor with annular coaxial radiation field, consisting of a cylindrical stainless steel support with an aluminum internal reflector with 12 lamps fixed symmetrically in the internal reflecting surface, and a quartz tube reactor of 0.7 L, positioned vertically along the axis of the reflector. For the O3- H2O2/UV process, Phillips TUV lamps (36 W, 254 nm) were used; the gas stream containing zone was introduced into the reactor through a diffuser. For the photo- Fenton process, Sylvania lamps (12 W each, 300 - 400 nm) and a concentration of Fe (II) of 0.25 mmol/L were used. In both cases, the hydrogen peroxide solution was added in the first 30 minutes of treatment. The samples were analyzed by the measurement of total organic carbon (TOC) and color removal (absorbance measured at 405 nm in a UV-visible spectrophotometer). In both cases the Doehlert experimental design was used, defining the minimum and maximum values of each variable adopted. In the case of O3-H2O2/UV process (PHASE I), the effects of the total electric power of the lamps (144 - 432 W), H2O2 concentration (5 - 30 mmol/L), initial dye concentration (20 - 100 mg/L), ozone concentration (10 - 40 mg/L), and pH (3 - 10) were studied. For the photo-Fenton process, the studied variables were: total electric power of the lamps (160 - 480 W), H2O2 concentration (5 - 30 mmol/L), and initial dye concentration (20 - 100 mg/L). The results of PHASE I indicated that the increase of dye concentration in acidic conditions increases color removal after 5 and 60 minutes, thus suggesting the efficiency of molecular ozone action upon the chromophore group of the dye. The best results showed color removal above 95% after 5 and 60 minutes of treatment. However, for the TOC removal the process was not efficient, with maximum removal after 60 minutes of only 35.6%. In PHASE II less satisfactory results for color removal were obtained in comparison with PHASE I (56.1% after 5 minutes and 78% after 60 minutes of treatment), but with higher TOC removal after 60 minutes, achieving over 45.1%. The highest color removal rates were observed within the first 5 minutes of treatment for all runs. Additional experiments carried out in PHASE III showed that the oxidation by O3 followed by the photo-Fenton process enabled to achieve suitable results for both color (97.2%) and TOC removals (69.5%). The study of the O3 process in the continuous mode and a preliminary economic evaluation suggests a high potential for the use of the integrated O3-photo-Fenton process in textile industries.

A indústria têxtil gera grandes volumes de efluentes com elevada carga orgânica, forte coloração e toxicidade. Neste trabalho, estuda-se o tratamento de solução aquosa contendo o corante Solophenyl Yellow Arle 154% por meio dos processos O3-H2O2/UV e foto-Fenton, avaliando-se as repostas: remoção de cor em 5 minutos, remoção de cor em 60 minutos, taxa máxima de remoção de cor e remoção de COT em 60 minutos. Os experimentos foram realizados em semibatelada com circulação usando um reator fotoquímico com campo de radiação anular coaxial, constituído de corpo cilíndrico em aço com refletor interno de alumínio para 12 lâmpadas fixadas simetricamente na superfície refletora e um tubo reator em quartzo de 0,7 L, posicionados verticalmente no eixo do refletor. Para o processo O3-H2O2/UV foram utilizadas lâmpadas Phillips TUV (36 W, 254 nm). A corrente gasosa contendo O3 foi introduzida no reator por meio de um difusor. Para o processo foto-Fenton foram utilizadas lâmpadas Sylvania (12 W cada, 300 400 nm) e concentração de Fe(II) de 0,25 mmol/L. Em ambos os processos, solução de peróxido de hidrogênio foi adicionada durante os 30 minutos iniciais de tratamento. As amostras foram analisadas por medidas de carbono orgânico total (COT) e remoção de cor (absorbância medida em 405 nm em espectrofotômetro UV-visível). Em ambos os processos utilizou-se o planejamento experimental Doehlert, definindo os valores mínimo e máximo para cada variável adotada. No caso do processo O3- H2O2/UV (ETAPA I), foram estudados os efeitos da potência elétrica total das lâmpadas (144 432 W), concentração de H2O2 (5 30 mmol/L), concentração inicial de corante (20 100 mg/L), concentração de ozônio (10 40 mg/L) e pH (3 10). No processo foto-Fenton (ETAPA II), estudaram-se os efeitos da potência (160 480 W), concentração de H2O2 (5 30 mmol/L) e concentração inicial de corante (20 100 mg/L). Os resultados da ETAPA I indicaram que o aumento da concentração do corante, em meio ácido, aumenta a remoção de cor em 5 e 60 minutos, sugerindo a eficiência da ação via ozônio molecular sob o grupo cromóforo do corante. Os melhores resultados apresentaram remoção acima de 95% em 5 e 60 minutos de tratamento. Entretanto, para a remoção de COT em 60 minutos o processo não foi eficiente, apresentando resultado máximo de 35,6%. Na ETAPA II obtiveram-se resultados menos satisfatórios para remoção de cor se comparados aos da ETAPA I (56,1% em 5 minutos e 78% em 60 minutos de tratamento), mas melhores em relação à remoção de COT em 60 minutos atigindo 45,1% de remoção. As maiores taxas de remoção de cor foram observadas nos 5 primeiros minutos de tratamento para todos os experimentos. Experimentos complementares realizados em uma terceira etapa (ETAPA III) mostraram que a aplicação do processo O3 seguido do processo foto-Fenton permitiu resultados satisfatórios tanto para remoção de cor (97,2%), quanto para remoção de COT (69,5%). O estudo da ação do processo O3 em modo contínuo e a avaliação econômica preliminar do processo integrado O3 - foto-Fenton sugerem o potencial de aplicação do tratamento integrado a indústrias têxteis. / The textile industry generates large volumes of wastewater with high organic load, strong coloration and toxicity. In this work, the treatment of an aqueous solution containing the dye Solophenyl Yellow Arle 154% was studied by the O3-H2O2/UV and photo-Fenton processes, in order to evaluate the responses color removal after 5 minutes; color removal after 60 minutes; maximum rate of color removal; and TOC removal after 60 minutes. The experiments were carried out in the semi-batch mode with circulation using a photochemical reactor with annular coaxial radiation field, consisting of a cylindrical stainless steel support with an aluminum internal reflector with 12 lamps fixed symmetrically in the internal reflecting surface, and a quartz tube reactor of 0.7 L, positioned vertically along the axis of the reflector. For the O3- H2O2/UV process, Phillips TUV lamps (36 W, 254 nm) were used; the gas stream containing zone was introduced into the reactor through a diffuser. For the photo- Fenton process, Sylvania lamps (12 W each, 300 - 400 nm) and a concentration of Fe (II) of 0.25 mmol/L were used. In both cases, the hydrogen peroxide solution was added in the first 30 minutes of treatment. The samples were analyzed by the measurement of total organic carbon (TOC) and color removal (absorbance measured at 405 nm in a UV-visible spectrophotometer). In both cases the Doehlert experimental design was used, defining the minimum and maximum values of each variable adopted. In the case of O3-H2O2/UV process (PHASE I), the effects of the total electric power of the lamps (144 - 432 W), H2O2 concentration (5 - 30 mmol/L), initial dye concentration (20 - 100 mg/L), ozone concentration (10 - 40 mg/L), and pH (3 - 10) were studied. For the photo-Fenton process, the studied variables were: total electric power of the lamps (160 - 480 W), H2O2 concentration (5 - 30 mmol/L), and initial dye concentration (20 - 100 mg/L). The results of PHASE I indicated that the increase of dye concentration in acidic conditions increases color removal after 5 and 60 minutes, thus suggesting the efficiency of molecular ozone action upon the chromophore group of the dye. The best results showed color removal above 95% after 5 and 60 minutes of treatment. However, for the TOC removal the process was not efficient, with maximum removal after 60 minutes of only 35.6%. In PHASE II less satisfactory results for color removal were obtained in comparison with PHASE I (56.1% after 5 minutes and 78% after 60 minutes of treatment), but with higher TOC removal after 60 minutes, achieving over 45.1%. The highest color removal rates were observed within the first 5 minutes of treatment for all runs. Additional experiments carried out in PHASE III showed that the oxidation by O3 followed by the photo-Fenton process enabled to achieve suitable results for both color (97.2%) and TOC removals (69.5%). The study of the O3 process in the continuous mode and a preliminary economic evaluation suggests a high potential for the use of the integrated O3-photo-Fenton process in textile industries.

<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; H₂O₂,&nbsp; kombinovani&nbsp; O ₃/UV&nbsp; proces&nbsp; i kombinovani&nbsp; H ₂O₂<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^-1 ;&nbsp; 4,68&plusmn;0,41&nbsp; lm^-1 mg ^-1)&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>^-1<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>^-1<span id="cke_bm_193E" style="display: none;">&nbsp;</span> mg^-1 ), 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>^-1<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>^-1<span id="cke_bm_204E" style="display: none;">&nbsp;</span> mg ^-1<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 O₃/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 ₃/mg DOC. U vodi iz Temerina najveće smanjenje PFTHM (za&nbsp; 27%) je pri dozi od 3,0 mg O ₃ /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; O₃ /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; O₃ /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_3/mg DOC i UV zračenja od 6000 mJ/cm ^{2 .} U vodi iz Kikinde se PFTHM smanjuje za 50% pri dozi od 3,0 mg O ₃/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; O₃ /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; O₃ /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 ₂O₂<br />i&nbsp; UV zračenja u sintetičkom matriksu (za do 17% DOC, 70% UV 254 ), u vodi iz Kikinde (za do 22% DOC, 53% UV₂₅₄), i vodi iz Temerina (za do 7% DOC, 68% UV<br />₂₅₄), u odnosu na vrednosti u sirovoj vodi, se postižu pri dozi H ₂O₂ i UV zračenja od 3,0 mg H₂O₂/mg DOC i 6000 mJ/cm ² .<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 H₂O₂/mg DOC i 6000 mJ/cm ² ,&nbsp; dok se smanjenje PFHAA (za 35%)&nbsp; postiže primenom doze vodonik-peroksida i UV zračenja od 1,0 mg H ₂O₂ /mg&nbsp; DOC i 3000 mJ/cm ² . U vodi izKikinde&nbsp; H₂O₂ /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_{<span id="cke_bm_235S" style="display: none;">&nbsp;</span>2<span id="cke_bm_235E" style="display: none;">&nbsp;</span>}O₂/mg&nbsp; DOC&nbsp; i&nbsp; 600&nbsp; mJ/cm ² .H<span id="cke_bm_184S" style="display: none;">&nbsp;</span>₂<span id="cke_bm_184E" style="display: none;">&nbsp;</span>O₂<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 H₂O₂/mg DOC i 600 mJ/c<span id="cke_bm_236E" style="display: none;">&nbsp;</span>m ² ,&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 H₂O₂ /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; O₃<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>

Tesis por compendio / [ES] Los procesos (foto-)Fenton fueron empleados para degradar fluoroquinolonas (FQ) (una clase de antibióticos sintéticos considerados CEC) como contaminantes modelo en diferentes condiciones: pH (3 - 8), concentración de contaminante (3 - 300 μM), número de FQ presentes (1, 3 y 5), y matrices de agua (agua ultrapura, salina y de WWTP simulada). Los experimentos se realizaron a escala banco y planta piloto, empleando luz solar (simulada y real) e irradiaciones con luz ultravioleta. Las velocidades de degradación de los contaminantes obtenidas con procesos tipo-Fenton se compararon con las análogas de fotólisis, fotocatálisis heterogénea y H2O2/UV. En igualdad de condiciones, solo a través del proceso foto-Fenton se logró una mineralización significativa de las FQs. En aquellos casos en los que el carbono orgánico total no mostró una disminución considerable, la razón se atribuye a la liberación de subproductos de oxidación. EEM-PARAFAC ha demostrado ser una técnica económica, veloz y que no requiere del uso de reactivos, para seguir simultáneamente la eliminación de la degradación de hasta 5 FQs fluorescentes presentes en una misma muestra, en presencia de interferencias sin calibrar, y obtener información sobre las posibles estructuras moleculares de los intermediarios de reacción. Los resultados indicaron que la fotólisis por sí sola no es capaz de producir cambios importantes en la estructura de las FQs, mientras que con (foto-)Fenton sí que se observó una notable disminución de los scores de los componentes PARAFAC asociados con los compuestos del tipo FQ. Los ensayos de zona de inhibición empleando E. coli mostraron que la actividad antibiótica disminuyó en paralelo con la desintegración de todos los componentes PARAFAC relacionados con las FQs y subproductos similares a estas. El otro aspecto importante de la tesis fue el uso de procesos Fenton basados en ZVI. Algunos CEC, como los compuestos nitroaromáticos, exhiben tasas de degradación lentas incluso cuando son degradadas por una AOP. El desarrollo de trenes de tratamiento ZVI para la degradación de contaminantes ha despertado un gran interés en los últimos años. Este enfoque consiste en un primer pretratamiento solo con ZVI (es decir, reducción, deshalogenación), seguido del proceso Fenton aprovechando los iones de hierro liberados en el primer paso. Con el fin de analizar las posibles ventajas e inconvenientes de esta estrategia en las aplicaciones de tratamiento de aguas residuales, se ha estudiado este enfoque empleando micropartículas de ZVI (mZVI) comerciales utilizando ácido p-nitrobenzoico (PNBA) como contaminante modelo. Se analizó el efecto de la cantidad inicial de mZVI, H2O2, pH, conductividad, aniones y oxígeno disuelto. Utilizando agua natural en condiciones aeróbicas, pH inicial 3,0, y adicionando 1,4 g/L de mZVI, se consiguió en 2 h una reducción del 83% de PNBA 6 μM en ácido p-aminobenzoico (PABA). Se investigó también la conveniencia de separar las mZVI después de la fase reductora (antes de la etapa Fenton) así como la reutilización de las mZVI. El paso de Fenton contra el PABA, más reactivo que PNBA, requirió 50 mg/L de H2O2 para lograr una eliminación de más del 96% en 15 min a pH 7,5 (pH final del pretratamiento reductivo). Las mZVI reutilizadas fueron efectivas por lo menos por un ciclo completo (reducción/oxidación). Este enfoque puede ser interesante para tratar aguas residuales que contienen contaminantes inicialmente resistentes al radical hidroxilo (HO), pero fácilmente reducibles, pudiendo disminuir su carga tóxica y aumentar su reactividad para un paso de oxidación posterior. / [CA] Fenton i foto-Fenton van ser emprats per a degradar fluoroquinolones (FQ) (una classe d'antibiòtics sintètics considerats CEC) com a contaminants model en diferents condicions: pH (3 - 8), concentració de contaminant (3 - 300 μM), nombre de FQ presents (1, 3 i 5), i matriu d'aigua (aigua ultrapura, salada i de WWTP simulada). Els experiments es van realitzar a escala de laboratori i planta pilot, emprant llum solar (simulada i real) i irradiacions amb llum ultraviolada. Les velocitats de degradació de contaminants obtingudes amb processos tipus-Fenton es van comparar amb fotòlisi, fotocatàlisi heterogènia i H2O2/UV. En igualtat de condicions, només a través del procés foto-Fenton es va aconseguir una mineralització significativa de FQ. En aquells casos en els quals el carboni orgànic total no va mostrar una disminució considerable, la raó s'atribueix a l'alliberament de subproductes d'oxidació. EEM-PARAFAC ha demostrat ser una tècnica econòmica, que no requereix de l'ús de reactius, i ràpida, per a seguir simultàniament l'eliminació de la degradació de fins a 5 FQ fluorescents presents en una mateixa mostra, en presència d'interferències sense calibrar, i obtindre informació sobre les possibles estructures moleculars dels intermediaris de reacció. Els resultats van indicar que la fotòlisi per si sola no és capaç de produir canvis importants en l'estructura de les FQ, mentre que amb (foto-)Fenton, sí que es va observar una notable disminució dels scores dels components PARAFAC associats amb el nucli de FQ. Els assajos de zona d'inhibició que empren E. coli van mostrar que l'activitat antibiòtica va disminuir en paral·lel amb la desintegració de tots els components PARAFAC relacionats amb FQ i subproductes similars a FQ. L'altre aspecte important de la tesi va ser l'ús de processos Fenton basats en ZVI. Alguns CEC, com els compostos nitroaromàtics, exhibeixen taxes de degradació lentes fins i tot quan són degradats per un AOP. El desenvolupament de trens de tractament basats en ZVI per a la degradació de contaminants ha despertat un gran interés en els últims anys. Aquesta aproximaciót consisteix en un primer pretractament amb ZVI (és a dir, reducció, deshalogenación), seguit del procés Fenton aprofitant els ions de ferro alliberats en el primer pas. Amb la finalitat d'analitzar els possibles avantatges i inconvenients d'aquesta estratègia en les aplicacions de tractament d'aigües residuals, s'han emprat micropartícules de ZVI (mZVI) comercials. Utilitzant àcid p-nitrobenzoic (PNBA) com a contaminant model, es va analitzar l'efecte de la quantitat inicial de mZVI, H2O2, pH, conductivitat, anions i oxigen dissolt. Utilitzant aigua natural en condicions aeròbiques, pH inicial 3,0, i addicionant 1,4 g/L de mZVI, es va aconseguir en 2 h una reducció del 83% de PNBA 6 μM a àcid p-aminobenzoic (PABA). Es va investigar també la conveniència d'eliminar les mZVI després de la fase reductora (abans de l'etapa Fenton) així com la reutilització de les mZVI. El pas de Fenton front el PABA, més reactiu que PNBA, va requerir 50 mg/L de H2O2 per a aconseguir una eliminació de més del 96% en 15 min a pH 7,5 (pH final del pretractament reductiu). Les mZVI reutilitzades van ser efectives almenys amb un cicle complet (reducció/oxidació). Aquest enfocament pot ser interessant per a tractar aigües residuals que contenen contaminants inicialment resistents al HO, però que es redueixen fàcilment, podent disminuir la seua càrrega tòxica i augmentar la seua reactivitat per a un pas d'oxidació posterior. / [EN] Dark Fenton and photo-Fenton were employed to degrade Fluoroquinolones (FQs) (a class of synthetic antibiotics considered CEC) as model pollutants under different conditions: pH (3 - 8), pollutant concentration (3 - 300 μM), number of present FQs (1, 3 and 5), and water matrix (ultra-pure, salty and simulated wastewater). Experiments were performed at bench and pilot plant scales, employing sunlight (simulated and real) and ultraviolet light irradiations. Obtained pollutant abatement rates with Fenton-related processes were compared with photolysis, heterogeneous photocatalysis and H2O2/UV. At equal conditions, only through photo-Fenton process significant FQs mineralization were achieved. In those cases where total organic carbon had not exhibit a considerable decrease, the reason was attributed to the release of oxidation by-products. Since FQs are fluorescent, we decided to employ fluorescence excitation-emission matrices (EEM) in combination with the chemometric tool, Parallel Factor Analysis (PARAFAC), to track their degradations. Although EEM-PARAFAC related studies are usually focused towards the characterization and monitoring of dissolved organic matter (DOM) in natural waters and wastewater effluents (work also included in this PhD Thesis following the DOM along the different stages of a drinking water plant), it is barely the first time that it is used for the purposes we have here proposed. The objective is demonstrating that EEM-PARAFAC could be a feasible complementary methodology for the study of fluorescent CECs degradations, avoiding the use of expensive and sophisticated techniques (e.g mass spectrometry), not always available. The other important aspect of the PhD Thesis was the use of ZVI-based Fenton processes. Some CECs such as nitroaromatic compounds, exhibit slow degradation rates even with AOPs. The development of new and more efficient ZVI treatment trains for pollutant degradation has been attracting great interest in the last few years. This approach consists of a first pre-treatment only with ZVI (i.e. reduction, dehalogenation), followed by a Fenton oxidation taking advantage of the released iron ions from the first step. In order to analyse the strategy's plausible advantages and potential drawbacks within wastewater treatment applications, reductive/oxidative treatment train based on commercial ZVI microparticles (mZVI) has been studied. The effect of the initial amount of mZVI, H2O2, pH, conductivity, anions, dissolved oxygen were analysed using p-nitrobenzoic acid (PNBA) as model pollutant. 83% reduction of PNBA 6 μM into p-aminobenzoic acid (PABA) was achieved in natural water at initial pH 3.0 and 1.4 g/L of mZVI under aerobic conditions in 2 h. An evaluation of the convenience of removing mZVI after the reductive phase (before the Fenton oxidation one) was investigated together with mZVI reusability. The Fenton step against the more reactive PABA required 50 mg/L of H2O2 to achieve more than 96% removal in 15 min at pH 7.5 (final pH from the pre-reductive step). At least one complete reuse cycle (reduction/oxidation) was obtained with the separated mZVI. This approach might be interesting to treat wastewater containing pollutants initially resistant to hydroxyl radical (HO), but easily reduced, being able to decrease its toxic load as well as increasing its reactivity for a subsequent oxidation step. / Sciscenko, IM. (2021). Emerging Photochemical Processes Involving Iron for Wastewater Treatment [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/177357 / Compendio

[ES] El mundo se enfrenta a una profunda crisis asociada al agua y la reutilización de aguas residuales urbanas (UWW), especialmente en agricultura, se presenta como una posible solución para abordar este problema. No obstante, la reutilización se debe promover dentro de unos límites mínimos de calidad del agua, los cuales pueden alcanzarse mediante la implementación de eficientes tratamientos terciaros en las actuales plantas de tratamiento de aguas residuales urbanas. En las últimas décadas, los Procesos de Oxidación Avanzada (POA), basados en la generación de especies reactivas del oxígeno altamente oxidantes y no selectivas, se han planteado como alternativa a los tratamientos convencionales para desinfección y descontaminación de agua residual. El objetivo general de este estudio es, por tanto, la evaluación de nuevos POA para desinfección y descontaminación simultánea de agua, investigando: (i) fotocatálisis heterogénea solar con ZnO modificado (Ce, Yb y Fe) y TiO2-P25 de referencia, (ii) peroximonosulfato (PMS) bajo radiación solar natural (PMS/Solar), (iii) POA basados en radical sulfato utilizando PMS y radiación UV-C (PMS/UV-C) y (iv) combinación de ZnO modificado con PMS como estrategia de tratamiento. Los objetivos biológicos y químicos analizados en este estudio fueron: tres patógenos de impacto en salud humana (dos bacterias gram-negativas Escherichia coli, Pseudomonas spp y una gram-positiva Enterococcus spp) y tres Contaminantes de Preocupación Emergente (CE) (Diclofenaco-DCF, Sulfametoxazol-SMX y Trimetoprim-TMP). La fotoactividad de ZnO modificado con Ce, Yb o Fe se evaluó a escala de laboratorio (200 mL), obteniendo buenas cinéticas de inactivación bacteriana y degradación de CE. El ZnO-Ce mostró el mejor rendimiento, no obstante, se descartó el escalado de este proceso tanto su aplicación directa, considerando su similar eficiencia en comparación con TiO2-P25 y por el alto coste del tratamiento, como en combinación con PMS, por la la liberación de Zn2+ al agua tratada. El uso directo de PMS como agente oxidante para el tratamiento de agua y UWW se ha demostrado en este estudio, aumentado su eficiencia al ser el sistema irradiado tanto con lámparas UV-C como con luz solar natural. Se han postulado diferentes mecanismos de inactivación y degradación de CE para cada tipo de irradiación: activación de PMS para generar radicales (con fotones UV-C) y la no activación o mecanismo de oxidación directo (con luz solar natural). La capacidad de los procesos PMS/Solar y PMS/UV-C se evaluó en UWW a escala de planta piloto en un Colector Parabólico Compuesto (10 L) y en una planta piloto de UV-C (80 L), respectivamente. El mejor rendimiento de tratamiento se alcanzó con una concentración de PMS de 1 mM en ambos casos, logrando una inactivación exitosa de todos los objetivos microbianos (incluyendo bacterias resistentes a antibióticos), sin observar recrecimiento bacteriano tras 48 h y eliminando de manera eficiente los CE. Por otro lado, la eliminación eficiente de genes de resistentes a antibióticos y productos de transformación se obtuvo con PMS/UV-C, mientras que éstos parámetros siguen siendo un reto a abordar en el caso del proceso PMS/Solar. En ningún caso se observó toxicidad del agua tratada para Aliivibrio fischeri, excluyendo un efecto nocivo para el medio ambiente receptor del efluente, y solo un leve efecto fitotóxico en el crecimiento de dos de las tres semillas analizadas (L. sativum y S. alba), indicando la idoneidad del efluente para su reutilización en riego. Finalmente, el análisis de costes demostró que este factor clave podría ser una barrera importante para la implementación del proceso PMS/Solar en plantas centralizadas de tratamiento de UWW. No obstante, su consideración como sistemas descentralizados asociados a pequeños volúmenes de agua en zonas con alta incidencia de radiación solar, ahorrando costes energéticos mediante el aprovechamiento de la luz solar, podría ser una opción real y asequible. / [CA] El món s'enfronta a una profunda crisi associada a l'aigua i la reutilització d'aigües residuals urbanes (UWW), especialment en agricultura, es presenta com una possible solució per a abordar aquest problema. No obstant això, la reutilització s'ha de promoure dins d'uns límits mínims de qualitat de l'aigua, els quals poden aconseguir-se mitjançant la implementació d'eficients tractaments terciaris en les actuals plantes de tractament d'aigües residuals urbanes. En les últimes dècades, els Processos Avançats d'Oxidació (PAO), basats en la generació d'espècies reactives d'oxigen altament oxidants i no selectives, s'han plantejat com a alternativa als tractaments convencionals per a desinfecció i descontaminació d'aigua residual. L'objectiu general d'aquest estudi és, per tant, l'avaluació de nous POA per a desinfecció i descontaminació simultània d'aigua, investigant: (i) fotocatàlisi heterogènia solar amb ZnO modificat (Ce, Yb i Fe) i TiO2-P25 de referència, (ii) peroximonosulfat (PMS) baix radiació solar natural (PMS/Solar), (iii) POA basats en radical sulfat utilitzant PMS i radiació UV-C (PMS/UV-C) i (iv) combinació de ZnO modificat amb PMS com a estratègia de tractament. Els objectius biològics i químics analitzats en aquest estudi van ser: tres patògens d'impacte en salut humana (dos bacteris gram-negatius Escherichia coli, Pseudomonas spp i un gram-positiu Enterococcus spp) i tres Contaminants de Preocupació Emergent (CE) (Diclofenac-DCF, Sulfametoxazol-SMX i Trimetoprim-TMP). La fotoactivitat de ZnO modificat amb Ce, Yb o Fe es va avaluar a escala de laboratori (200 mL), obtenint bones cinètiques d'inactivació bacteriana i degradació de CE. El ZnO-Ce va mostrar el millor rendiment, no obstant això, es va descartar l'escalat d'aquest procés tant mitançant la seua aplicació directa o com en combinació amb PMS, considerant la seua similar eficiència en comparació amb TiO2-P25, l'alt cost del tractament i l'alliberament de Zn2+ a l'aigua tractada. L'ús directe de PMS com a agent oxidant per al tractament d'aigua i UWW s'ha demostrat en aquest estudi, augmentat la seua eficiència quan el sistema és irradiat tant amb llums UV-C com amb llum solar natural. S'han postulat diferents mecanismes d'inactivació i degradació de CE per a cada tipus d'irradiació: activació de PMS per a generar radicals (amb fotons UV-C) i la no activació o mecanisme d'oxidació directe (amb llum solar natural). La capacitat dels processos PMS/Solar i PMS/UV-C es va avaluar en UWW a escala de planta pilot en un Col·lector Parabòlic Compost (10 L) i en una planta pilot d'UV-C (80 L), respectivament. El millor rendiment de tractament es va aconseguir amb una concentració de PMS d'1 mm en tots dos casos, aconseguint una inactivació reeixida de tots els objectius microbians (incloent bacteris resistents a antibiòtics), sense observar recreixement bacterià després de 48 h i eliminant de manera eficient els CE. D'altra banda, l'eliminació eficient de gens de resistents a antibiòtics i productes de transformació es va obtindre amb PMS/UV-C, mentre que aquests paràmetres continuen sent un repte a abordar en el cas del procés PMS/Solar. En cap cas es va observar toxicitat a l'aigua tractada per a Aliivibrio fischeri, excloent un efecte nociu per al medi ambient receptor de l'efluent, i només un lleu efecte fitotòxic en el creixement de dos de les tres llavors analitzades (L. sativum i S. alba), indicant la idoneïtat de l'efluent per a la seua reutilització en reg. Finalment, l'anàlisi de costos va demostrar que aquest factor clau podria ser una barrera important per a la implementació del procés PMS/Solar en plantes centralitzades de tractament de UWW. No obstant això, la seua consideració com a sistemes descentralitzats associats a xicotets volums d'aigua en zones amb alta incidència de radiació solar, estalviant costos energètics mitjançant l'aprofitament de la llum solar, podria ser una opció real i assequible. / [EN] It is well recognized that the world is facing a water crisis and the reuse of urban wastewater (UWW) in agriculture, has been gaining attention as a reliable solution to address this problem. It is mandatory to promote the safe water reuse and minimum water quality limits could be achieved by upgrading the Urban Wastewater Treatment Plants, through the addition of an efficient tertiary treatment. In the last decades, Advanced Oxidation Processes (AOPs), relying on the potential generation of highly oxidant, reactive and non-selective Reactive Oxygen Species (ROS), have been raised as alternative to conventional treatments for both water disinfection and decontamination. The general aim of this study is the assessment of novel AOPs for the simultaneous disinfection and decontamination of water, investigating (i) solar heterogeneous photocatalysis, involving modified ZnO with Ce, Yb and Fe and the benchmark TiO2-P25, (ii) peroxymonosulfate (PMS) under natural solar radiation (PMS/Solar), (iii) Sulfate radical-based AOPs (SR-AOPs) involving PMS and UV-C radiation (PMS/UV-C) and (iv) combination of the best-performing photocatalytic material with PMS (PMS/modified ZnO). The involved biological and chemical targets in this study were: three human health impact pathogens (two gram-negative bacteria Escherichia coli, Pseudomonas spp. and the gram-positive Enterococcus spp.) and three Contaminants of Emerging Concern (CECs, Diclofenac-DCF, Sulfamethoxazole-SMX and Trimethoprim-TMP). Photoactivity of modified ZnO with Ce, Yb or Fe was assessed in 200-mL vessel reactors, attaining good target's removal kinetic rates. Best performing material was ZnO-Ce, but its feasibility for a further up-scaling was discarded both as photocatalyst alone, considering the similar performances obtained, compared to TiO2-P25 and the high treatment cost, and in combination with PMS, due to the release of high amount of Zn2+. PMS alone has been proven to be an effective oxidant agent for water and UWW treatment, increasing its effectiveness when illuminated with photons from UV-C lamps and natural sunlight. Nevertheless, different inactivation and CECs degradation mechanisms have been postulated for each type of irradiation, and according to the activation of PMS (with UV-C photons) or non-activation (under natural sunlight). The capability of PMS/Solar and PMS/UV-C processes were evaluated in actual UWW at pilot plant scale in 10-L Compound Parabolic Collector and in 80L UV-C pilot plant, respectively. Optimal load of PMS was found to be 1 mM in both cases, achieving successful inactivation of natural occurring bacteria and their antibiotic resistant counterparts, without observing bacterial regrowth after 48h and efficiently eliminating CECs. Efficient removal of antibiotic resistant genes (ARGs) and transformation products (TPs) was obtained by PMS/UV-C, while their elimination is still a challenge to be addressed in PMS/Solar process. Reclaimed UWW obtained by both PMS/Solar and PMS/UV-C process showed no toxicity towards Aliivibrio fischeri, excluding a harmful effect towards the receiving aquatic environment after effluent discharge, and a very slightly phytotoxic effect for growth of two out of the three tested seeds (L. sativum and S. alba), indicating the suitability of this water for its subsequent reuse for agriculture. The analysis of the treatment cost revealed that this key factor could be an important barrier for implementation of PMS/Solar process in large centralized UWW treatment plants. Nevertheless, its consideration as decentralized systems associated to small volume of water in areas with a high solar radiation incidence, saving energy costs by using natural solar radiation, could be a real and affordable option. / Berruti, I. (2022). Assessment of novel Advanced Oxidation Processes for the Simultaneous Disinfection and Decontamination of Water [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/183052

[ES] Las tecnologías convencionales para el tratamiento de aguas contaminadas no logran abordar la eliminación de contaminantes de preocupación emergente (CECs), lo que subraya la necesidad de implementar nuevas estrategias aplicables a escala industrial. Los Procesos de Oxidación Avanzada (AOPs) surgen como una opción prometedora para la eliminación de contaminantes orgánicos, gracias a su capacidad para generar especies altamente reactivas como los radicales hidroxilo en concentraciones suficientes para purificar el agua. En este contexto, el objetivo principal de esta Tesis Doctoral es diseñar y sintetizar fotocatalizadores destinados a la remediación de aguas residuales con contaminantes orgánicos. En una primera etapa, se abordó la derivatización covalente de un conocido colorante, la Riboflavina (RF), sobre partículas de sílice (SiO2@RF) con el fin de generar una superficie altamente cargada de este colorante orgánico y así modificar sus propiedades fotofísicas. Tras estudiar los procesos fotocatalíticos de eliminación de contaminantes y realizar una exhaustiva caracterización fotofísica, se postuló un nuevo mecanismo fotocatalítico para este nuevo fotocatalizador heterogéneo. Así, debido a la gran proximidad entre las moléculas de Riboflavina en la superficie del fotocatalizador SiO2@RF se evitó que el colorante experimentara cruce intersistemas, excluyendo así la formación del estado excitado triplete y, por lo tanto, del oxígeno singlete. Consecuentemente, se mejoró la fotoestabilidad de la riboflavina heterogenizada en el fotocatalizador SiO2@RF respecto a su comportamiento en medio homogéneo. A su vez, el proceso de fotocatálisis heterogénea de degradación de contaminantes ocurrió mediante reacciones de transferencia electrónica desde el estado excitado singlete. A continuación, se exploró la influencia del grosor de la capa de TiO2 en la eficiencia fotocatalítica de fotocatalizadores soportados de SiO2@TiO2. El objetivo principal fue optimizar la eficiencia del TiO2 en los procesos fotocatalíticos de degradación de contaminantes. Se introdujeron modificaciones en el método sintético sol-gel para los fotocatalizadores SiO2@TiO2, controlando tanto la velocidad de formación como el grosor de la capa de TiO2 sobre las esferas de SiO2. Tras caracterizarlos, se evaluó la eficiencia fotocatalítica en relación con la cantidad de TiO2 presente en cada fotocatalizador SiO2@TiO2. Los resultados revelaron una dependencia significativa de la actividad fotocatalítica con el grosor de la capa de TiO2, que se correlacionó con la respuesta de la fotoluminiscencia de cada muestra. En este sentido, se llevó a cabo la síntesis y caracterización de un fotocatalizador de SiO2@TiO2, así como de lana de vidrio recubierta con TiO2 (GW_TiO2). Estos materiales fueron desarrollados para eliminar un CEC, el sulfametoxazol (SMX), en una matriz simulada de aguas urbanas. Se exploró la incorporación de nanocristales de Fe3O4 en la capa del fotocatalizador SiO2@TiO2 con la intención de que actúen como trampas para los electrones fotogenerados y así, minimizar su recombinación al tiempo que ayudan a la recuperación del fotocatalizador del medio de reacción. La sinergia entre el TiO2 y el Fe3O4 en el nuevo fotocatalizador SiO2@TiO2@Fe3O4 se evaluó en la eliminación de un contaminante orgánico modelo bajo radiación UV-A. Los resultados mostraron que el Fe3O4 unido al TiO2 puede desarrollar reacciones de foto-Fenton a pH neutro. Se evaluaron H2O2 y PMS como promotores de radicales, mejorando en gran medida el poder foto-oxidativo del nuevo fotocatalizador SiO2@TiO2@Fe3O4. Así, el PMS fue más eficiente que el H2O2. Finalmente, se diseñó y sintetizó un nuevo compuesto macroscópico que mejoraba las propiedades fotocatalíticas de los existentes. Este nuevo material está constituido por micropartículas de SiO2@TiO2 unidas covalentemente a lana de vidrio. El material final se implementó en un fotorreactor de flujo continuo especialmente diseñado. / [CA] Les tecnologies convencionals per al tractament d'aigües contaminades no aconsegueixen abordar l'eliminació de contaminants de preocupació emergent (CECs), el que subratlla la necessitat d'implementar noves estratègies que tinguin aplicació a escala industrial. Els Processos d'Oxidació Avançada (AOPs) emergeixen com una opció prometedora per a l'eliminació de contaminants orgànics, gràcies a la seva capacitat per generar espècies altament reactives com els radicals hidroxil en concentracions suficients per purificar l'aigua. Aquí, l'objectiu principal de la present Tesi Doctoral és el disseny i la síntesi de fotocatalitzadors destinats a la remediació d'aigües residuals amb contaminants orgànics. En una primera etapa, es va abordar la derivatització covalent d'un conegut colorant, la Riboflavina (RF), sobre partícules de sílice (SiO2@RF) amb la finalitat de generar una superfície altament carregada d'aquest colorant orgànic i així modificar les seves propietats fotofísiques. Després d'estudiar els processos fotocatalítics d'eliminació de contaminants i realitzar una exhaustiva caracterització fotofísica, es va postular un nou mecanisme fotocatalític per aquest nou fotocatalitzador heterogeni. Així, a causa de la gran proximitat entre les molècules de Riboflavina en la superfície del fotocatalitzador SiO2@RF es va evitar que el colorant experimentés creuament intersistemes, excloent així la formació de l'estat excitat triplet i, per tant de l'oxigen singlet. Conseqüentment, es va millorar la fotoestabilitat de la riboflavina heterogenitzada en el fotocatalitzador SiO2@RF respecte al seu comportament en medi homogeni. Al seu torn, el procés de fotocatàlisi heterogènia de degradació de contaminants va ocórrer mitjançant reaccions de transferència electrònica des de l'estat excitat singlet. A continuació, es va explorar la influència de l'espessor de la capa de TiO2 en l'eficiència fotocatalítica de fotocatalitzadors suportats de SiO2@TiO2. L'objectiu principal va ser optimitzar l'eficiència del TiO2 en els processos fotocatalítics de degradació de contaminants. Es van introduir modificacions en el mètode sintètic sol-gel per als fotocatalitzadors SiO2@TiO2, controlant tant la velocitat de formació com l'espessor de la capa de TiO2 sobre les esferes de SiO2. Després de caracteritzar-los, es va avaluar l'eficiència fotocatalítica en relació amb la quantitat de TiO2 present en cada fotocatalitzador SiO2@TiO2. Els resultats van revelar una dependència significativa de l'activitat fotocatalítica amb l'espessor de la capa de TiO2, que es va correlacionar amb la resposta de la fotoluminiscència de cada mostra. En aquest sentit, es va dur a terme la síntesi i caracterització d'un fotocatalitzador de SiO2@TiO2, així com de llana de vidre recoberta amb TiO2 (GW_TiO2). Aquests materials van ser desenvolupats per eliminar un CEC, el sulfametoxazol (SMX), en una matriu simulada d'aigües urbanes. Es va explorar la incorporació de nanocristalls de Fe3O4 en la capa del fotocatalitzador SiO2@TiO2 amb la intenció que actuïn com a trampes per als electrons fotogenerats i així, minimitzar la seva recombinació alhora que ajudin a la recuperació del fotocatalitzador del medi de reacció. La sinergia entre el TiO2 i el Fe3O4 en el nou fotocatalitzador SiO2@TiO2@Fe3O4 es va avaluar en l'eliminació d'un contaminant orgànic model sota radiació UV-A. Els resultats van mostrar que el Fe3O4 unit al TiO2 pot desenvolupar reaccions de foto-Fenton a pH neutre. Es van avaluar H2O2 i PMS com a promotors de radicals, millorant en gran mesura el poder foto-oxidatiu del nou fotocatalitzador SiO2@TiO2@Fe3O4. Així, el PMS va ser més eficient que el H2O2. Finalment, es va dissenyar i sintetitzar un nou composite macroscòpic que millorava les propietats fotocatalítiques dels existents. Aquest nou materialestà constituït per micropartícules de SiO2@TiO2 unides covalentment a llana de vidre. El material final es va implementar a un fotorreactor de flux continu. / [EN] Conventional technologies for treating contaminated water fail to address the removal of emerging contaminants of concern (CECs), highlighting the need for implementing new strategies applicable on an industrial scale. Among the various techniques used in contaminated water treatment, Advanced Oxidation Processes (AOPs) emerge as a promising option for organic contaminant removal, thanks to their ability to generate highly reactive species like hydroxyl radicals in sufficient concentrations to purify water. In this context, the main objective of this doctoral thesis is to design and synthesize photocatalysts for the remediation of wastewater with high concentrations of organic pollutants. First, the covalent derivatization of Riboflavin (RF) onto silica particles (SiO2@RF) was addressed to generate a highly charged surface of this organic dye and modify its photophysical properties. After studying the photocatalytic processes for contaminant removal and conducting the photophysical characterization, a new photocatalytic mechanism for this novel heterogeneous photocatalyst was proposed. Due to the close distance between Riboflavin molecules on the surface of the SiO2@RF photocatalyst, it prevented the dye from undergoing intersystem crossing, thus excluding the formation of the triplet excited state and therefore singlet oxygen. Consequently, the photo-stability of heterogenized riboflavin in the SiO2@RF photocatalyst was improved compared to its behavior in homogeneous media. Furthermore, the heterogeneous photocatalysis process for contaminant degradation occurred through electron transfer reactions from the singlet excited state. In the subsequent stage of research, the influence of the TiO2 layer thickness on the photocatalytic efficiency of supported photocatalysts SiO2@TiO2 was explored. The main objective was to optimize the efficiency of TiO2 in photocatalytic processes for contaminant degradation. Additionally, modifications were introduced in the sol-gel synthetic method for SiO2@TiO2 photocatalysts, intending to control both the rate of formation and the thickness of the TiO2 layer on the SiO2 spheres. After conducting a comprehensive characterization of these materials, the photocatalytic efficiency was evaluated in relation to the amount of TiO2 present in each SiO2@TiO2 photocatalyst. The results revealed a significant dependence of the photocatalytic activity on the thickness of the TiO2 layer, which correlated with the photoluminescence response of each sample. In this context, the synthesis and characterization of a SiO2@TiO2 photocatalyst, as well as glass wool coated with TiO2 (GW_TiO2), were carried out with the aim of eliminating an emerging contaminant of concern (CEC), sulfamethoxazole (SMX), in a simulated matrix of urban water under solar radiation. Furthermore, the incorporation of Fe3O4 nanocrystals into the shell of the SiO2@TiO2 photocatalyst was explored with the intention of acting as traps for photogenerated electrons, thereby minimizing their recombination while aiding in the recovery of the photocatalyst from the reaction medium. The synergy between TiO2 and Fe3O4 in the new SiO2@TiO2@Fe3O4 photocatalyst was evaluated in the removal of a model organic contaminant under UV-A radiation. The results showed that Fe3O4 attached to TiO2 can perform photo-Fenton reactions at neutral pH. Additionally, H2O2 and peroxymonosulfate (PMS) were evaluated as radical promoters, enhancing the photo-oxidative power of the SiO2@TiO2@Fe3O4 photocatalyst. Hence, PMS was more efficient than H2O2. Finally, a new macroscopic composite was designed and synthesized to improve the photocatalytic properties of existing ones. This new material consists of SiO2@TiO2 microparticles covalently bonded to glass wool, which in turn was coated with a layer of TiO2 crystals of optimized thickness according to previous chapter investigations (approximately 30 nm). The photocatalyst was implemented in a continuous flow photoreactr / Cabezuelo Gandía, O. (2024). Diseño y síntesis de nuevos fotocatalizadores para el tratamiento de aguas residuales [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/207353