Le principal objectif de la thèse est l'optimisation d'un procédé d'oxydation avancée par la mise en œuvre des outils de l'automatique moderne.Le procédé considéré concerne l'ozonation catalytique utilisé pour traiter les eaux résiduaires industrielles. L'optimisation de ce procédé consiste à contrôler l'abattement des polluants tout en minimisant le coût de fonctionnement du procédé. La mesure en ligne de la concentration en polluant est fournie par l'absorbance, grandeur corrélée à la DCO. Le procédé est alors considéré comme un système à une entrée, la puissance du générateur d'ozone, et deux sorties, l'ozone dans les évents et l'absorbance.L'identification du procédé a mené à l'estimation d'un modèle linéaire pour construire les lois de commande et d'un modèle non-linéaire, de type modèle de Wiener, pour tester les correcteurs en simulation avant les essais expérimentaux.Les trois commandes testées, la commande par modèle interne, la commande optimale et la commande H∞, permettent de rejeter des perturbations sur la concentration en polluant dans les effluents à traiter. Des analyses de stabilité du système bouclé, vis-à-vis de retards sur la commande, ont été menées.Les résultats expérimentaux obtenus ont permis de conclure sur les gains significatifs apportés par ces développements.La méthodologie développée pour cette application peut être étendue à d'autres procédés afin de faciliter le développement industriel des procédés d'oxydation avancée. / The main goal of the PhD thesis focuses on the optimization of an advanced oxidation process by implementing the modern control tools.The considered process is a lab-scale pilot of industrial wastewater treatment by catalytic ozonation. The optimization of this process is achieved by controlling the pollutant abatement while minimizing the high operating costs. The online measurement of the pollutant concentration is provided by the absorbance which is correlated with COD. Therefore, the process is considered as a system with one input, the ozone generator power, and two outputs, the ozone gas concentration at the top of the reactor and the absorbance.A linear model of the process was identified. It allowed calculating the control laws. And a nonlinear model, with a so-called Wiener model structure, was also identified to test the controllers in simulation before the experiments.The three control methods applied, the internal model control, the optimal control and the H∞ control, allow rejecting disturbance on the pollutant concentration of the effluent to be treated.The stability of closed-loop system with delayed control input was analyzed.The experimental results show the significant benefits provided by this closed-loop system.The methodology developed for this application can be extended to other processes to facilitate the industrial development of advanced oxidation processes.

La dépollution des sols contaminés par des hydrocarbures aromatiques polycycliques (HAPs) est un enjeu important de société, à la fois environnemental, économique et technologique, du fait du grand nombre de sites contaminés par ces composés toxiques et persistants. Les entreprises d’ingénierie de l’environnement utilisant des procédés conventionnels de bioremédiation font souvent face à des rendements trop faibles d’élimination des HAPs dans les sols historiquement contaminés. Il y a donc un besoin réel de développer des solutions innovantes.Dans cette étude, 6 sols historiquement contaminés par des huiles de goudron ont notamment été caractérisés par la présence de 42 à 86% des HAPs dans la fraction sableuse, adsorbés sur diverses particules de charbon/coke/bois ou intégrés à l’intérieur de particules d’huile de goudron résinifiées et altérées. Ainsi, en fonction du niveau de séquestration des HAPs, la séparation sélective de la fraction la plus contaminée ou l’utilisation de procédés de lavage de sol (LS) utilisant des surfactants apparaissent comme des alternatives prometteuses aux procédés de bioremédiation. Une attention particulière a ensuite été portée sur le procédé de LS utilisant des surfactants, qui est basé sur l’optimisation du transfert des HAPs du sol vers la solution de lavage. Ce procédé génère des solutions de LS contenant de grandes quantités de surfactants et de polluants. Celles-ci doivent être traitées dans le but d’éviter la contamination de l’environnement et d’améliorer le rapport coût-efficacité du procédé.L’oxydation anodique (OA) a été identifiée comme un procédé adéquat et prometteur pour le traitement de solutions de lavage de sol contenant des HAPs et du Tween® 80 comme agent d’extraction. La compréhension détaillée des mécanismes impliqués dans l’élimination des composés organiques présents dans les solutions de LS a permis de mettre en place deux stratégies de traitement différentes :• Tout d’abord, il a été mis en évidence que l’utilisation de l’OA à des courants faibles et pendant des temps de traitement longs (23 h) permet la dégradation sélective des polluants ciblés (les HAPs) et la réutilisation de la solution de LS pour des étapes supplémentaires de LS. La grande quantité de Tween® 80 ainsi économisée améliore fortement le rapport coût-efficacité et l’empreinte écologique des procédés de LS, en particulier lorsque la séquestration des polluants dans le sol requiert plusieurs étapes de LS et l’utilisation de fortes concentrations en surfactant.• En revanche, des rendements élevés d’élimination des composés organiques et la production de sous-produits plus biodégradables a été observée lors de l’utilisation de l’OA à faible intensité et pendant des temps de traitement court (3 h). Ainsi, des effets synergétiques ont été observés lors de la combinaison de l’OA avec un post-traitement biologique. D’importants rendements d’élimination avec des coûts opératoires optimisés peuvent être atteints. De plus, l’OA peut aussi être utilisée comme post-traitement pour l’élimination des composés faiblement biodégradables. Cette stratégie de traitement a pour but d’éviter toute contamination environnementale par les solutions de LS.Ces deux stratégies de traitement doivent être prises en considération pour une gestion optimale et appropriée des solutions de LS. Au vu des résultats prometteurs obtenus, les défis scientifiques reliés au changement d’échelle de ce procédé ont été discutés / Remediation of soil contaminated by polycyclic aromatic hydrocarbons (PAHs) is an important societal, environmental, economical and technological challenge, due to the high number of sites contaminated by these persistent and toxic compounds. Environmental engineering companies using conventional bioremediation processes often fails to reach sufficient PAH removal rates from historically contaminated soils. Therefore, there is a real need for the development of innovative solutions.In the present work, the characterization of 6 historically tar oil-contaminated soils showed that 42 to 86% of PAH are located in the sand fraction, either adsorbed on various coal/coke/wood particles or integrated in resinified and weathered tar oil particles. Thus, either selective separation of the most contaminated fraction or surfactant-enhanced soil washing (SW) appears to be promising alternatives to bioremediation, according to the level of sequestration of PAHs. Further investigations were performed on the surfactant-enhanced SW process, which is based on the transfer of PAHs from the soil-sorbed fraction to the washing solution. This process generates SW solutions containing a large amount of surfactant and pollutant. They have to be treated in order to avoid environmental contamination and ensure the cost-effectiveness of the whole process.Anodic oxidation (AO) was identified as a suitable and promising process for the treatment of SW solutions containing PAHs and Tween® 80 as extracting agent. The detailed understanding of mechanisms involved in the removal of organic compounds from SW solutions during AO allowed the implementation of two different treatment strategies:• First, it was emphasized that the use of AO at low current intensity during long treatment times (23 h) allows the selective degradation of target pollutants (PAHs) and the reuse of the SW solution for additional SW steps. Thus, the large amount of Tween® 80 saved strongly improves the cost-effectiveness and ecological footprint of SW processes, particularly when the high sequestration of pollutants requires several SW steps using high surfactant concentrations.• In contrast, high removal rates of organic compounds and production of more biodegradable by-products was observed during short treatment times (3 h) by AO at high current intensity. Thus, synergistic effects were observed for the combination of AO with a biological post-treatment. High removal rates with optimized operating costs can be achieved. Moreover, AO can also be used as a post-treatment (polishing step) for the removal of hardly-biodegradable compounds. This treatment strategy aims at avoiding environmental contamination by SW solutions.Both treatment strategies have to be considered for a suitable management of SW solutions. In view of promising results obtained, scientific challenges related to the scale-up of this process were discussed

Algal infestation in water bodies causes the release of soluble organic compounds that impact negatively on the taste and odour of the water. With increasing pollution in water bodies and increasing nutrient loading from agricultural activities, most water reservoirs in South Africa and around the world have become affected by this problem. In this study, an advanced oxidation process (AOP), namely, photocatalysis was evaluated for its potential to degrade aromatic compounds; and taste and odour causing bi-cyclic compounds originating from algae. Semiconductor photocatalysis is an environmentally friendly technology requiring no chemical inputs which is capable of completely mineralising organic pollutants to CO2 and H2O thereby eliminating production of unwanted by-products. Although processes involved in the photo-degradation have been reported for a wide range of pollutants, the degradative pathway in this process has not been fully established. In this study, compounds including phenol, 2-chlorophenol, 4-chlorophenol and nitrophenol were successfully eliminated from simulated wastewater. Degradation of geosmin at an environmentally significant initial concentration of 220 ng/L to levels below the lowest detectable concentration was achieved with an optimum catalyst concentration of 60 mg/L at a rate of 14.78 ng/L/min. Higher catalysts loading above 60 mg/L resulted in a decrease in degradation rates. An increase in initial geosmin concentration resulted in a decrease in rates. Ionic species commonly found in surface waters (HCO3 -, and SO4 2-) significantly reduced the efficiency of geosmin degradation. Degradation of geosmin produced acyclic intermediates from ring fission tentatively identified as 3,5-dimethylhex-1-ene, 2,4-dimethylpentan-3-one, 2-methylethylpropanoate and 2-heptanal. The results obtained indicate that the degradation of organic pollutants in aqueous solution is as a result of synergic action from hydroxyl radicals, positive holes and direct photolysis by UV radiation, though the predominant pathway of degradation is via hydroxyl radicals in solution. Major aromatic intermediates of phenol degradation include catechol, resorcinol and hydroquinone produced in the order catechol > resorcinol > hydroquinone. All three are produced within 2 minutes of photocatalytic reaction of phenol and remain in solution until all phenol is degraded in aerated systems. Production of resorcinol in non-aerated systems is transient, further supporting the hydroxyl radical dominant reaction pathway. / Thesis (PhD)--University of Pretoria, 2014. / gm2014 / Chemical Engineering / unrestricted

The occurrences of cyanotoxin and organic contaminants threaten drinking water sources and are a serious human health and environmental concern. The control of these problematic contaminants and the remediation of the associated contaminants are critical for ensuring safe drinking water to significant populations. Advanced oxidation processes (AOPs) have received considerable attention as a potential water treatment for various pollutants. In this dissertation, advanced oxidative degradation of four problematic water toxic contaminants (CYN, iopamidol, 4-methylcyclohexane methanol and propylene glycol phenyl ether) were studied to develop the fundamental understanding required to assess AOPs as a potential water treatment process. UV and visible light activated (VLA) TiO2 photocatalysis using nitrogen and fluorine-TiO2 (NF-TiO2), phosphorus and fluorine-TiO2 (PF-TiO2) and sulfur-TiO2 (S-TiO2) were employed for degradation of 6-hydroxymethyl uracil (6-HOMU), a model compound for the potent cyanotoxin cylindrospermopsin (CYN). NF-TiO2 exhibits the most photoactive, followed by marginally active PF-TiO2 and inactive S-TiO2 under visible light irradiation. Our results indicate that O2-• plays an important role in VLA TiO2 photocatalysis. Fe (VI), an environmentally friendly oxidant, was employed for the degradation of CYN and 6-HOMU over a range of pH (7 ~ 9.5). The second order rate constants for the reaction of Fe (VI) with CYN decrease from 38.83 ± 0.07 M-1s-1 at pH 7 to 5.02 ± 0.04 M-1s-1 at pH 9.5. Fe (VI) mediated reactions primarily occur via oxidation of the uracil ring in CYN. ELISA results demonstrate that Fe (VI) oxidation process leads to a significant decrease in the bioactivity of CYN as a function of treatment time. Fe (III)-oxalate/H2O2 process was employed for the remediation of iopamidol, a model for ICM, to determine the formation rates and steady concentrations of •OH and O2-• under UV and visible light irradiation. Reduction by CO2-• and oxidation by •OH contribute to the degradation pathways. Pulse and gamma radiolysis of 4-methylcyclohexane methanol (MCHM) and propylene glycol phenyl ether (PPh) were studied to determine the bimolecular rate constants and reaction pathways. •OH addition to ortho and para positions in PPh are the predominant reaction pathways; H-abstraction are the primary reaction mechanisms for ∙OH mediated oxidation of MCHM

The aim of this diploma thesis is the determination of selected organic pollutants with a focus on artificial sweeteners in waste water from wastewater treatment plant (WWTP) Modřice and the subsequent degradation of the thus obtained concentrations in model water using advanced oxidation processes (AOP). Two sweeteners were determined, namely sucralose and saccharin found in waste water. Synthetic sweeteners are not sufficiently cleaned in the WWTP and penetrate the environment. Effective processes for removing organic substances, including alternative sweeteners, are AOP processes. These processes are based on reactions of highly reactive hydroxyl radical (OH·), which is produced by many chemical reactions. Generally, they use ozone (O3) and hydrogen peroxide (H2O2). On sampling, wastewater samples were treated with Solid Phase Extraction (SPE) and then evaluated by HPLC/MS (High Performance Liquid Chromatography). In observing the degradation of selected sweeteners, three AOP methods were used: O3/UV, H2O2/UV and O3/H2O2. For each of these methods, the efficiency of degradation of sucralose and saccharin was investigated. From the evaluated data it was found that the most efficient AOP process for removing artificial sweeteners from water is the O3/H2O2 method.

This diploma thesis deals with the efficiency of removal of pharmaceuticals from drinking water by selected adsorption materials. The first part describes sources of pharmaceuticals in drinking water and possible ways of contaminating water by pharmaceuticals. Subsequently, the pharmaceuticals most commonly found in the environment - nonsteroidal anti-inflammatory drugs, antibiotics, psychiatric drugs and sex hormones - are described in more detail. Next, the thesis describes the processes used for removal of pharmaceuticals. These are activated carbon adsorption, membrane processes and advanced oxidation processes. The last chapter of the theoretical part of the thesis deals with water treatment plants, where the technologies for removing drugs are already in operation. In the practical part of this thesis an experiment was performed and evaluated, for a purpose of comparing the efficiency of selected sorption materials in the removal of diclofenac from water. Filtrasorb F100, Bayoxide E33 and GEH were used.

This diploma thesis focuses on possibilities of applications of UV radiation to remove pollutants from water. It summarizes sources of UV radiation and list their benefits and properties. The thesis characterizes so called advanced oxidation processes using UV light. Degradation pathways od pyridine and its derivatives especially halogenated pyridines are described. The photodegradability of pyridine and a rate of this reaction in model water is investigated in the experimental part. Also, the effect of concentration and dose of H2O2 is assessed. Gas chromatography was used to determinate concentrations of pyridine in samples.

<p>Cilj ovog rada bio je da se u laboratorijskim uslovima ispitaju efekti odabranih<br />unapredenih procesa oksidacije (Fenton proces, ozonizacija, TiO2-katalizovana ozonizacija,<br />perokson proces i TiO2-katalizovan perokson proces) i koagulacije na sadržaj i strukturu<br />prirodnih organskih materija u vodi, kao prekursora dezinfekcionih nusprodukata hlora.<br />Karaterizacija POM frakcionisanjem pre i nakon navedenih oksidacionih tretmana i<br />koagulacije izvr&scaron;ena je u cilju ispitivanja mehanizama oksidacije i uklanjanja POM, kao i<br />utvrdivanja promene reaktivnosti prekursorskog materijla DBP (trihalometana i halosircetnih<br />kiselina, kao najvi&scaron;e zastupljenih DBP, i haloacetonitrila, hlorpikrina i haloketona, kao<br />nedovoljno istraženih, visoko prioritetnih &bdquo;DBP u razvoju&ldquo;).<br />Analizom hemijskih karakteristika prirodnog matriksa utvrdeno je da voda sadrži<br />visoke koncentracije prirodnih organskih materija (DOC sirove iznosi 9,92&plusmn;0,87 mg/L) uz<br />dominaciju materija hidrofobnog karaktera (14% huminskih i 65% fulvinskih kiselina). U<br />slucaju sintetickog matriksa (sadržaj DOC 11,2&plusmn;0,37 mg/L) zastupljena je samo frakcija<br />huminske kiseline, te je iz tog razloga sinteticki matriks znatno hidrofobniji u odnosu na<br />prirodni. Veci stepen hidrofobnosti sintetickog matriksa u poredenju sa prirodnim matriksom,<br />rezultovao je i vecim sadržajem prekursora najzastupljenijih dezinfekcionih nusprodukata<br />hlora, THM i HAA. Vrednosti za PFTHM iznose 438&plusmn;88,2 &mu;g/L za prirodni matriks,<br />odnosno 3646&plusmn;41,3 &mu;g/L za sinteticki matriks, dok PFHAA prirodnog matriksa iznosi<br />339&plusmn;68,9 &mu;g/L, odnosno 559&plusmn;20,5 &mu;g/L za sinteticki matriks. Sadržaj HAN, CP i HK je<br />znatno niži u poredenju sa prekursorima THM i HAA. PFHAN iznosi 3,65 &mu;g/L za prirodni,<br />odn. 7,98 &mu;g/L za sinteticki matriks, dok prekursori CP nisu detektovani. Prekursori HK su<br />zastupljeni samo u strukturi POM prirodnog matriksa i PFHK iznosi 46,9&plusmn;5,08 &mu;g/L.<br />Hidrofoban materijal, kao dominantan u strukturi POM ispitivanih matriksa, je ujedno i<br />osnovni prekursorski materijal THM i HAA, dok su prekursori haloacetonitrila i haloketona u<br />navecoj meri zastupljeni u hidrofilnoj frakciji.<br />Ispitivanjem uticaja Fenton procesa na sadržaj POM, pri optimalnim reakcionim<br />uslovima (pH 5, reakciono vreme od 15 min. i brzina me&scaron;anja 30 o/min), postignuto je u<br />zavisnosti od primenjene doze Fe2+, molarnog odnosa Fe2+ i H2O2 i matriksa 80-95%<br />smanjenja saržaja DOC, 70-99% PFTHM, 37-92% PFHAA. Kao posledica uklanjanja POM<br />oksidaciojom i koagulacijom, zabeležene su blage fluktuacije u sadržaju prekursora HAN, CP<br />i HK.<br />Ispitivanjem uticaja ozonizacije u vodi pri razlicitim pH na sadržaj i strukturu POM<br />utvrdeno je da je ozonizacija u baznoj sredini efikasnija za uklanjanje POM u odnosu na<br />ozonizaciju u kiseloj sredini. Katalizovanje procesa ozonizacije primenom TiO2 u vodi<br />razlicitim pH unapreduje smanjenje sadržaja kako ukupnih organskih materija, tako i<br />specificnih prekursora DBP u poredenju sa ozonizacijom. Najefikasnije smanjenje sadržaja<br />POM postignuto je TiO2-O3 procesa u baznoj sredini primenom 3,0 mg O3/mg DOC i 1,0 mg<br />TiO2/L (30% DOC, 92-100% PFTHM, PFHAA, PFHAN i PFHK). TiO2-O3 proces pri svim<br />pH vrednostima produkuje manji sadržaj CP u odnosu na ozonizaciju. Veca efikasnost<br />primenjenih procesa u smanjenju sadržaja POM sintetickog matriksa u odnosu na prirodni<br />ukazuju da je frakcija huminske kiseline podložnija oksidacionom tretmanu u odnosu na<br />fulvinsku, kao dominantnu frakciju POM prirodnog matriksa. Kada je u pitanju mehanizam<br />oksidacije POM ispitivanih matriksa, primenom ozonizacije i TiO2-O3 procesa, pri svim pH<br />postignuta je potpuna oksidacija frakcije huminske kiseline do fulvinske kiseline i hidrofilnih<br />jedinjenja. U slucaju ozonizacije, sa povecanjem pH vrednosti sredine, usled povecane<br />produkcije hidroksil radikala iz ozona, povecao se i udeo odnosno sadržaj DOC u hidrofilnoj<br />frakciji ozonirane vode (86%-90%). Raspodela DOC nakon TiO2-O3 procesa pri svim pH<br />vrednostima je oko 70% i 50% u hidrofilnoj frakciji prirodnog i sintetickog matriksa, redom.<br />Frakcija koja se dominantno formira nakon navedenih oksidacionih tretmana je hidrofilna nekisela<br />frakcija. Frakcionisanjem POM nakon oksidacionih tretmana je utvrdeno da su<br />prekursori THM i HAA kako hidrofobne aromaticne strukture, tako i hidrofilna polarna<br />jedinjenja, dok je najreaktivniji prekursorski materijal HAN, CP i HK sadržan u hidrofilnoj<br />frakciji POM.<br />Uvodenjem H2O2 u proces ozonizacije (O3/H2O2 i iO2-O3/H2O2) u slabo baznoj<br />sredini (pH 7-7,5) postignut je jo&scaron; veci stepen oksidacije POM i povecanje udela hidrofilnih<br />struktura (oko 88%) ispitivanih matriksa u odnosu na ozonizaciju i iO2-O3 (oko 70%),<br />primenom 3,0 mg O3/mg DOC; O3:H2O2=1:1 i 1,0 mg iO2/L. Povecanje sadržaja prekursora<br />THM i HAA samo u slucaju prirodnog amtriksa posledica je povecanja reaktivnosti frakcije<br />fulvinske kiseline nakon O3/H2O2 i iO2-O3/H2O2 procesa, u kojoj su ujedno i prekursori HK<br />najzastupljeniji. Najveci sadržaj azotnih DBP (HAN i CP) sadrži hidrofilna frakcija POM.<br />Ispitivanjem kombinovanih procesa ozonizacije i TiO2-O3 i koagulacije utvrdeno je da<br />oksidacioni tretmani imaju pozitivne efekte u uklanjaju POM koagulacijom. Maksimalna<br />efikasnost smanjenja sadržaja DOC od 32% postignuto je primenom 3,0 mg O3/mg DOC i<br />200 mg FeCl3/L, dok su ne&scaron;to niže doze ozona pogodne za uklanjanje prekursora DBP (80-<br />89% PFTHM, PFHAA, PFHAN i PFHK, primenom 0,7-1,0 mg O3/mg DOC i 200 mg<br />FeCl3/L). Prekursori CP koji se formiraju ozonizacijom zaostaju u vodi nakon koagulacije.<br />Rezultati dobijeni tokom istraživanja ukazuju da se primenom razlicitih oksidacionih i<br />unapredenih oksidacionih procesa može smanjiti sadržaj POM i prekursora DBP do<br />odredenog stepena. Kao najefikasniji u uklanjaju kako ukupnih organskih materija, tako i<br />specificih prekursora DBP se pokazao Fenton proces. Kada su u pitanju unapredeni procesi<br />oksidacije zasnovani na primeni ozona, uvodenje katalizatora ili H2O2 kao oksidanta u proces<br />ozonizacije, kao i odabir optimalne pH vrednosti procesa može unaprediti oksidabilnost<br />organskih molekula. Pri tom, poznavanje mehanizama oksidacije POM iz razlicitih izvora<br />primenom ozona i/ili hidroksil radikala, kao i mehanizma uklanjanja POM koagulacijom<br />može se primeniti za odabir i optimizovanje odgovarajuceg procesa u tretmanu vode za pice,<br />a u zavisnosti od kvaliteta sirove vode.</p> / <p>The aim of this work was to examine under laboratory conditions the effects of<br />certain advanced oxidation processes (Fenton process, ozonation, TiO2-catalyzed ozonation,&nbsp;peroxone process and TiO2-catalyzed peroxone process) and coagulation on the content,&nbsp;structure and role of natural organic matter in water as the precursors of chlorine disinfection&nbsp;byproducts. The NOM was characterized by fractionation before and after these oxidation&nbsp;treatments and coagulation, in order to investigate NOM oxidation mechanisms and identify&nbsp;the changes in the reactivity of DBP precursor material (trihalomethanes and haloacetic acids,&nbsp;as the most abundant DBP, and haloacetonitriles, chloropicrin and haloketones, as underresearched,&nbsp;high priority &ldquo;emerging DBP&rdquo;).&nbsp;Through analysis of the chemical characteristics of the natural matrix, it was found&nbsp;that the water contains high concentrations of natural organic matter (raw water DOC was&nbsp;9.92 &plusmn; 0.87 mg/L) dominated by substances with a hydrophobic character (14% humic and&nbsp;65% fulvic acids). The synthetic matrix studied (DOC content of 11.2 &plusmn; 0.37 mg/L)&nbsp;contained only the humic acid fraction, and was therefore significantly more hydrophobic&nbsp;compared to the natural one. The greater degree of hydrophobicity in the synthetic matrix&nbsp;relative to the natural matrix resulted in a higher content of precursors of the most frequent&nbsp;chlorine disinfection byproducts, THM and HAA. The THMFP of the natural matrix was&nbsp;438&plusmn;88.2 mg/L, compared to 3646&plusmn;41.3 mg/L for the synthetic matrix, while the HAAFP of&nbsp;the natural matrix was 339&plusmn;68.9 mg/L, compared to 559&plusmn;20.5 mg/L for the synthetic matrix.&nbsp;The contents of HAN, CP, and HK precursors were much lower than the THM and HAA&nbsp;precursors. HANFP were 3.65 mg/L for natural, and 7.98 mg/L for the synthetic matrix,&nbsp;whilst CP precursors were not detected. HK precursors were present only in the structure of&nbsp;the natural NOM matrix, with a HKFP of 46.9&plusmn;5.08 mg/L. Hydrophobic material, as the&nbsp;dominant structure in the investigated NOM matrix, is the basic precursor material of THM&nbsp;and HAA, while the precursors of haloacetonitriles and haloketones are represented mostly in&nbsp;the hydrophilic fraction.<span style="font-size: 12px;">Whilst examining the influence of the Fenton process on the NOM content, under&nbsp;</span><span style="font-size: 12px;">optimal reaction conditions (pH 5, reaction time of 15 min and stirring speed of 30 rpm),&nbsp;</span><span style="font-size: 12px;">depending upon the applied dose of Fe2+, the molar ratio of Fe2+ and H2O2, and the matrix,&nbsp;</span><span style="font-size: 12px;">reductions in the DOC content of 80-95%, in the THMFP of 70-99%, and in the HAAFP of&nbsp;</span><span style="font-size: 12px;">37-92%, were achieved. As a result of removing NOM by oxidation and coagulation, mild&nbsp;</span><span style="font-size: 12px;">fluctuations in the contents of HAN, CP and HK precursors were recorded.&nbsp;</span><span style="font-size: 12px;">The investigation into the effects of ozonation at different pH levels on the content&nbsp;</span><span style="font-size: 12px;">and structure of NOM has shown that ozonation under alkaline conditions is more effective at&nbsp;</span><span style="font-size: 12px;">removing NOM than ozonation under acidic conditions. Catalyzing the ozonation process&nbsp;</span><span style="font-size: 12px;">using TiO2 in water with different pH promotes the reduction of both total organic matter and&nbsp;</span><span style="font-size: 12px;">specific DBP precursors in comparison with ozonation alone. The most effective NOM&nbsp;</span><span style="font-size: 12px;">reduction was achieved using the TiO2-O3 process in alkaline conditions using 3.0 mg O3/mg&nbsp;</span><span style="font-size: 12px;">DOC and 1.0 mg TiO2/L (30% DOC, 92-100% THMFP, HAAFP, HANFP and HKFP). The&nbsp;</span><span style="font-size: 12px;">TiO2-O3 process produces lower amounts of CP at all pH values, relative to ozonation. The&nbsp;</span><span style="font-size: 12px;">applied processes showed increased efficacy in reducing the NOM content of the synthetic&nbsp;</span><span style="font-size: 12px;">matrix compared with the natural matrix, which shows that the humic acids fraction is more&nbsp;</span><span style="font-size: 12px;">susceptible to oxidation treatments than the fulvic acids which are the dominant faction of the&nbsp;</span><span style="font-size: 12px;">natural NOM matrix. Regarding the NOM oxidation mechanism in the investigated matrices,&nbsp;</span><span style="font-size: 12px;">using ozonation and the TiO2-O3 process, complete oxidation of the humic acid fraction to&nbsp;</span><span style="font-size: 12px;">fulvic acids and hydrophilic compounds was achieved at all pH levels. In the case of&nbsp;</span><span style="font-size: 12px;">ozonation, increasing the pH in the matrix lead to an increase in hydroxyl radicals production&nbsp;</span><span style="font-size: 12px;">from ozone, and the proportion or content of DOC in the hydrophilic fraction of ozonated&nbsp;</span><span style="font-size: 12px;">water (86%-90%) increased. The distribution of DOC after the TiO2-O3 process at all pH&nbsp;</span><span style="font-size: 12px;">values was about 70% and 50% in the hydrophilic fraction of the natural and synthetic&nbsp;</span><span style="font-size: 12px;">matrices, respectively. The dominant fraction formed after the oxidation treatments was the&nbsp;</span><span style="font-size: 12px;">hydrophilic non-acid fraction. By NOM fractionation after the oxidation treatments, it was&nbsp;</span><span style="font-size: 12px;">shown that the THM and HAA precursors are hydrophobic aromatic structures and&nbsp;</span><span style="font-size: 12px;">hydrophilic polar compounds, whilst the most reactive precursor materials for HAN, CP and&nbsp;</span><span style="font-size: 12px;">HC are contained in the hydrophilic NOM fraction.&nbsp;</span><span style="font-size: 12px;">Introducing H2O2 into the ozonation process (O3/H2O2 and iO2-O3/H2O2) in weak&nbsp;</span><span style="font-size: 12px;">basic conditions (pH 7 to 7.5) enhances further the degree of NOM oxidation and increases&nbsp;</span><span style="font-size: 12px;">the proportion of hydrophilic structures (88%) in the examined matrices in comparison to&nbsp;</span><span style="font-size: 12px;">ozonation and iO2-O3 (about 70%), using 3.0 mg O3/mg DOC; O3:H2O2=1:1 and 1.0 mg&nbsp;</span><span style="font-size: 12px;">iO2/L. An increase in the THM and HAA precursor contents occurred in the case of the&nbsp;</span><span style="font-size: 12px;">natural matrix as a result of the increased reactivity of the fulvic acid fraction after the&nbsp;</span><span style="font-size: 12px;">O3/H2O2 and iO2-O3/H2O2 processes, and HK precursors were also present. The highest&nbsp;</span><span style="font-size: 12px;">content of nitrogen DBP (HAN and CP) was found in the hydrophilic NOM fraction.&nbsp;</span><span style="font-size: 12px;">By examination of the combined processes of ozonation, TiO2-O3 and coagulation, it was&nbsp;</span><span style="font-size: 12px;">shown that oxidative treatments have a positive effect on NOM removal by coagulation. A&nbsp;</span><span style="font-size: 12px;">maximum efficacy in reducing DOC by 32% was achieved with 3.0 mg O3/mg DOC and&nbsp;</span><span style="font-size: 12px;">200 mg FeCl3/L, whereas slightly lower ozone doses are suitable for the removal of DBP&nbsp;</span><span style="font-size: 12px;">precursors (80-89% THMFP, HAAFP, HANFP and HKFP, using 0.7-1.0 mg O3/mg DOC&nbsp;</span><span style="font-size: 12px;">and 200 mg FeCl3/L). CP precursors which are formed during ozonation remain in the water&nbsp;</span><span style="font-size: 12px;">after coagulation.&nbsp;</span><span style="font-size: 12px;">The results obtained during this investigation show that the application of different oxidation&nbsp;</span><span style="font-size: 12px;">and enhanced oxidation processes can reduce the contents of NOM and DBP precursors to&nbsp;</span><span style="font-size: 12px;">some degree. The most effective process at removing both total organic matter and specific&nbsp;</span><span style="font-size: 12px;">DBP precursors proved to be the Fenton process. With respect to enhanced oxidation&nbsp;</span><span style="font-size: 12px;">processes based upon the use of ozone, by introducing catalysts or H2O2 as an oxidant in the&nbsp;</span><span style="font-size: 12px;">ozonation process and by selecting the optimum pH for the process, the oxidizability of&nbsp;</span><span style="font-size: 12px;">organic molecules can be improved. In addition, knowledge of the NOM oxidation&nbsp;</span><span style="font-size: 12px;">mechanisms from different sources using ozone and / or hydroxyl radicals, as well as the&nbsp;</span><span style="font-size: 12px;">mechanism of NOM removal by coagulation, can be used to select and optimize the most&nbsp;</span><span style="font-size: 12px;">appropriate process in drinking water treatment, depending upon the quality of the raw water.</span></p>

The photocatalytic wastewater treatment facility presented in this thesis is a promising economic green technology that can degrade wastewater’s organic and ammonia pollutants, which produce environmentally sensitive products like CO2, H2O, Nitrates, etc. that can be captured and used in many biological and engineering ways. Previous advances used for this research was determining the importance of cleaning the photocatalytic nanocrystals, Fe-TiO2, as one of the revolutionary improvements that expose and maximizes the active surface of the photocatalytic nanocrystals to the pollutants enabling the strong oxidants produced by the absorption of a photon, excitation of an electron and positive hole to produce oxidants on the surface of the nanocrystals. The oxidants indiscriminately produce CO2 and H2O from living and non-living organic matter to obtain near ~100% clean water. This research focused on taking the next steps in the development of a wastewater cleaning facility tested in our laboratory. An important step involved coating Fe-TiO2 crystals onto flexible, strong, fiber-glass cloth using a sol-gel processing method. Success was found in this research by applying the coated fiberglass cloth into a photoreactor aimed to clean a large amount of water rather than the laboratory scale. / Graduate

[ES] En la presente tesis doctoral se ha estudiado la degradación de diferentes mezclas de contaminantes mediante el proceso de oxidación avanzada foto-Fenton solar, buscando alternativas que lo hagan más eficiente a un pH próximo a la neutralidad. Este proceso oxidativo se ha llevado a cabo a pH 5 mediante la adición de sustancias tipo húmicas (STH) extraídas de diferentes residuos orgánicos. Las STH se han extraído del residuo de la producción del aceite de oliva, del residuo del café y de lodos de depuradora deshidratados del reactor anaerobio de EDAR. Estas STH se han caracterizado por diferentes técnicas analíticas y se han adicionado al proceso foto-Fenton para comprobar su eficacia y eficiencia en el mismo. En el caso del uso de las STH provenientes del residuo de la oliva se han obtenido diferentes tiempos de fermentación y diferentes tamaños de fracciones. El estudio sobre STH preparadas sobre residuos con diferentes tiempos de fermentación, demuestra que los mejores resultados de degradación se obtienen con las muestras fermentada un mes, pero en cualquier caso no son significativas las diferencias, por lo que no sería necesario someter al residuo a ningún tiempo de fermentación previo a la extracción de las STH. En los ensayos con diferentes fracciones de STH, se determina que no es necesario el proceso de separación por membranas ya que las degradaciones obtenidas son muy similares, independientemente del uso de una u otra. Se ha probado su eficiencia en diferentes matrices de agua y se ha comprobado su capacidad para complejar el hierro manteniéndolo en disolución, obteniendo buenos resultados en todos los casos. Se han realizado ensayos de toxicidad sobre diferentes organismos para comprobar la detoxificación de las muestras tratadas. Los ensayos de toxicidad determinan que el compuesto clorfenvinfos es el más tóxico y que las muestras en presencia de las STH son más tóxicas antes de aplicar ningún tratamiento, debido a la capacidad surfactante de las mismas. El tratamiento de una mezcla de parabenos con STH de diferente procedencia, mejora los resultados de degradación de contaminantes cuando el proceso se aplica a pH próximo a la neutralidad. Se determina que las STH extraídas del café aplicadas con una cantidad extra de peróxido de hidrógeno (doble de la estequiométrica) proporcionan mejores resultados de degradación de contaminantes que las STH obtenidas de la oliva y del lodo de depuradora. De los ensayos toxicológicos realizados y del de disrupción endocrina, se concluye que el tratamiento durante un t30w de 30 minutos, pese a que consigue la degradación de los parabenos, no resulta suficiente para detoxificar las muestras, ya que las disoluciones finales presentan mayor toxicidad que las intermedias, por lo que se considera prolongar los tratamientos. Las STH extraídas del lodo de depuradora se han utilizado para el lavado de contaminantes cuando se quiere aumentar su concentración y tratar menores volumenes con mayor concentración. Se han acoplado procesos de membrana y procesos oxidativos. Se comprueba que las STH son capaces de atrapar el contaminante por la formación de micelas, impidiendo su paso por la membrana y facilitando el posterior tratamiento por proceso foto-Fenton del retentado obtenido. El análisis realizado por PARAFAC determina que existe una interacción entre las STH y el contaminante. Por otro lado, se ha comprobado la capacidad de generar especies reactivas por parte de las STH en presencia de Fe(II) y Fe(III) obteniéndose una velocidad de reacción más lenta, aunque más estable a lo largo del tiempo con el uso del Fe(III). Las STH extraídas de diferentes residuos han resultado eficientes para la degradación de contaminantes emergentes cuando se lleva el proceso foto-Fenton a pH 5 debido a su capacidad por un lado de complejar el hierro manteniéndolo en disolución y por otro a la capacidad de generar especies reactivas durante el proceso. / [CA] En la present tesi doctoral s'ha estudiat la degradació de diferents mescles de contaminants mitjançant el procés d'oxidació avançada foto-Fenton solar, buscant alternatives que ho facen més eficient a un pH pròxim a la neutralitat. Aquest procés oxidatiu s'ha dut a terme a pH 5 mitjançant l'addició de substàncies tipus húmiques (STH) extragudes de diferents tipus de residus orgànics. Les STH s'han extret del residu de la producció de l'oli d'oliva, del residu del café i de lodes de depuradora deshidratats del reactor anaerobi d'EDAR. S¿han caracteritzat per diferents tècniques analítiques i s'han addicionat al procés foto-Fenton per a comprovar la seua eficàcia i eficiència en el mateix. En el cas de les STH provinents del residu de l'oliva s'han obtingut diferents temps de fermentació i diferents tamanys de fraccions. En l'ús de diferents temps de fermentació millors resultats de degradació s'observen en el cas de la mostra fermentada un mes, però, en qualsevol cas no son significatives les diferències, per el que no és necesari sotmetre al residu a cap temps de fermentació abans de l'extracció. Respecte al assatjos en els diferents tamanys de fraccions es determina que no es necessari la separació per membranes, ja que, les degradacions obtenides son molt similars independentment de l'ús d'una fracció o altra. S'ha comprovat l'efectivitat en diferents matrius d'aigua i la capacitat de les mateixes per a complexar el ferro mantenint-lo en disolució, en bons resultats en tots els casos estudiats. Complementàriament s'han realitzat assajos de toxicitat sobre diferents organismes per tal de comprovar la detoxificació de les mostres tractades. Els assatjos de toxicitat determinen que el compost clorfenvinfos és el més tòxic i que les mostres en presència de les STH són més tòxiques, a causa de la capacitat surfactant d'aquestes. El tractament d'una mescla de parabens en STH de diferent procedència milloren els resultats de degradació de contaminants quan es porta el procés a pH pròxim a la neutralitat. Es determina que les STH extragudes del residu del café quan s'adiciona al procés una quantitat extra de peròxid de hidrògen (doble de la quantitat estequiomètrica) milloren els resultats de degradació de contaminnats comparant en les STH obtingudes de l'oliva i del lodes de depuradora. Dels assatjos toxicològics realitzats i del de disrupció endocrina, es conclou que el tractamnet en una duració de t30w 30 minuts no és suficient per a detoxificar les mostres encara que, la degradació dels parabens es consegueix. Per lo que es considera prolongar el temps de tractament. Les STH procedents del lodes de depuradora s'han utilitzat per al llavat de contaminants quan es troben a concentracions elevades. S'han acoplat processos de membrana i procesos oxidatius. Es comproba que les STH poden atrapar contaminnats per la formació de micel-les, bloquejant el pas del contaminant a través de la membrana i sent més fàcil el posterior tractament per foto-Fenton del retentat obtingut. L'anàlisi realitzat per PARAFAC determina que existeix una interacció entre les STH i el contaminant. D'altra banda, s'ha estudiat el mecanisme de reacció de les STH i la seua capacitat per a generar espècies reactives en presència de Fe(II) i Fe(III), obtinguen una reacció més lenta encara que més estable al llarg del temps en el Fe(III). Les STH extragudes de diferents residus han resultat eficients per a la degradció de contaminants emergents quan es porta el procés foto-Fenton a pH 5 a causa de la seua capacitat per un costat de complexar el ferro mantenint-lo en dissolució i d'altra banda per la seua capacitat de genera espècies reactives durant el procés. / [EN] In the present doctoral thesis, degradation of different pollutant mixtures using the advanced oxidation process called photo-Fenton has been studied, gaining further insight in how this process would take place at circumneutral pHs. Photo-Fenton was carried out at pH 5 by adding humic like substances (HLS) isolated from different organic residues. HLS have been isolated from olive mill wastes, coffee wastes and from wastewater treatment plant sludges. These HLS have been characterized by different analytical techniques and were added to photo-Fenton process to determine their efficacy and efficiency. In the use of HLS isolated from olive mill wastes, different fermentation times and different sizes were obtained. For the HLS from different fermentation times slightly better degradation results were obtained with one month fermentation time, however differences were insignificant to take it into account, and the conclusion of no need of residue fermentation was achieved. In the use of different sizes, the pollutant degradation kinetics were practically the same, concluding that the best option is to use a mixture of them all. Iron complexing ability were studied using different water matrixes with good results in all cases. Toxicity bioassays were carried out using different organisms to know which level of detoxification has achieved. Concluding that these HLS were able to act as iron complexing agents, and that chlorfenvinphos is the most toxic compound, and that water samples containing HLS seems to be more toxic at the end of the treatment time due to their surfactant capacity. A mixture of parabens was treated using different origin HLS at mild photo-Fenton process. HLS isolated from coffee were the most efficient when and extra amount of hydrogen peroxide were added (stoichiometric doble amount). The conclusion reached from toxicology bioassays and endocrine disruption is that the treatment time t30w 30 minutes is not enough to eliminated toxicity, even when the parabens removal was obtained. HLS from sludges were used for contaminant washing when pollutant concentration is high, fitting together membrane system and oxidative process. HLS formed micelles and can catch the pollutant inside, blocking the pass through the membrane. Thus, less volume is treated then by photo-Fenton making easier the process. PARAFAC analysis shows that exist an interaction between HLS and the pollutant. Finally, mechanism reaction between HLS with Fe(II) and Fe(III) and their capacity of generate reactive species were studies. Obtaining that in presence of Fe(III) the reaction is slower but the complex is most stable. HLS isolated from different residue types are useful when photo-Fenton process takes place at circumneutral conditions due to their ability to complex iron, remaining it in solution, and their ability to generate reactive species during the process. Is possible to eliminate emerging pollutants present in wastewaters by photo-Fenton process at mild pH conditions by adding these substances, adding value to the process, and promoting circular economy. / Quiero agradecer al Ministerio de Economía, Industria y Competitividad la concesión de la beca FPI asociada a un proyecto del Plan Nacional de I+D+i (BES- 2016-077962) “Tecnologías eficientes para la eliminación de contaminantes de preocupación emergente, contenidos en Directiva 2013/39/CE o de riesgo significativo según Directiva 2008/105/CE” dentro del que se engloba el trabajo realizado en la presente tesis doctoral. Así como a la Unión Europea por la financiación para la realización de las estancias internacionales. / García Negueroles, P. (2021). Empleo de sustancias tipo húmicas obtenidas a partir de diferentes residuos orgánicos en la eliminación de contaminantes emergentes [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/177595 / TESIS